Certainly in the U.K., the subject of "Chemistry" appears to be in free-fall decline, judging from the closure of various well-respected university departments which represent that discipline. I would like to call attention to an important figure in the history of Chemistry: William Allen Miller. Miller was Professor of chemistry at King's College, London, between 1845 and 1870, the year of his death. He began by studying medicine, at King's, but became a demonstrator in chemistry there in 1840. In 1841, he became assistant to Daniell (who was the inventor of the "Daniell Cell", and a founding father of modern electrochemistry), and in 1845 succeeded him as Professor of chemistry; in the same year he was elected a Fellow of the Royal Society (FRS). Miller was 28 years old at the time - a young man. He later served twice as President of "The Chemical Society" (1855-57; 1865-67) - the founding forerunner of "The Royal Society of Chemistry".
The range of Miller's scientific work is remarkable, although, in these days before "specialisation" happened, it was not uncommon for scientists to be just that, "scientists", and work in what would now be regarded as formally diverse fields within the separate disciplines of biology, medicine, chemistry, physics and agriculture ("environment" had not been coined yet). So, among his many activities, Miller was an accomplished mineralogical analyst, who brought the classical methods of analysis to bear upon various phosphates and other salts and minerals. He also served as a consultant for the Western Gaslight Company, to improve their facility at Vauxhall, Surrey, and also in undertaking "the analysis of particulate residues and other by-products of incomplete combustion in an industrial setting", (i.e. there were concerns about pollution, even then).
He was a pioneer in applying spectroscopic analysis in chemistry, of which there is one rather spectacular example. Miller was invited by his friend William Huggins, the astronomer, to collaborate with him in making measurements of spectral-lines from stars: he needed a comparison (fingerprint) with the spectra of authentic chemical elements, which Miller could provide. In August 1864, Huggins pointed his spectroscope at the planetary nebula NGC 6543 (HIV 37) in the Draco galaxy. He realised that he was looking at the spectrum of a luminous gas, and that its elements were in common with those present in several other nebulae, so providing proof of cosmological evolution. In 1866 Huggins was awarded the Royal Medal of the Royal Society, and in the following year he and Miller together received the Gold-Medal of the Royal Astronomical Society.
Miller also wrote a number of books, including: "Introduction to the Study of Inorganic Chemistry"; "On the Importance of Chemistry to Medicine"; "Practical Hints to the Medical Student"; "Elements of Agricultural Chemistry"; "Elements of Chemistry - theoretical and practical". Elements of Chemistry was published in three volumes: "Chemical Physics", "Inorganic Chemistry", "Organic Chemistry". I did buy the latter two books, 30 or so years-ago, at a total cost of 55 new pence (which was quite a lot out of my pocket-money at the time): they are worth considerably more than that now, being first-editions, but their real value is the wealth of information contained in them. Although "Elements" is described as theoretical and practical, there was, of course, no detailed theoretical framework for chemistry (e.g. electronic structure and chemical bonding) until the advent of quantum mechanics in the next century. However, atoms and molecules were recognised, and molecular formulae were determined by methods which are now referred to as "microanalysis". The results were good too, despite the fact that the equipment used was, by modern standards, comparatively primitive. [One point of note is that the combining-weight of carbon was taken as 6, not 12 as we now know it to be, and so it is necessary to divide the number of carbon atoms in a quoted formula by 2 to get the correct value].
An intuitive dimension may also be glimpsed in the creation of these works. Miller draws the distinction between "organic compounds" and "organized bodies", as he describes them: "Organic compounds possess a definite composition and often a perfectly defined crystalline structure. On the other hand, organized bodies such as muscular tissue and nervous structure never exhibit any tendency to crystalline structure and are so connected with each other as to form parts of a system, each of which is incomplete if severed from the remainder".
He considers further the nature of living organisms (I paraphrase him slightly): "A living body has the power of assimilating fresh particles, and of arranging them in the special form which characterises the class to which the individual organism belongs. This, physiological chemistry, is the most difficult branch of the science. Its difficulty depends not upon the obscurity which enshrouds the nature of life itself; for the essential nature of every description of force, and of the mysterious tie which exists between matter and force, has baffled the penetration of the profoundest philosophers, and belongs to an order of truths to which the human intellect probably may not be permitted in this sphere of existence to attain".
Since then, molecular biology has emerged, and so our knowledge is such that some of the processes of life are perhaps less mysterious, but Miller's reflections remain profound. But what has happened to the science of Chemistry since the 1850's? Clearly, the subject in all its aspects has exploded (no pun intended in the popular view of chemistry, as "stinks and bangs"!); mainly through advances in analytical technology that in the 1850's could not have been dreamed of. It has underpinned the development of the industrialised nations of the world. Chemistry still provides a highly significant contribution to the U.K. national economy; though probably less so than banking and the financial sector generally, which is what fuels the "service-sector" that underpins modern society.
But if chemistry is so important, then the subject should be in a healthy state: well-supported for the research and teaching of it, and a popular choice for students enrolling at our universities? Whereas, in fact, chemistry is under considerable threat. It seems poignant that King's College, where Miller was professor of chemistry, looks set to close its chemistry department, with Queen Mary (College) now following suite, on top of Exeter and Swansea (I almost applied for a chair in the latter institution, but decided against it - wisely as it transpired!); and these are merely the latest on quite a long list of closed chemistry departments in the U.K. The most common cause of science departments being closed is a lack of student numbers; and chemistry (along with physics and maths) has lost popularity.
Moreover, the human-race is also under considerable threat, as our environment seems poised against us: either in retaliation for our abuses of it, or simply by way of the patterns of Nature. We are threatened generally by pollution, and more specifically by greenhouse-gases which may contribute to global-warming, but we require technical strategies with which to calm these assailants. Only scientifically qualified people can inform the appropriate bodies (e.g. governments and industries) so that the correct decisions can be made, as opposed to badly-considered, emotional reactions to problems, that might do more harm than good. We therefore need more students studying chemistry in the first instance, then taking it up as a profession - but how can this be achieved?
While there are laudable campaigns, e.g. by The Royal Society of Chemistry, to promote the subject at the school-level and among younger people generally, the most effective means would probably be financial. Perhaps the government should cover (some-of) the top-up fee for well-qualified candidates to enroll on chemistry courses, or provide some other financial incentive, such as a prize of £5-10K, say, for staying-the-course and achieving a "good-honours-degree" in chemistry.
Alternatively, those who finally employ chemistry (and other science) graduates, mainly government departments and industry, could simply pay them better. I note finally that my alma mater, the School of Molecular Sciences at the University of Sussex, which in its hayday could proclaim 2 Nobel Laureates and 7 Fellows of the Royal Society, and which awarded me a Higher Doctorate (D.Sc) in 2003, has just announced the closure of its Chemistry Department. Ye Gods! Is nowhere safe among the cash-only British University system?!
Adapted and updated from an address given by Professor Chris Rhodes, at the Holiday Inn, Liverpool, 27-11-03, following the award of prizes to chemistry students in the North West, at a ceremony hosted by the Royal Society of Chemistry.
Thursday, March 30, 2006
Saturday, March 25, 2006
Lakes Under Siege: Lake Chad and the Aral Sea.
Once the fourth largest lake in Africa and the sixth largest body of water in the world, Lake Chad is disappearing fast. In 1963 the surface area of the lake was 25,000 square kilometers (km*2), but today it barely accounts for 1,350 km*2. The lake is shared by Camaroon, Chad, Niger and Nigeria; countries which along with Central African Republic (CASR) constitute the Lake Chad Basin Commission (LCBC), which in French is called Commission du Basin du Lac Tchad (CBLT). The basin extends to almost one million km*2 (about four times the area of mainland U.K.), and is home to around 20 million people. The lake is very shallow, of the order of only 5 - 8 meters deep, and its waters provide a living for crop farmers, herders, fishermen and entire local communities. Now, in the wake of the receding waters, many find their livelihoods under threat.The lake is fed by the Chari and Longone rivers, and is land-locked with no outlet to the oceans. Since it is on the edge of the Sahara desert, high temperatures ensure that the evaporation rate of water from the lake is also high, at around 2,000 mm per year. This may be compared with an annual rainfall of 1,500 mm in the south but just 100 mm in the north.
The level of the lake has varied over time, according to the prevailing global temperature and regional rainfall. At one point in its history Lake Chad was sufficiently vast that modern historians refer to it as "Mega-Chad", while at other times it has all but disappeared. These changes over millennia can all be ascribed to natural phenomena, with human influence playing at most a bit part. This is no longer the case, and in recent decades, human activities in the lake's watershed mean that ever increasing volumes of water must be withdrawn in order to build dams, for irrigation and other purposes. The pressure of population is compounded by climate change, with the apparently inexorable advance of the Sahara.
The recent drying-up of lake Chad appears to have started in the 1960's, and then continued unabated for two decades. Its principal cause was a dramatic lack of rainfall for more than 10 years combined with record high temperatures. During the disasterous Sahelian drought of 1968 - 1973, the lake decreased in surface area by 20%. By the 1980's and 1990's, water flow from the rivers had been deliberately diverted from the lake, increasingly for use in irrigation schemes. It is estimated that only about two-thirds of streamflow from the river Chari now reaches Lake Chad. The extent of streamflow diversion remained at a comparatively low volume until the late 1970's, when the Chad basin countries started to rapidly increase the density of their cash crop (e.g. food and fibre) production. According to UNEP GRID, "...between 1953 and 1979, irrigation had only a modest impact on the Lake Chad ecosystem. Between 1983 and 1994, however, irrigation water use increased four-fold. About 50% of the decrease in the lake's size since the 1960's is attributed to human water use, with the remainder attributed to shifting climate patterns."
Clearly, the lake's fishermen have been greatly and adversely affected by its shrinkage, while some farmers have benefited from the exposure of the seabed, which provides a moist and fertile soil for growing crops and grazing animals on. The sustainable future of Lake Chad is not assured, as population pressures for water, land and food increase. There are serious environmental problems associated with Lake Chad, which include soil salinisation, invasion of unwanted plant varieties, increasing demands for irrigation, loss of fisheries, all of which are accompanied by an increase in the poverty of the Chad basin nations. Governments dependent on Lake Chad water have appealed for international support to help replenish the lake. The Science-in-Africa web site reported that the project "(Lake Chad Replenishment Project"), would entail damming the Oubangui River at Palambo in the Central African Republic (CAR) and channeling some of its water through a navigable canal to Lake Chad. It is a large-scale project which requires heavy resources." Thus spake Niger's Minister of environmental and Hydraulic Affairs, Adamou Namata. It is reassuring to note that there is a will among some of the relevant governments of the region to save the lake.
Though apparently unrelated, being thousands of miles distant, it is the Aral Sea whose history points to a potential and disarming future for Lake Chad. Forty years ago, the Aral was the fourth largest inland body of water in the world. Due to an unbridled exploitation of water resources, today the sea - really a land-locked lake - faces extinction. The Aral Sea is shared by Uzbekistan and Kazakhstan. There are two main rivers in Central Asia, the Amudarya and Syrdarya, which provide the main arteries for water flow into the Aral. Both Uzbekistan and Kazakhstan lie downstream of both rivers, while upstream are a number of countries, including Tajikistan, Kyrgystan and Afghanistan. Turkmenistan uses a major canal to withdraw a disproportionate quantity of the Amudarya's water before it reaches Uzbekistan's irrigation canals and farmlands.
Human activities in the region have increased markedly since the 1960's, and accordingly the pressure on streamflow diversions has intensified, to the extent that since the late 1970's, in many years, the flow of either one or both of the rivers has not made it as far as the Aral Sea. In consequence, the water level in the Aral has fallen steadily, and has dropped to a total of about 20 meters on average since 1960. Indeed, much of the "sea" is now dry land, with the hulls of beached ships resting on it. Since the Aral Sea was also heavily polluted from industrial processes, e.g. cotton production, a mainstay of Uzbekistan's economy, the loss of its water has uncovered a multitude of environmental sins, where dust from the contaminated seabed now is blown around indiscriminately by the Central Asian winds. Kazakhstan's leaders made a decision to save the northern part of the Aral, called the "Little Aral". The larger Aral to the south has since been divided into eastern and western provinces, on the edge of complete dessication and dust. The lucrative fishing industry that once supported 60,000 people has disappeared, mainly due to the loss of fish caused by the fall in both the quantity and quality of the Aral waters.
There is probably nothing that can be done to save the Aral Sea - its conditions are past the point of no-return. In contrast, Lake Chad might yet be saved, but only if there is sufficient political will to do so.
The level of the lake has varied over time, according to the prevailing global temperature and regional rainfall. At one point in its history Lake Chad was sufficiently vast that modern historians refer to it as "Mega-Chad", while at other times it has all but disappeared. These changes over millennia can all be ascribed to natural phenomena, with human influence playing at most a bit part. This is no longer the case, and in recent decades, human activities in the lake's watershed mean that ever increasing volumes of water must be withdrawn in order to build dams, for irrigation and other purposes. The pressure of population is compounded by climate change, with the apparently inexorable advance of the Sahara.
The recent drying-up of lake Chad appears to have started in the 1960's, and then continued unabated for two decades. Its principal cause was a dramatic lack of rainfall for more than 10 years combined with record high temperatures. During the disasterous Sahelian drought of 1968 - 1973, the lake decreased in surface area by 20%. By the 1980's and 1990's, water flow from the rivers had been deliberately diverted from the lake, increasingly for use in irrigation schemes. It is estimated that only about two-thirds of streamflow from the river Chari now reaches Lake Chad. The extent of streamflow diversion remained at a comparatively low volume until the late 1970's, when the Chad basin countries started to rapidly increase the density of their cash crop (e.g. food and fibre) production. According to UNEP GRID, "...between 1953 and 1979, irrigation had only a modest impact on the Lake Chad ecosystem. Between 1983 and 1994, however, irrigation water use increased four-fold. About 50% of the decrease in the lake's size since the 1960's is attributed to human water use, with the remainder attributed to shifting climate patterns."
Clearly, the lake's fishermen have been greatly and adversely affected by its shrinkage, while some farmers have benefited from the exposure of the seabed, which provides a moist and fertile soil for growing crops and grazing animals on. The sustainable future of Lake Chad is not assured, as population pressures for water, land and food increase. There are serious environmental problems associated with Lake Chad, which include soil salinisation, invasion of unwanted plant varieties, increasing demands for irrigation, loss of fisheries, all of which are accompanied by an increase in the poverty of the Chad basin nations. Governments dependent on Lake Chad water have appealed for international support to help replenish the lake. The Science-in-Africa web site reported that the project "(Lake Chad Replenishment Project"), would entail damming the Oubangui River at Palambo in the Central African Republic (CAR) and channeling some of its water through a navigable canal to Lake Chad. It is a large-scale project which requires heavy resources." Thus spake Niger's Minister of environmental and Hydraulic Affairs, Adamou Namata. It is reassuring to note that there is a will among some of the relevant governments of the region to save the lake.
Though apparently unrelated, being thousands of miles distant, it is the Aral Sea whose history points to a potential and disarming future for Lake Chad. Forty years ago, the Aral was the fourth largest inland body of water in the world. Due to an unbridled exploitation of water resources, today the sea - really a land-locked lake - faces extinction. The Aral Sea is shared by Uzbekistan and Kazakhstan. There are two main rivers in Central Asia, the Amudarya and Syrdarya, which provide the main arteries for water flow into the Aral. Both Uzbekistan and Kazakhstan lie downstream of both rivers, while upstream are a number of countries, including Tajikistan, Kyrgystan and Afghanistan. Turkmenistan uses a major canal to withdraw a disproportionate quantity of the Amudarya's water before it reaches Uzbekistan's irrigation canals and farmlands.
Human activities in the region have increased markedly since the 1960's, and accordingly the pressure on streamflow diversions has intensified, to the extent that since the late 1970's, in many years, the flow of either one or both of the rivers has not made it as far as the Aral Sea. In consequence, the water level in the Aral has fallen steadily, and has dropped to a total of about 20 meters on average since 1960. Indeed, much of the "sea" is now dry land, with the hulls of beached ships resting on it. Since the Aral Sea was also heavily polluted from industrial processes, e.g. cotton production, a mainstay of Uzbekistan's economy, the loss of its water has uncovered a multitude of environmental sins, where dust from the contaminated seabed now is blown around indiscriminately by the Central Asian winds. Kazakhstan's leaders made a decision to save the northern part of the Aral, called the "Little Aral". The larger Aral to the south has since been divided into eastern and western provinces, on the edge of complete dessication and dust. The lucrative fishing industry that once supported 60,000 people has disappeared, mainly due to the loss of fish caused by the fall in both the quantity and quality of the Aral waters.
There is probably nothing that can be done to save the Aral Sea - its conditions are past the point of no-return. In contrast, Lake Chad might yet be saved, but only if there is sufficient political will to do so.
Thursday, March 23, 2006
Peak Oil - are we all doomed?
The answer to the question depends on our interpretation of it. If it means, "are our energy intensive, gas guzzling societies doomed?" then the answer is, "yes, they are." If the sense is deemed broader, to ask, "do the majority of us have to die-off," in an apocalyptically nasty scenario of post "Peak Oil" (see my earlier posting "Die Off"), then the answer is, "not necessarily, but it depends on which course we chart." If we go in the right direction we will arrive in a safe land, but to find it, we might do worse than to take a guide from Cuba with us. Cuba used to receive an annual largesse worth billions of dollars from the U.S.S.R., which included plentiful agricultural supplies, fuel, pesticides, fertilisers, animal feed and seeds. In the wake of the break-up of the U.S.S.R. and eastern-bloc countries, the economic consequences were such that there was nothing left over for Cuba. Having found themselves thrown upon their own resources, the Cuban response was a focus on sustainable living, and now there are thousands of city gardens flourishing, planted on wastelands, rooftops and most tellingly, former carparks, made available by the demise in transportation use.
Cuba is thought to have over 2700 gardens which employ a total of 22,000 workers and produce more than two dozen different kinds of vegetables and herbs, which are sold to local consumers directly at anywhere down to about half the market price. Additionally,over 4000 larger and more intensive gardens operate, mostly on the outskirts of towns and cities. Due to the lack of chemical pesticides and fertilisers, all of this gardening is of necessity mainly organic. By supplying the produce at source for a local community there is no need for transportation. Many state enterprises, schools and hospitals grow some of their own food and farm livestock too. Some local communities produce up to 30% of their food, and over 500,000 tonnes of produce was made available for residents of Havana last year. There are health issues too, and it is thought that with enhanced yields from the gardens, most of the country should be able to meet the recommended allowance of 300 grams of vegetables per person per day. The more highly populous cities of Havana and Santiago de Cuba will not be able to produce this level from city gardens alone, however.
Cuba's economic crisis, protracted for more than a decade, with food shortages and a severe curtailment of transportation by lack of fuel, forced the nation to focus on less energy and transport intensive forms of production, distribution and marketing of foodstuffs, by operating on a local level. To be sure, Cuba is trying to improve its lot beyond the level of local food production, mainly through tourism and exploiting its mineral wealth (both energy intensive activities), but nonetheless, their basic lesson might provide the means for our survival, rather than a "Die Off" scenario, where ultimately everybody loses.
If we are at the point of "Peak Oil" (see my previous posting) and we can expect a steady rise in costs and an increasingly insecure supply of transportation fuel, adopting the Cuban model of urban agriculture, where relatively small communities of perhaps 10,000 - 20,000 people are provided for by local farms may be our solution. It would be better to pursue this line by choice and soon, rather than hide our heads in the sand until the problem is so hungry it can no longer be ignored.
Cuba is thought to have over 2700 gardens which employ a total of 22,000 workers and produce more than two dozen different kinds of vegetables and herbs, which are sold to local consumers directly at anywhere down to about half the market price. Additionally,over 4000 larger and more intensive gardens operate, mostly on the outskirts of towns and cities. Due to the lack of chemical pesticides and fertilisers, all of this gardening is of necessity mainly organic. By supplying the produce at source for a local community there is no need for transportation. Many state enterprises, schools and hospitals grow some of their own food and farm livestock too. Some local communities produce up to 30% of their food, and over 500,000 tonnes of produce was made available for residents of Havana last year. There are health issues too, and it is thought that with enhanced yields from the gardens, most of the country should be able to meet the recommended allowance of 300 grams of vegetables per person per day. The more highly populous cities of Havana and Santiago de Cuba will not be able to produce this level from city gardens alone, however.
Cuba's economic crisis, protracted for more than a decade, with food shortages and a severe curtailment of transportation by lack of fuel, forced the nation to focus on less energy and transport intensive forms of production, distribution and marketing of foodstuffs, by operating on a local level. To be sure, Cuba is trying to improve its lot beyond the level of local food production, mainly through tourism and exploiting its mineral wealth (both energy intensive activities), but nonetheless, their basic lesson might provide the means for our survival, rather than a "Die Off" scenario, where ultimately everybody loses.
If we are at the point of "Peak Oil" (see my previous posting) and we can expect a steady rise in costs and an increasingly insecure supply of transportation fuel, adopting the Cuban model of urban agriculture, where relatively small communities of perhaps 10,000 - 20,000 people are provided for by local farms may be our solution. It would be better to pursue this line by choice and soon, rather than hide our heads in the sand until the problem is so hungry it can no longer be ignored.
Monday, March 20, 2006
Chernobyl (26th April 1986).
Although the event has received little press attention so far, the days are inching toward the 20th anniversary of the disaster at the Chernobyl nuclear power plant, which occurred on the 26th of April, 1986. Since the result was widespread radioactive contamination, Chernobyl was not a single event, but is an ongoing process. I remember the initial event well, and its aftermath, since I was working in Russia at the time. There was, as I recall, very little information made available within the U.S.S.R., and my Russian colleagues learned most about what had happened from their colleagues in the West. I have mentioned "Chernobyl" to a few of my friends and acquaintances recently, and from this small survey it seems that no-one under the age of about forty is aware of even the name of the place, let alone what happened there.
It was thought initially that there had been a release of radioactive material from the Forsmark nuclear power station in Sweden. The story at the time was that one man, having spent the weekend out hiking, had set-off the radiation monitors on his way "into" work, rather than on the way out of the plant. Once it was established that there was no leak at Forsmark, a search was inaugurated for the real source, which led to the first suggestion of a major nuclear incident in the western Soviet Union. As I recall, this was immediately denied, then played-down, and finally the extent of the problem was admitted, of a magnitude which nobody before or since has had to deal with. Let's hope it stays that way.
The upshot was an international cooperation involving health specialists, physicists, nuclear engineers, radiation biologists and many other kinds of scientists from all over the world, working together toward the common goal of stabilising the reactor and decontaminating land, animals and humans, to minimise further calamity. These efforts continue.
Contoversy remains as to the precise cause of the events at Chernobyl, but there appears to have been an inopportune convergence of circumstances. There is some speculation that the design of the RBMK-1000 reactor is inherently unsafe, in particular the control rods. Dangerous operating procedures were blamed too, in that many of the reactor safety systems had been turned off in order to conduct an experiment during which all but seven of the total 211 control rods were removed from the reactor. On the night of April the 25th, the unit 4 reactor was due to be shut down for routine maintenance, and the decision was taken to test whether the reactor turbine generator could provide enough electricity to run the reactor's safety systems in the event of a loss in external electric power. Ironically in the interests of safety, the power output was reduced to an intended level of 700 MW from the normal level of 3.2 GW (thermal power = 1 GW electrical power); however, it actually fell to just 30 MW. It was decided to power-up the reactor by pulling out the control rods, but because the water flow ran much higher than normal, and water absorbs neutrons hence reducing the reactor power, the control rods were removed manually, thus rendering the reactor in a very unstable condition. The power of the reactor suddenly increased, particularly as bubbles of steam formed in the primary coolant and rose further, whereupon a "scram" was ordered, meaning that all the control rods are inserted, which should shut-down the reactor.
However, due to the hollow tips of the rods and the temporary displacement of coolant, this actually caused the power to rise further still and the consequent high temperature distorted the control rod channels, with the result that the rods became stuck on the way down, and were thus unable to slow down the reactor. However, it was recently pointed put to me by an expert on nuclear power who has worked at Sellafield for many years that "the Chernobyl accident was not due to sticking control rods: once their full withdrawal (in defiance of standing rules and after deliberate disablement of safety systems) had succeeded in starting a rise in power level, inherent positive feedback effects rendered it unstoppable with a rapid rise to an estimated hundred times nominal maximum." The reactor power jumped to about ten times its rated output, the fuel rods began to melt and the water in the primary coolant circuit flashed to steam causing a "steam explosion" of sufficient force to rupture the cooling pipes, blow the 1000 tonne concrete containment lid off the top of the reactor, and blast a hole through the roof of the building. The person who pressed the "scram" button died of radiation poisoning two weeks after the incident.
Remarkably, the Chernobyl disaster could have been far worse, and tremendous efforts were made to "bury" the reactor by dropping thousands of tonnes of sand, lead, boric acid and other materials onto it from helicopters. Counter-productively, the effect of these materials was like lining the walls of a furnace with firebrick and increased the temperature of the molten fuel which was already melting its way through the reactor floor. Water that had been pumped into the building in a vain effort to extinguish the fire from the burning graphite moderator began to collect beneath the reactor and without the self sacrifice of two men ("liquidators") sent in wearing only divers' "wet suits" to release the valve and vent the radioactive water from the building, a thermal explosion would have ensued when the molten fuel contacted it, rendering an area of land around the plant occupying hundreds of thousands of square kilometers uninhabitable for hundreds of years. There are various estimated figures, but undoubtedly many lives were saved by these two men, who gave their own in so doing.
It is estimated (http://en.wikipedia.org/wiki/chernobyl_accident) that the unit 4 reactor contained around 180-190 tonnes of uranium oxide fuel and its fission products. With the reactor core exposed, oxygen came into contact with the very hot fuel and graphite moderator, causing the latter to catch fire. This resulted in a plume of radioactive smoke being borne upwards into the atmosphere, from where it was transported by weather currents over much of the western U.S.S.R. In Bulgaria, children were fed biscuits baked with zeolites in them - see my earlier listing "Zeolites - the stones that boil" - in an effort to remove any radioactive caesium and strontium they may have ingested. The adults were advised to drink a bottle of red-wine every day, in the belief or hope that the antioxidants in it would protect them against the effects of radiation. The fallout was further carried over western Europe, and as far as the western United States. 375 farms remain contaminated in the U.K. which hold 200,000 sheep - the sheep need to be moved to uncontaminated ground and grazed there for a few weeks before they are fit for market, and then only following an inspection by an appropriately accredited vet.
The human costs are immense. About 50 people died in the immediate stages; 28 from acute radiation exposure. Some children living in heavily contaminated areas received very high radiation doses of up to 50 Grays (Gy) from the absorption of iodine-131, a radioactive isotope with a half life of 8 days (far shorter than the biological half life for residence in the thyroid of 120 days). This, they ingested from locally produced milk which was heavily contaminated, and nine of them died from thyroid cancer. In total it is estimated that another 3,940 people are likely to die from cancer as a consequence of radiation exposure from Chernobyl. Over 300,000 people were rapidly displaced to safer areas after the disaster, 50,000 of them from the town of Pripyat where the nuclear power plant actually is (it lies 11 miles to the north west of the city of Chernobyl). In the intervening time many, mostly the old, have returned to their former homes.
The political impact of the Chernobyl disaster has been highly significant. It has been said that the event itself and the complications of dealing with it which were compounded by the prevailing Soviet secrecy of the time, helped to bring about the dissolution of the Soviet Union. It's initial influence was to turn nation populations and their leaders more steadfastly away from nuclear power. Ramping up the arms-race too, would have been unthinkable. Time and circumstances have moved on since then and the U.K. looks set to promulgate its nuclear capability, although the government is receiving somewhat conflicting advice. It's Chief Scientific Advisor advocates nuclear power on grounds of its low carbon emissions while a number of highly credible objections have been raised in a recent report by the Sustainable Development Committee. Assuming we do "go nuclear" I recall reading a while back that the government had planned an extra £10 billion for the purpose, and I see that £2 billion is planned to overhaul the Atomic Weapons Establishment at Aldermaston (http://www.awe.co.uk). The U.S. and Russia too, are each refurbishing their own nuclear defenses, though within guidelines agreed between them.
20 years on, I see that the nuclear issue, while lying dormant until recently, never entirely went away.
It was thought initially that there had been a release of radioactive material from the Forsmark nuclear power station in Sweden. The story at the time was that one man, having spent the weekend out hiking, had set-off the radiation monitors on his way "into" work, rather than on the way out of the plant. Once it was established that there was no leak at Forsmark, a search was inaugurated for the real source, which led to the first suggestion of a major nuclear incident in the western Soviet Union. As I recall, this was immediately denied, then played-down, and finally the extent of the problem was admitted, of a magnitude which nobody before or since has had to deal with. Let's hope it stays that way.
The upshot was an international cooperation involving health specialists, physicists, nuclear engineers, radiation biologists and many other kinds of scientists from all over the world, working together toward the common goal of stabilising the reactor and decontaminating land, animals and humans, to minimise further calamity. These efforts continue.
Contoversy remains as to the precise cause of the events at Chernobyl, but there appears to have been an inopportune convergence of circumstances. There is some speculation that the design of the RBMK-1000 reactor is inherently unsafe, in particular the control rods. Dangerous operating procedures were blamed too, in that many of the reactor safety systems had been turned off in order to conduct an experiment during which all but seven of the total 211 control rods were removed from the reactor. On the night of April the 25th, the unit 4 reactor was due to be shut down for routine maintenance, and the decision was taken to test whether the reactor turbine generator could provide enough electricity to run the reactor's safety systems in the event of a loss in external electric power. Ironically in the interests of safety, the power output was reduced to an intended level of 700 MW from the normal level of 3.2 GW (thermal power = 1 GW electrical power); however, it actually fell to just 30 MW. It was decided to power-up the reactor by pulling out the control rods, but because the water flow ran much higher than normal, and water absorbs neutrons hence reducing the reactor power, the control rods were removed manually, thus rendering the reactor in a very unstable condition. The power of the reactor suddenly increased, particularly as bubbles of steam formed in the primary coolant and rose further, whereupon a "scram" was ordered, meaning that all the control rods are inserted, which should shut-down the reactor.
However, due to the hollow tips of the rods and the temporary displacement of coolant, this actually caused the power to rise further still and the consequent high temperature distorted the control rod channels, with the result that the rods became stuck on the way down, and were thus unable to slow down the reactor. However, it was recently pointed put to me by an expert on nuclear power who has worked at Sellafield for many years that "the Chernobyl accident was not due to sticking control rods: once their full withdrawal (in defiance of standing rules and after deliberate disablement of safety systems) had succeeded in starting a rise in power level, inherent positive feedback effects rendered it unstoppable with a rapid rise to an estimated hundred times nominal maximum." The reactor power jumped to about ten times its rated output, the fuel rods began to melt and the water in the primary coolant circuit flashed to steam causing a "steam explosion" of sufficient force to rupture the cooling pipes, blow the 1000 tonne concrete containment lid off the top of the reactor, and blast a hole through the roof of the building. The person who pressed the "scram" button died of radiation poisoning two weeks after the incident.
Remarkably, the Chernobyl disaster could have been far worse, and tremendous efforts were made to "bury" the reactor by dropping thousands of tonnes of sand, lead, boric acid and other materials onto it from helicopters. Counter-productively, the effect of these materials was like lining the walls of a furnace with firebrick and increased the temperature of the molten fuel which was already melting its way through the reactor floor. Water that had been pumped into the building in a vain effort to extinguish the fire from the burning graphite moderator began to collect beneath the reactor and without the self sacrifice of two men ("liquidators") sent in wearing only divers' "wet suits" to release the valve and vent the radioactive water from the building, a thermal explosion would have ensued when the molten fuel contacted it, rendering an area of land around the plant occupying hundreds of thousands of square kilometers uninhabitable for hundreds of years. There are various estimated figures, but undoubtedly many lives were saved by these two men, who gave their own in so doing.
It is estimated (http://en.wikipedia.org/wiki/chernobyl_accident) that the unit 4 reactor contained around 180-190 tonnes of uranium oxide fuel and its fission products. With the reactor core exposed, oxygen came into contact with the very hot fuel and graphite moderator, causing the latter to catch fire. This resulted in a plume of radioactive smoke being borne upwards into the atmosphere, from where it was transported by weather currents over much of the western U.S.S.R. In Bulgaria, children were fed biscuits baked with zeolites in them - see my earlier listing "Zeolites - the stones that boil" - in an effort to remove any radioactive caesium and strontium they may have ingested. The adults were advised to drink a bottle of red-wine every day, in the belief or hope that the antioxidants in it would protect them against the effects of radiation. The fallout was further carried over western Europe, and as far as the western United States. 375 farms remain contaminated in the U.K. which hold 200,000 sheep - the sheep need to be moved to uncontaminated ground and grazed there for a few weeks before they are fit for market, and then only following an inspection by an appropriately accredited vet.
The human costs are immense. About 50 people died in the immediate stages; 28 from acute radiation exposure. Some children living in heavily contaminated areas received very high radiation doses of up to 50 Grays (Gy) from the absorption of iodine-131, a radioactive isotope with a half life of 8 days (far shorter than the biological half life for residence in the thyroid of 120 days). This, they ingested from locally produced milk which was heavily contaminated, and nine of them died from thyroid cancer. In total it is estimated that another 3,940 people are likely to die from cancer as a consequence of radiation exposure from Chernobyl. Over 300,000 people were rapidly displaced to safer areas after the disaster, 50,000 of them from the town of Pripyat where the nuclear power plant actually is (it lies 11 miles to the north west of the city of Chernobyl). In the intervening time many, mostly the old, have returned to their former homes.
The political impact of the Chernobyl disaster has been highly significant. It has been said that the event itself and the complications of dealing with it which were compounded by the prevailing Soviet secrecy of the time, helped to bring about the dissolution of the Soviet Union. It's initial influence was to turn nation populations and their leaders more steadfastly away from nuclear power. Ramping up the arms-race too, would have been unthinkable. Time and circumstances have moved on since then and the U.K. looks set to promulgate its nuclear capability, although the government is receiving somewhat conflicting advice. It's Chief Scientific Advisor advocates nuclear power on grounds of its low carbon emissions while a number of highly credible objections have been raised in a recent report by the Sustainable Development Committee. Assuming we do "go nuclear" I recall reading a while back that the government had planned an extra £10 billion for the purpose, and I see that £2 billion is planned to overhaul the Atomic Weapons Establishment at Aldermaston (http://www.awe.co.uk). The U.S. and Russia too, are each refurbishing their own nuclear defenses, though within guidelines agreed between them.
20 years on, I see that the nuclear issue, while lying dormant until recently, never entirely went away.
Monday, March 13, 2006
No Grounds for Nuclear?
Who's word will carry the more weight with Tony Blair? Sir David King, the U.K. government's Chief Scientific Advisor, or Sir Jonathan Porritt, Chair of the Sustainable Development Commission (SDC)? Jonathan Porritt was one of the founders of the Ecology Party (which became the Green Party) and then leader of Friends of the Earth. David King is of the opinion famously that "climate change [is] a greater threat than terrorism"and is in favour of nuclear power. Both he and James [Gaia] Lovelock support an expansion of nuclear power on the grounds that this energy source is free of CO2 emissions. It isn't quite, since it takes about 10 years to recoup for the CO2 emissions incurred in the construction of a nuclear plant, but over the entire operating lifetime it is estimated that it would produce only 20-40% of the CO2 emissions that a typical fossil fuel fired plant would, of similar generating capacity. However, as rich uranium ores become depleted and thinner supplies must be used, the CO2 cost of its extraction will rise, and so ultimately this argument, so often used in favour of nuclear, may find itself without foundation as most of the others have, e.g. "electricity too cheap to meter"!
The opposition view, espoused by Jonathan Porritt is based upon a number of separate considerations. Not surprisingly, the issue of nuclear waste remains paramount. Finding a safe long term means for disposing of nuclear waste is a matter of much current effort, as I have commented previously "Nuclear waste - if not in my back yard, then whose?" The nuclear industry seem convinced that a phased disposal programme will do the trick, but the SDC seems less certain that the problem is solved. I recall that the environmental group Friends of the Earth produced a lovely poster bearing an image of a Roman centurion and the caption: "If the Romans had had nuclear power, we'd still be guarding their waste." Nicely put, and the point is well made that nobody really wants it and no-one is entirely happy with any of the suggestions as to what to do with it. As I have already noted, the best solution appears to be sealing it into cement inside a copper container and burying it in bentonite clay (a good absorbent material) inside a concrete bunker (I didn't phrase it exactly in this fashion, but that's about the size of it).
As a matter of fact, if the Babylonians or the Egyptians had had nuclear power, their nuclear waste would still be a thorn in our sides, let alone the Romans - and what language would they have written the sign "Danger! High Level Nuclear Waste!" in? Presumably the Egyptians would have used Hieroglyphics; not much help to the common man such as myself, untrained in the arts of Egyptology.
The SDC have come up with further objections to the nuclear issue, however, not the least being the cost of the whole enterprise. If the scale of the task is stupendous, that is only matched by the quotation for it. It is estimated that the costs of decommissioning the 31 current reactors are £85 billion, or about £3 billion per unit. Having costed and funded quite a number of projects over the years, I am aware that the required level of financial support is apt to shift capriciously, often in ways that one could not reasonably have forseen. I will therefore assume a similar price per nuclear reactor for building it to that reckoned for pulling it down, i.e £3 billion. (This is probably as good a guess as any other). As noted in my previous listing, 14 new Sizewell B capacity (1.2 GW) reactors would be required to supplant the current nuclear output and hence should cost about £42 billion. If we were to go the whole hog of providing the entire nation's electricty by nuclear, we would need 54 of them, when the sum runs up to £182 billion. Now that is a hell of a lot of money in anybody's budget.
It is interesting that the authors of a new report have concluded that sea energy could provide 20% of the U.K.'s electricity requirements (http://news.bbc.co.uk/go/pr/fr/-/2/hi/ science/nature/4645452.stm), but not more than that. Coincidentally, 20% is about the proportion of U.K. electricity currently supplied by nuclear, and the inescapable thought surfaces that rather than replacing the existing 31 reactors by Sizewell B's at a cost, say, of £3 billion x 14 = £42 billion, investing that sum in wave farms and tidal stream installations might prove the more prudent course of action. It is thought that 50 terawatt hours (TWh) could be produced annually from wave power and another 18 TWh from tidal power, which equates to a mean generating output of (50+18) x 10*12/8760 (hours per year) = 7.8 GW, and is the equivalent of 19,500 2 MW offshore wind turbines (assuming a capacity factor of 0.2, i.e. only 20% of rated capacity is actually generated by the turbine because of variations in the wind speed relative to the dimension of the rotor). While 19,500 turbines placed 0.5 km apart (as they have to be in order to maximise efficiency) would occupy a band nearly 2 km thick around the entire coast of the U.K. mainland, I'm not sure how much sea area the wave and tidal installations would occupy. Any thoughts, anyone? For example, would we end up obstructing the Bristol Channel, say, with some leviathan tidal turbine?
The SDC report further cites issues of inflexibility, security and efficiency within its anti-nuclear manifesto. Nuclear is inflexible in the sense of tying the U.K. into a relatively inefficient centralised electricity system for the next 50 years, rather than a more efficient localised system of "micro-generation", such as has been adopted by the town of Woking, in Surrey. Essentially, if Woking were suddenly disconnected from the national grid, the lights would stay on, mainly through the use of solar panels and CHP (Combined Heating and Power) units. Even Her Majesty, The Queen, has had a couple of hydroelecrtic turbines installed in the River Thames, below Windsor Castle. It is also argued that the nuclear option is seen as a "quick fix", and distracts attention from issues of energy efficiency - i.e. using less of it in the first place - which is without doubt the direction we should (and will, as ultimately there is no choice) be going. The final objection concerns security, i.e. if the U.K. goes all out for nuclear, it cannot morally deny the same technology to other countries, and where lower safety standards pertain - I note that this year will witness the 20th anniversary of the nuclear catastrophe at Chernobyl - and so there is an increased risk of another such event if everyone gets their hands on nuclear.
An increased level of nuclear activity (no pun intended) also means an increased risk of terrorists getting hold of radioactive material, which they might fashion into a "dirty bomb", or of blowing-up a nuclear plant directly. These potential outcomes would be all the worse if the plants were powered by fast-breeder reactors, which run on plutonium, a very nasty material. A few grams of it and a hand grenade and probably an entire city like London would need to be evacuated, causing social and economic mayhem.
So my response to the SDC's conclusions is "Hear! Hear!" There is an intriguing tug of conflicts, though. Jonathon Porritt, Chair of the SDC, is telling Mr Blair "No", while his Chief Scientific Advisor Sir David King is saying "Yes". I wonder who's word will carry the greatest weight, since the government must decide "Yes" or "No"; there is no middle ground. As the two sets of arguments swing in the balance, which of them will seed the fruit of the government's actions? Personally, I suspect we will "go nuclear", but only time will confirm or discredit the veracity of this prediction.
The opposition view, espoused by Jonathan Porritt is based upon a number of separate considerations. Not surprisingly, the issue of nuclear waste remains paramount. Finding a safe long term means for disposing of nuclear waste is a matter of much current effort, as I have commented previously "Nuclear waste - if not in my back yard, then whose?" The nuclear industry seem convinced that a phased disposal programme will do the trick, but the SDC seems less certain that the problem is solved. I recall that the environmental group Friends of the Earth produced a lovely poster bearing an image of a Roman centurion and the caption: "If the Romans had had nuclear power, we'd still be guarding their waste." Nicely put, and the point is well made that nobody really wants it and no-one is entirely happy with any of the suggestions as to what to do with it. As I have already noted, the best solution appears to be sealing it into cement inside a copper container and burying it in bentonite clay (a good absorbent material) inside a concrete bunker (I didn't phrase it exactly in this fashion, but that's about the size of it).
As a matter of fact, if the Babylonians or the Egyptians had had nuclear power, their nuclear waste would still be a thorn in our sides, let alone the Romans - and what language would they have written the sign "Danger! High Level Nuclear Waste!" in? Presumably the Egyptians would have used Hieroglyphics; not much help to the common man such as myself, untrained in the arts of Egyptology.
The SDC have come up with further objections to the nuclear issue, however, not the least being the cost of the whole enterprise. If the scale of the task is stupendous, that is only matched by the quotation for it. It is estimated that the costs of decommissioning the 31 current reactors are £85 billion, or about £3 billion per unit. Having costed and funded quite a number of projects over the years, I am aware that the required level of financial support is apt to shift capriciously, often in ways that one could not reasonably have forseen. I will therefore assume a similar price per nuclear reactor for building it to that reckoned for pulling it down, i.e £3 billion. (This is probably as good a guess as any other). As noted in my previous listing, 14 new Sizewell B capacity (1.2 GW) reactors would be required to supplant the current nuclear output and hence should cost about £42 billion. If we were to go the whole hog of providing the entire nation's electricty by nuclear, we would need 54 of them, when the sum runs up to £182 billion. Now that is a hell of a lot of money in anybody's budget.
It is interesting that the authors of a new report have concluded that sea energy could provide 20% of the U.K.'s electricity requirements (http://news.bbc.co.uk/go/pr/fr/-/2/hi/ science/nature/4645452.stm), but not more than that. Coincidentally, 20% is about the proportion of U.K. electricity currently supplied by nuclear, and the inescapable thought surfaces that rather than replacing the existing 31 reactors by Sizewell B's at a cost, say, of £3 billion x 14 = £42 billion, investing that sum in wave farms and tidal stream installations might prove the more prudent course of action. It is thought that 50 terawatt hours (TWh) could be produced annually from wave power and another 18 TWh from tidal power, which equates to a mean generating output of (50+18) x 10*12/8760 (hours per year) = 7.8 GW, and is the equivalent of 19,500 2 MW offshore wind turbines (assuming a capacity factor of 0.2, i.e. only 20% of rated capacity is actually generated by the turbine because of variations in the wind speed relative to the dimension of the rotor). While 19,500 turbines placed 0.5 km apart (as they have to be in order to maximise efficiency) would occupy a band nearly 2 km thick around the entire coast of the U.K. mainland, I'm not sure how much sea area the wave and tidal installations would occupy. Any thoughts, anyone? For example, would we end up obstructing the Bristol Channel, say, with some leviathan tidal turbine?
The SDC report further cites issues of inflexibility, security and efficiency within its anti-nuclear manifesto. Nuclear is inflexible in the sense of tying the U.K. into a relatively inefficient centralised electricity system for the next 50 years, rather than a more efficient localised system of "micro-generation", such as has been adopted by the town of Woking, in Surrey. Essentially, if Woking were suddenly disconnected from the national grid, the lights would stay on, mainly through the use of solar panels and CHP (Combined Heating and Power) units. Even Her Majesty, The Queen, has had a couple of hydroelecrtic turbines installed in the River Thames, below Windsor Castle. It is also argued that the nuclear option is seen as a "quick fix", and distracts attention from issues of energy efficiency - i.e. using less of it in the first place - which is without doubt the direction we should (and will, as ultimately there is no choice) be going. The final objection concerns security, i.e. if the U.K. goes all out for nuclear, it cannot morally deny the same technology to other countries, and where lower safety standards pertain - I note that this year will witness the 20th anniversary of the nuclear catastrophe at Chernobyl - and so there is an increased risk of another such event if everyone gets their hands on nuclear.
An increased level of nuclear activity (no pun intended) also means an increased risk of terrorists getting hold of radioactive material, which they might fashion into a "dirty bomb", or of blowing-up a nuclear plant directly. These potential outcomes would be all the worse if the plants were powered by fast-breeder reactors, which run on plutonium, a very nasty material. A few grams of it and a hand grenade and probably an entire city like London would need to be evacuated, causing social and economic mayhem.
So my response to the SDC's conclusions is "Hear! Hear!" There is an intriguing tug of conflicts, though. Jonathon Porritt, Chair of the SDC, is telling Mr Blair "No", while his Chief Scientific Advisor Sir David King is saying "Yes". I wonder who's word will carry the greatest weight, since the government must decide "Yes" or "No"; there is no middle ground. As the two sets of arguments swing in the balance, which of them will seed the fruit of the government's actions? Personally, I suspect we will "go nuclear", but only time will confirm or discredit the veracity of this prediction.
Thursday, March 09, 2006
"No! to Nuclear."
The government's proposed fanfare event to revamp the nuclear industry now looks to be off; at least if they listen to their advisors, who conclude that "Nuclear Power is Dangerous, Expensive and Unwanted" ("The Independent", Tuesday 7th of March, Front Page). I am relieved to read this, since I concluded in a previous posting ("A Nuclear future?") that the idea was doomed, on the grounds that any actual expansion of the industry would require building even more than the number required to replace the existing 31 reactors due for decommissioning by 2025. This alone is a monumental undertaking, and to install sufficient of them on top of that to make any real difference in our CO2 emissions would render the exercise stupendous. To put this into context, the U.K.'s electricity generating capacity is around 64 GW (64,000 Mega-Watts), of which 22% is presently supplied from nuclear, or around 14 GW. (It should be noted that only about 2/3 of this capacity is used even during peak hours, but the maximum is the capacity we need to budget for, just in case, i.e. replacing like for like).
12 new Sizewell B capacity reactors (1.2 GW) could supply 14 GW of electricity and therefore replace the existing generation of reactors, most of which are of much lower output (down to about 0.4 GW = 400 MW). To produce the remaining 78% of electricity made mainly from gas (renewables only provide a couple of percent at most), we would need to build an additional 43 reactors of Sizewell B capacity, or 12 + 43 = 55 in all. Even then, it takes a nuclear power plant 10 years to pay-off its "carbon debt", i.e the budget of CO2 emissions incurred during the mining of the stone, and then in crushing it into a fine powder to make the required vast quantities of concrete; mining iron ore and then turning it into steel; then actually fabricating these materials into the required "Lego" pieces and finally bolting them all together; mining and enriching the uranium fuel and honing it into fuel rods; the same for the graphite control rods; constructing and installing the 50 miles or so of corrosion resistant nickel-steel pipes to make the heat transfer systems; providing pumps, motors and turbines etc.; installing the means for external water extraction - nuclear power plants are almost always built next door to a convenient river - and its subsequent safe discharge into the environment, etc. etc.
Even then, since electricity accounts for only 18% of the total energy used in the U.K., as I explain in my previous listing "Energy - not just Electricity" we would still be generating the other 80% of total energy using fossil fuels, and our colossal efforts to cut CO2 emissions using nuclear would only amount to 78% of 18% = 14%, which is nowhere near the 80-90% reduction in CO2 called for by 2030, in order to avoid catastrophic climate change. For that matter, some "experts" think it is already too late to avert this scenario, whatever we do now.
Add to this the fact that if the U.K. nation adopts this nuclear course alone, it will make practically no difference to global CO2 levels in the atmosphere, and if the whole world follows in similar fashion, it will run out of uranium in 4 - 7 years; alternatively, the material might be eked out for hundreds of years by turning it into plutonium in fast-breeder reactors, potentially arming terrorists (or anyone else with a grudge or wanting to make a ransom-bid of some kind).
The argument just doesn't hold, and the consequences of its acceptance would simply make the world even more dangerous. In our hands we have other choices, of energy efficiency and sustainable living. Of cutting our colossal energy use, mainly for transportation, but also by using more thermally efficient building materials, and deploying them in more effective construction strategies, fitted with less energy demanding devices (low-energy light-bulbs are a start). We could probably cut our entire energy use by 50%, in short order (at least compared to the timescale required for the putative nuclear expansion), and that is without the need for nuclear power at all.
I hope Mr Blair takes heed of his advisors, but we shall see. As I have mentioned before, there are other uses for uranium and plutonium which might fire-off a different agenda.
12 new Sizewell B capacity reactors (1.2 GW) could supply 14 GW of electricity and therefore replace the existing generation of reactors, most of which are of much lower output (down to about 0.4 GW = 400 MW). To produce the remaining 78% of electricity made mainly from gas (renewables only provide a couple of percent at most), we would need to build an additional 43 reactors of Sizewell B capacity, or 12 + 43 = 55 in all. Even then, it takes a nuclear power plant 10 years to pay-off its "carbon debt", i.e the budget of CO2 emissions incurred during the mining of the stone, and then in crushing it into a fine powder to make the required vast quantities of concrete; mining iron ore and then turning it into steel; then actually fabricating these materials into the required "Lego" pieces and finally bolting them all together; mining and enriching the uranium fuel and honing it into fuel rods; the same for the graphite control rods; constructing and installing the 50 miles or so of corrosion resistant nickel-steel pipes to make the heat transfer systems; providing pumps, motors and turbines etc.; installing the means for external water extraction - nuclear power plants are almost always built next door to a convenient river - and its subsequent safe discharge into the environment, etc. etc.
Even then, since electricity accounts for only 18% of the total energy used in the U.K., as I explain in my previous listing "Energy - not just Electricity" we would still be generating the other 80% of total energy using fossil fuels, and our colossal efforts to cut CO2 emissions using nuclear would only amount to 78% of 18% = 14%, which is nowhere near the 80-90% reduction in CO2 called for by 2030, in order to avoid catastrophic climate change. For that matter, some "experts" think it is already too late to avert this scenario, whatever we do now.
Add to this the fact that if the U.K. nation adopts this nuclear course alone, it will make practically no difference to global CO2 levels in the atmosphere, and if the whole world follows in similar fashion, it will run out of uranium in 4 - 7 years; alternatively, the material might be eked out for hundreds of years by turning it into plutonium in fast-breeder reactors, potentially arming terrorists (or anyone else with a grudge or wanting to make a ransom-bid of some kind).
The argument just doesn't hold, and the consequences of its acceptance would simply make the world even more dangerous. In our hands we have other choices, of energy efficiency and sustainable living. Of cutting our colossal energy use, mainly for transportation, but also by using more thermally efficient building materials, and deploying them in more effective construction strategies, fitted with less energy demanding devices (low-energy light-bulbs are a start). We could probably cut our entire energy use by 50%, in short order (at least compared to the timescale required for the putative nuclear expansion), and that is without the need for nuclear power at all.
I hope Mr Blair takes heed of his advisors, but we shall see. As I have mentioned before, there are other uses for uranium and plutonium which might fire-off a different agenda.
Tuesday, March 07, 2006
Razing the Rainforest.
It is thought that clearing and burning the rainforests may contribute as much as a quarter of the world's total human CO2 emissions. The rainforests form a band around the equator, of which the largest is located in the Amazon basin of South America, and occupies an area in size equal to half that of the U.S. Other major rainforested regions are found in western Africa, e.g. Congo, and in the South Pacific, e.g. Indonesia and the Philippines. According to one estimate (www.savetherainforest.org), only half the rainforests which now remain will exist by 2050, and there will be none left by 2060, such is their staggering rate of destruction. More than one and a half acres (about two football pitches worth) is lost each second of every day, which over a year translates into an area more than twice the size of Florida.
There is no single driver for rainforest destruction, but it is not simply a matter of poverty and overpopulation, although these are underlying issues. The ongoing actions mostly responsible are logging and agriculture. Thus, removing a felled tree causes more damage than merely the loss of the tree, as it is dragged out by tractors whose tracks break-up the soil such that it washes away in the heavy rainfall (up to 400 inches per year), which is intrinsic to a rainforest. Road building leads to further deforestation, and the problem is compounded by the fact that displaced farmers then use these access roads to get into the forest where they "slash and burn" to provide land for subsistence farming. Most of the timber that is cut by the loggers ends up being exported to rich countries where it is sold-on for sometimes hundreds of times the rate paid locally.
Pristine areas of rainforest are raised to the ground in order to provide land to grow cash crops, tree plantations and for grazing cattle. I recall watching a television programme entitled "Jungleburgers" some years ago, whose subject was the clearing of rainforest in South America to provide land on which cattle could be grazed as a raw material for the rising U.S. burger industry. This typifies the aspect that much of the crops of vegetables, wood and meat end up being sold to the wealthy industrialised nations, in some cases while the local population goes short of food. The intense nature of this agriculture, with its modern machinery, fertilisers and pesticides, denatures and drains nutrients from the soil, leaving it unfit and barren, at which point the whole process moves on to destroy further tracts of rainforest. It is the same consequence when poor farmers - "shifted" cultivators - are forced off their land by governments and large corporations, e.g. to grow coffee and sugar, and move onto forested land which they slash and burn, overcultivate and finally leave barren, whereupon they shift again.
In short, large scale agriculture, logging, building dams to provide hydroelectric power, mining and industrial development all contribute to forcing indigenous populations from their own lands. Indeed, shifted cultivators are now being blamed for up to 60% of tropical deforestation.
If the principally equatorial peoples are burning the rainforests to the extent of 25% of the global CO2 emissions that are engendered by humans on the one hand, and China, India and South American countries remain steadfast in an unprecedented programme of industrialisation fuelled by oil, gas and coal on the other (all of which will pump further CO2 into the atmospheric canopy), then our Kyoto pledges and milestones begin to appear puny and futile. Whatever actions the governments in the developed world decide upon (mindful that George Bush has stated that signing-up to Kyoto would "destroy the U.S. economy"), they are likely to be overwhelmed by emissions from the developing world.
There is no single driver for rainforest destruction, but it is not simply a matter of poverty and overpopulation, although these are underlying issues. The ongoing actions mostly responsible are logging and agriculture. Thus, removing a felled tree causes more damage than merely the loss of the tree, as it is dragged out by tractors whose tracks break-up the soil such that it washes away in the heavy rainfall (up to 400 inches per year), which is intrinsic to a rainforest. Road building leads to further deforestation, and the problem is compounded by the fact that displaced farmers then use these access roads to get into the forest where they "slash and burn" to provide land for subsistence farming. Most of the timber that is cut by the loggers ends up being exported to rich countries where it is sold-on for sometimes hundreds of times the rate paid locally.
Pristine areas of rainforest are raised to the ground in order to provide land to grow cash crops, tree plantations and for grazing cattle. I recall watching a television programme entitled "Jungleburgers" some years ago, whose subject was the clearing of rainforest in South America to provide land on which cattle could be grazed as a raw material for the rising U.S. burger industry. This typifies the aspect that much of the crops of vegetables, wood and meat end up being sold to the wealthy industrialised nations, in some cases while the local population goes short of food. The intense nature of this agriculture, with its modern machinery, fertilisers and pesticides, denatures and drains nutrients from the soil, leaving it unfit and barren, at which point the whole process moves on to destroy further tracts of rainforest. It is the same consequence when poor farmers - "shifted" cultivators - are forced off their land by governments and large corporations, e.g. to grow coffee and sugar, and move onto forested land which they slash and burn, overcultivate and finally leave barren, whereupon they shift again.
In short, large scale agriculture, logging, building dams to provide hydroelectric power, mining and industrial development all contribute to forcing indigenous populations from their own lands. Indeed, shifted cultivators are now being blamed for up to 60% of tropical deforestation.
If the principally equatorial peoples are burning the rainforests to the extent of 25% of the global CO2 emissions that are engendered by humans on the one hand, and China, India and South American countries remain steadfast in an unprecedented programme of industrialisation fuelled by oil, gas and coal on the other (all of which will pump further CO2 into the atmospheric canopy), then our Kyoto pledges and milestones begin to appear puny and futile. Whatever actions the governments in the developed world decide upon (mindful that George Bush has stated that signing-up to Kyoto would "destroy the U.S. economy"), they are likely to be overwhelmed by emissions from the developing world.
Monday, March 06, 2006
Water, Water Everywhere - But Less Than We Think.
There is a quotation from the Rime of the Ancient Mariner by Samuel Taylor Coleridge, in reference to the mariner on finding himself marooned on the open sea, "Water, water everywhere, nor any drop to drink", and which summarises the precarious nature of providing a sufficient water supply to a rapidly rising world population which, currently estimated at 6.5 billion, looks set to reach somewhere over 9 billion by 2050. The Earth is the "Blue Planet" because almost 70% of its surface is covered by water, but this is mainly salt-water as fills the seas and oceans, and which without desalination is unfit for drinking, washing in or for most industrial processes. Only 2.5% of the Earth's water is fresh, and about two thirds of that is locked-up in glaciers, mainly in the Antarctic and Greenland ice-sheets, and in permanent snow cover. Nonetheless on inspecting the detailed figures ("Freshwater Resources - The Atlas of Canada") the volume of liquid freshwater available appears vast, at close to 11 million cubic kilometers (km*3). However, near to 10.5 million km*3 of that is located in deep underground aquifers.
The principal sources of water available for human access are lakes, rivers, soil moisture and relatively shallow groundwater basins, from which it is estimated that only about 200,000 km*3 of water is available, which is less than 1% of all freshwater and only about 0.01% of all water on earth. Freshwater has been described as being "more precious than gold" (The Independent, 28th of February), meaning that while we can all live without gold, we certainly can't survive without enough water. Some of the statistics are salutary and some are shocking:
*More than one billion people live without access to clean, disease free water, and 2.4 billion of them (40% of the world's people) have no proper sanitation.
*6,000 children die each and every day from diseases associated with unsafe water, poor sanitation and lack of means for hygiene. This is the equivalent of 20 Jumbo jets crashing every day.
*80% of all diseases in the developing world are caused by unsafe water and poor sanitation.
*In developing countries around 90% of waste water is discharged untreated, which compounds the problem.
*One flush of a toilet in the West uses as much water as the average person uses in an entire day for drinking, cooking, cleaning and washing in the developing world.
*Overpumping deep ground water for drinking and irrigation has caused water levels to decline by tens of meters in many regions, so compelling people to use unsafe quality water instead.
The problem is different from those of other resources, and so there will not be "Peak Water" in analogy with "Peak Oil", since in our use of water we do not change its chemical form, but we do contaminate it and remove it from its reserves. Water is, as we know, renewable, since it is merely moved around by hydrogeological cycles. The pressure on water supply is driven mainly by the rising human population, not only for essential activities such as drinking, cooking, cleaning, hygiene and sanitation, but also as we must grow more food, hence imposing a greater demand on irrigation. In countries such as China and India there is a further demand of industrialisation, as their economies grow. The baseline recommended estimate of a per capita water requirement is 50 litres per day; however, it is possible to get by on about 5 litres for food and drink and another 25 for hygiene. Some countries use less than 10 litres per day (because they have no choice), e.g. Gambia, 4.5; Mali, 8; Somalia, 8.9; Mozambique, 9.3. In contrast, the average Briton gets through around 200 litres and their American counterpart 500 litres per day. It is obvious that rising living standards in the developing world will increase the overall demand for water.
Competition for water will lead to conflict and war, as it must for oil and gas. Potential flashpoint areas have been identified in the Middle East; China, India and Bangladesh; and in Africa, particularly Ethiopia and Egypt, as each side tries to garner more of its share. Climate change seems set to throw its own spanner in the works, through land erosion, sea level rise and flooding, thus causing the loss or contamination of freshwater sources. If global warming is caused (or significantly contributed to) by humans, it is another line in the text that we have to cut back on our use of fossil fuels. Ultimately we will have to, as their current supply becomes exhausted, but by then we may not have sufficient resources of fuel or water to face what lies ahead.
The principal sources of water available for human access are lakes, rivers, soil moisture and relatively shallow groundwater basins, from which it is estimated that only about 200,000 km*3 of water is available, which is less than 1% of all freshwater and only about 0.01% of all water on earth. Freshwater has been described as being "more precious than gold" (The Independent, 28th of February), meaning that while we can all live without gold, we certainly can't survive without enough water. Some of the statistics are salutary and some are shocking:
*More than one billion people live without access to clean, disease free water, and 2.4 billion of them (40% of the world's people) have no proper sanitation.
*6,000 children die each and every day from diseases associated with unsafe water, poor sanitation and lack of means for hygiene. This is the equivalent of 20 Jumbo jets crashing every day.
*80% of all diseases in the developing world are caused by unsafe water and poor sanitation.
*In developing countries around 90% of waste water is discharged untreated, which compounds the problem.
*One flush of a toilet in the West uses as much water as the average person uses in an entire day for drinking, cooking, cleaning and washing in the developing world.
*Overpumping deep ground water for drinking and irrigation has caused water levels to decline by tens of meters in many regions, so compelling people to use unsafe quality water instead.
The problem is different from those of other resources, and so there will not be "Peak Water" in analogy with "Peak Oil", since in our use of water we do not change its chemical form, but we do contaminate it and remove it from its reserves. Water is, as we know, renewable, since it is merely moved around by hydrogeological cycles. The pressure on water supply is driven mainly by the rising human population, not only for essential activities such as drinking, cooking, cleaning, hygiene and sanitation, but also as we must grow more food, hence imposing a greater demand on irrigation. In countries such as China and India there is a further demand of industrialisation, as their economies grow. The baseline recommended estimate of a per capita water requirement is 50 litres per day; however, it is possible to get by on about 5 litres for food and drink and another 25 for hygiene. Some countries use less than 10 litres per day (because they have no choice), e.g. Gambia, 4.5; Mali, 8; Somalia, 8.9; Mozambique, 9.3. In contrast, the average Briton gets through around 200 litres and their American counterpart 500 litres per day. It is obvious that rising living standards in the developing world will increase the overall demand for water.
Competition for water will lead to conflict and war, as it must for oil and gas. Potential flashpoint areas have been identified in the Middle East; China, India and Bangladesh; and in Africa, particularly Ethiopia and Egypt, as each side tries to garner more of its share. Climate change seems set to throw its own spanner in the works, through land erosion, sea level rise and flooding, thus causing the loss or contamination of freshwater sources. If global warming is caused (or significantly contributed to) by humans, it is another line in the text that we have to cut back on our use of fossil fuels. Ultimately we will have to, as their current supply becomes exhausted, but by then we may not have sufficient resources of fuel or water to face what lies ahead.
Sunday, March 05, 2006
Wind Power - An Unlikely Question of Scale.
In a previous listing ("A Hydrogen Economy - Is it Economic?") I calculated that we would need around 720,000 land based wind turbines, rated at 0.5 MW capacity, or 180,000 sited offshore and rated at 2 MW, in order to generate sufficient hydrogen to substitute for the quantity of liquid petroleum fuel that is currently used for transportation in the U.K. To place these totals in context, as a further assessment of the feasibility of the enterprise, I will now calculate the physical dimensions of the required "wind farms" to accommodate these numbers of turbines. In making my original estimate, I deliberately used the raw data, without taking account of energy losses, which are always incurred when converting one form of energy to another; a consequence of the Second Law of Thermodynamics. The overall loss from electricity to hydrogen to wheel (or wing, since 22% of the budget is taken by the aviation industry), I estimate to be around 50%; assuming a 70% loss in the electrolysis step, and the same in "burning" hydrogen in fuel cells to power vehicles: i.e. 70% of 70% = 49%. This is also the conclusion of Ulf Bossel, the founder and organiser of the European Fuel Cell Forum, based in Switzerland. (His article "The Hydrogen Illusion" is most illuminating).
Therefore, I must revise my original numbers upwards by a factor of two, and hence we actually need to find room for 1,440,000 0.5 MW turbines on land, or 360,000 2 MW turbines on offshore sites. Now, wind turbines can't be simply stacked together side by side, back to back. This is because, in effect, each turbine obstructs the wind flow in reaching the one behind it, unless they are placed something like 0.3 to 0.5 kilometers apart, depending on the diameter of the turbine blade. Placed on land 0.5 km apart (the arithmetic becomes a bit more complex if some other distance is chosen), 1,440,000 0.5 MW turbines would occupy an area of 360,000 square kilometers. Since the entire land area of the U.K. mainland is only 244,000 square kilometers, we are already of course 50% short of anywhere to put them, even if we covered the entire country with wind turbines, which I doubt would be a popular option with estate agents and the tourism industry!
So, let us consider the alternative option of a potential "offshore investment". As a rough calculation of the coastal periphery of the U.K. mainland, I will take the straight line distance from north to south as 680 miles and that from east to west as 200 miles = 1760 miles in total = 2800 km. We now need only to accommodate 360,000 turbines each metered at 2 MW capacity, since they are offshore and hence out of sight (and hearing) and hence out of mind. A single band spaced 0.5 km apart would accommodate 5,600 turbines, and so a depth of them of 64 around the entire country would accommodate 360,000 turbines as we require it to, which equates to a thickness of 32 km. If we set the location of the wind farm at 5 km out to sea in order to avoid offending the locals (coast dwellers around the entire country) this would stretch over onto the French coast at the English Channel, the point of closest approach between the two countries, and would surely comprise a severe obstruction to shipping!
My point is that renewable energy is dispersed not concentrated, unlike, oil, coal, gas or uranium, and will therefore never replace these other fuels at our current rate of usage of them. We have to live differently (less energy intensively) if we are to survive.
Therefore, I must revise my original numbers upwards by a factor of two, and hence we actually need to find room for 1,440,000 0.5 MW turbines on land, or 360,000 2 MW turbines on offshore sites. Now, wind turbines can't be simply stacked together side by side, back to back. This is because, in effect, each turbine obstructs the wind flow in reaching the one behind it, unless they are placed something like 0.3 to 0.5 kilometers apart, depending on the diameter of the turbine blade. Placed on land 0.5 km apart (the arithmetic becomes a bit more complex if some other distance is chosen), 1,440,000 0.5 MW turbines would occupy an area of 360,000 square kilometers. Since the entire land area of the U.K. mainland is only 244,000 square kilometers, we are already of course 50% short of anywhere to put them, even if we covered the entire country with wind turbines, which I doubt would be a popular option with estate agents and the tourism industry!
So, let us consider the alternative option of a potential "offshore investment". As a rough calculation of the coastal periphery of the U.K. mainland, I will take the straight line distance from north to south as 680 miles and that from east to west as 200 miles = 1760 miles in total = 2800 km. We now need only to accommodate 360,000 turbines each metered at 2 MW capacity, since they are offshore and hence out of sight (and hearing) and hence out of mind. A single band spaced 0.5 km apart would accommodate 5,600 turbines, and so a depth of them of 64 around the entire country would accommodate 360,000 turbines as we require it to, which equates to a thickness of 32 km. If we set the location of the wind farm at 5 km out to sea in order to avoid offending the locals (coast dwellers around the entire country) this would stretch over onto the French coast at the English Channel, the point of closest approach between the two countries, and would surely comprise a severe obstruction to shipping!
My point is that renewable energy is dispersed not concentrated, unlike, oil, coal, gas or uranium, and will therefore never replace these other fuels at our current rate of usage of them. We have to live differently (less energy intensively) if we are to survive.
Friday, March 03, 2006
Fire in the Caucasus.
I am pleased to note that my conclusions that the days of burning oil-based fuels with profligate abandon are numbered (e.g. my posting: "Peak Oil") have now been confirmed by the government's Chief Scientific Advisor, Professor Sir David King. He also thinks that this state of affairs will lead to a drastic reduction in transportation use, certainly by 2055, and as I have illustrated in this series of listings ("A Hydrogen Economy - is it Economic?; "Bio-hydrogen: a Preposterous Idea"; "Biofuels - How Practical are They?"), substituting oil or gas by hydrogen on the scale that would be required to meet current demand is simply impractical using renewables, and probably so using nuclear. The need to develop localised communities and economies is now paramount, and our elected leaders need to make tough decisions about how we all do in fact live, and may thus continue to do so. By living in relatively small communities of perhaps 10,000 - 20,000, which provide and are provided for by local farms and enterprises, we could save about 90% of current fuel usage. Additionally, if our activities were to be conducted (no pun intended) in thermally much more efficient buildings, perhaps 50% of the total national energy budget could be saved (e.g. the "40% House" being researched at Oxford, and the "Passivhaus" concept in Germany).
As I have stressed, electricity provides only 18% of the U.K.'s total energy, and is generated using mostly gas, but also coal, nuclear (22%) and a miniscule amount (not more than a couple of percent) of renewables; the remaining 82% of total energy in produced also mainly from gas, but 26% of that national total is costed in terms of liquid petroleum fuel for transportation and significantly (6%) for the growing aviation market. It is not thought that a peak in gas production will occur prior to about 2100, and so it is "Peak Oil" that is our most pressing issue, though gas supplies, which the U.K. now imports following the substantive exhaustion of our North Sea reserves, might become artificially restricted by political or market actions, as happened in the Ukraine recently.
Although the Ukraine is not on the Caucasus (in contrast to the title of this article) it was subject to a massive turn-off of its gas recently and it seems now to be the case in Georgia too, which is part of the Caucasus region; hence my title, and according to my connection with the Republic of Armenia, which lies on that central geography too. Armenia is a small land-locked country, of remarkable charm, despite widespread poverty. The northern part is a rugged landscape of light-brown porous rock, comprising large deposits of "tuff", a mineral rich in zeolites. Gas supplies into Armenia from Georgia are a precarious affair, as the pipeline is frequently blown-up by various factions with their own agendas. The only stable gas pipeline to Armenia is from Iran and runs into the South of the republic.
Conspiracy theories abound about the recent explosion which ruptured the gas pipeline from Russia into Georgia, and now Chechnya has suffered a similar injury to its supply, for which acts of sabotage are blamed. Supplying fuel inside the Caucasus is all a complex web of supply and dependence, of restriction and diversion, of delivery and determination, of politics and power, of coercion and will. Meanwhile, those caught in its strands survive by the fire of kerosene and wood, as happened in Armenia in the especially harsh winter of 94/95, when the forests became devastated.
Providing fire in the Caucasus is a microcosm; a warning of what is to come for us all. A shift of economic and political fuel, according to resource, and a shift of world power into the grip of countries which command the primary resource of supply. It is already on its way to the West, in the planned gas pipelines from the Caucasus into Germany and Italy. Whatever the precise mechanism we will all ultimately be faced with a similar situation to that which occurred in Cuba, who were forced to deal with the aftermath of its abrupt curtailment of fossil fuel supply from Russia. The consequence was the rapid adoption of sustainable living in small communities. This is our future, either by choice or by default. We have no choice in this outcome.
As I have stressed, electricity provides only 18% of the U.K.'s total energy, and is generated using mostly gas, but also coal, nuclear (22%) and a miniscule amount (not more than a couple of percent) of renewables; the remaining 82% of total energy in produced also mainly from gas, but 26% of that national total is costed in terms of liquid petroleum fuel for transportation and significantly (6%) for the growing aviation market. It is not thought that a peak in gas production will occur prior to about 2100, and so it is "Peak Oil" that is our most pressing issue, though gas supplies, which the U.K. now imports following the substantive exhaustion of our North Sea reserves, might become artificially restricted by political or market actions, as happened in the Ukraine recently.
Although the Ukraine is not on the Caucasus (in contrast to the title of this article) it was subject to a massive turn-off of its gas recently and it seems now to be the case in Georgia too, which is part of the Caucasus region; hence my title, and according to my connection with the Republic of Armenia, which lies on that central geography too. Armenia is a small land-locked country, of remarkable charm, despite widespread poverty. The northern part is a rugged landscape of light-brown porous rock, comprising large deposits of "tuff", a mineral rich in zeolites. Gas supplies into Armenia from Georgia are a precarious affair, as the pipeline is frequently blown-up by various factions with their own agendas. The only stable gas pipeline to Armenia is from Iran and runs into the South of the republic.
Conspiracy theories abound about the recent explosion which ruptured the gas pipeline from Russia into Georgia, and now Chechnya has suffered a similar injury to its supply, for which acts of sabotage are blamed. Supplying fuel inside the Caucasus is all a complex web of supply and dependence, of restriction and diversion, of delivery and determination, of politics and power, of coercion and will. Meanwhile, those caught in its strands survive by the fire of kerosene and wood, as happened in Armenia in the especially harsh winter of 94/95, when the forests became devastated.
Providing fire in the Caucasus is a microcosm; a warning of what is to come for us all. A shift of economic and political fuel, according to resource, and a shift of world power into the grip of countries which command the primary resource of supply. It is already on its way to the West, in the planned gas pipelines from the Caucasus into Germany and Italy. Whatever the precise mechanism we will all ultimately be faced with a similar situation to that which occurred in Cuba, who were forced to deal with the aftermath of its abrupt curtailment of fossil fuel supply from Russia. The consequence was the rapid adoption of sustainable living in small communities. This is our future, either by choice or by default. We have no choice in this outcome.
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