In some of my postings about the considerable limitation in the rate at which platinum can be recovered in relation to the amount of it we would need to make fuel cells for vehicles powered by hydrogen, I have assumed there are 600 million "cars" on the highways of the world, but this does in fact err on the side of caution. At the end of 2004, the figure was closer to 500 million cars and 200 million trucks etc. (up from around 40 million vehicles altogether in 1945), and 500 million of that total are fitted with cats. It is less demanding in terms of platinum to make a cat than a fuel cell, since the latter use up to 100 g of platinum per unit, e.g. that employed by Daihatsu.
The US based consulting firm TIAX have concluded that world platinum will not run-out, and certainly if the amount of Pt required in fuel cells falls (as is claimed, to perhaps one third of the amount currently used, and there are far more optimistic claims too of about one sixth), there would be enough of it in existing mine-holdings to make those 680 million fuel cells, but it is a rare metal which is only laboriously wrestled from its ore, usually over a period of about 6 months. 88% of world Pt comes from 2 mines in SA and most of the rest from another mine in the Urals. Enhancing new Pt output will be very difficult if not impossible in any significant amount.
It is highly unlikely that we will give-up all our jewelry and we need the existing cats to keep NOx and other traffic exhaust-emissions within acceptable limits. It is difficult to predict the date of breakthroughs in research and even more so to predict timelines for their commercial development. Notwithstanding, I am looking at a period of about 10 years, by when according to almost all estimates we will be past the point of peak oil production, and oil-supplies worldwide will be down, probably to 90 - 95% of current levels, which is really going to hurt our lifestyle. I do not believe we will have enough platinum to make sufficient fuel cells by then, to offset a decline in oil-powerd internal combustion engines, nor enough hydrogen to fuel them, certainly not from renewable sources.
In this interim of the "Oil Dearth Era", we cannot expect fuel-cells to help us much, and even if we surrendered half the world's new platinum (75 tonnes) plus another 30 tonnes (which would involve taking 24 million vehicles off the road once their cats had been scrapped) from recycled platinum, we could introduce an optimistic 105 x 10^6 g/say 60 g/vehicle = 1.75 million fuel cells per year. If we could do this starting now, in a 10 year period, we could have 17.5 million new "fuel cell" cars, but we would have taken 240 million off the road for their cats. This would leave us with 680 - 240 = 440 oil-powered vehicles left (having scrapped their cats for the Pt they contain, and ignoring those that had been stolen) plus 17.5 million hydrogen-powered cars, making 67%, or two thirds of the current number.
Rising fuel prices and shortages of fuel will force that number down significantly, and in 25 years we would be left with 44 million hydrogen vehicles, but if the cats are scrapped for their Pt, that will require the loss of 600 million oil-powered vehicles, or most of the current number. These sums are for "fun" (not that I find any of this even marginally amusing) and are open to criticism, but I am simply trying to stress the point that the hydrogen economy, if it could be implemented in the face of Oil Dearth will only provide for less than 10% of current levels of transportation, while the shortages of oil expected over that same 25 years and the inexorably rising financial and energy costs of its extraction and processing will force a majority of current vehicles off the roads.
In the immediate future (a period of 10 years, starting now) we can forget about hydrogen; while making diesel from biomass and from algae by so-called second generation processes offers some hope (and does not compromise food production, unlike first generation biofuels, which ultimately must do), probably only 15% of current transport levels can be so maintained. The notion that we can simply change-over almost overnight to hydrogen or to anything else on a scale that will allow us to hang-onto our current measure of energy profligacy is simply wrong. Accordingly, society will begin to relocalise into smaller self-sustaining communities - if people can't move around so easily they will stay where they are, and will need to find a means for living at the local level. Deconstructing populous cities will be the most testing effort, and may prove impossible, but the world needs a clear plan of cooperative transformation not further war and bloodshed over relentlessly depleting resources.
Related Reading.
[1] "Thieves target catalytic converters as platinum prices soar." CBC News. http://www.cbc.ca/canada/montreal/story/2008/01/10/qc-catalyticconverter0110.html?ref=rss.
[2] "Carmakers gear up for the next shortage - platinum." By James Mackintosh and Kevin Morrision. Originally, FT.com. http://www.theminingnews.org/news.cfm?newsID=800.
[3] "Scrap PGM recovery seen booming in '90's - platinum group metals - scrap." An older article. http://findarticles.com/p/articles/mi_m3MKT/is_n192_v97/ai_7992455.
[4] "Significance of fuel cells to the platinum market." http://www.platinummetalsreview.com/dynamic/question/view/11754.
[5] "Car of the future may stall at start." Business Day. http://www.arizonaenergy.org/News%2005/News%20July05/car_of_the_future_may_stall_at_s.htm
No comments:
Post a Comment