Tuesday, July 22, 2008

Clean Coal Conundrum.

As gas prices rise the UK government thinks that switching to "clean coal" (sometimes called "green coal") is the solution. The necessary rider to this kind of technology is that most of the carbon will be captured at the other end and stored long-term, in natural underground cavities, rather than letting it escape into the atmosphere as CO2. The Royal Society (Britain's Academy of Sciences) has endorsed a call from the Environment Audit Committee (EAC) that there should be "bold leadership" in the matter of using coal as a source of energy but noted the government "appears paralysed".

A coal-fired power station produces around twice the amount of CO2 that a gas-fired station does of equivalent generating capacity, and if carbon capture and storage (CCS) technology is fitted as well, the process requires another 10 - 40% worth of fuel to be burned. Put another way, it might take building a third station for every two to power the CCS for them all. The EAC heard evidence that there may be five or six new coal-fired stations built in the U.K. by 2015, although this does appear dubious since it takes around 10 years to build one.

The EAC has told the government that it must set a clear date by which companies must implement CCS or close their coal-plants down. It stresses that clean coal is a "fig leaf" whereby the government is able to claim green credentials in developing a low-carbon future (in line with EU greenhouse-gas targets) despite the fact there is no guarantee that CCS will will installed, which is an untried technology as yet, on the significant scale, and is also going to be expensive. Now that much is guaranteed.

"Unless there is a dramatic technological development, coal should be seen as the last resort, even with the promise of CCS", so concludes the EAC report. Tim Jones, climate policy officer with the World Development Movement, commented: "The government should not be relying on CCS - an unproven technology - to justify new coal power stations."

There is an issue too, of where this coal might come from since Britain only produces around a third of the coal it uses and hence a dependency on imported fuel remains.

Related Reading.
"Clean deadline call on coal power." By Richard Black. http://news.bbc.co.uk/1/hi/sci/tech/7518311.stm

4 comments:

Anonymous said...

To answer " where will the coal come from ?", it won't be deep mined, open cast or imported (all too expensive) but from UCG. The UK reserves of 'unmineable' coal accessible by this method are several times the official estimates of 'mineable' coal. CO2 capture is also much easier / cheaper from UCG than post-combustion from power station chimneys, HMG's preferred option. Please check out our site at bcgenergy.co.uk. kind regards Alan

Professor Chris Rhodes said...

Hi Alan,

that's very interesting! I had heard there is 190 billion tonnes of coal all told under these islands (including under the North Sea), but only 1.5 billion tonnes in known accessible mine holdings.

It is also my understanding that we use about 60 million tonnes of coal a year - 40 Mt imported and about 10 Mt each from near-surface and deep mines.

Are these figures accurate - can you confirm or otherwise?

So, we are going to go for coal gasification then? This is the first serious suggestion I have heard of UGC. I know there was a pilot study done in Derbyshire in the '50's but it is interesting and encouraging that the UK will go this way on the grand scale.

The NCB didn't follow-up this Derbyshire trial on grounds that it was too expensive, but not any more with gas/oil prices as they are and set to rise further.

I'll check the web-site.

Many thanks!

Chris.

Anonymous said...

If you shut down "dirty coal", what is proposed to replace it? Remember, Wind, has variable output, and is hardly ever in sync with the usage patterns of humans, thus the wind blows when power demand is least, and other way around...or does not blow at all. In either case, a BACK-UP generations system is required to provide un-interrupted power...something so very few people comprehend. You must pay for, build, and operate TWO power systems to get ONE result.

In the case of both SOLAR and WIND, although renewable, BOTH only AUGMENT existing generation resources, they **DO NOT** REPLACE them.

This falacy is the most propigated one and is so misleading to the general public.

IF the CO2 climate demise claims are bogus, then no problem with continued coal. IF CO2 is valid, then there are very few generation technologies which meet society's appitete for energy.

Thus the "N" word creeps into conversations...since it is a known, comercially viable, economical way to supply power.

There are NO cheap solutions.
There are NO quick solutions.
There are NO easy solutions.

Everyone should wake up out of the fantasy, face facts, and realize that the costs of everything are going to go up....way up...no matter what.

Just make sure you get what you pay for and not to simply make some special group rich at the expense of the many.

Professor Chris Rhodes said...

Fair comment! I think running-out of cheap oil and gas is the greatest and most immediate threat to life on earth even if the GW claims are true.

I note there is a large group of protestors at the Kent coal-fired plant today, who probably don't realise the pressing need for coal, nuclear and all other forms of power-production, given our national electricity demand.

I agree - there is no easy solution. This is my sad conclusion. When I stated this blog I hoped there was.. but there we are.

Regards,

Chris.