One of the dreams of the global warming crowd is carbon free energy. Being in the energy industry and knowing that oil is beginning to run out, I am always interested in what articles say about how we are going to get more energy. And I am always, always, disappointed by what I read.
This month's Scientific American has an artricle by Mark Z. Jacobson and Mark A. Delucchi, "A path to Sustainable Energy by 2030" Scientific American Nov 2009, p. 58-65. What I notice in articles which tell us how we are going to get off carbon is a constant use of worlds like "could", and "might". These words are used to 'solve' every problem.
"Photovoltaic cells rely on amorphous or crystalline silicon, cadmium telluride, or copper indium selenide and sulfide. Limited suplies of tellurium and indium could reduce the prospects for some types of thin-film solar cells, though not for all; the other types might be able to take up the slack.Large-scale production could be restricted by the silver that cells require, but finding ways to reduce the silver content could tackle that hurdle. Recycling parts for old cells could ameliorate material difficulties as well."
"Three components could pose challenges for building millions of electric vehicles: rare-earth metals for electric motors, lithium for lithium-ion batteries and platinum for fuel cells. More than half the world's lithium reserves lie in Bolivia and Chile. That concentration, combined with rapidly growing demand, could raise prices significantly. More problematic is the claim by meridian International Research that not enough economically recoverable lithium exists to build a global electric-vehicle ecnomy. Recycling could change the equation, but the economics of recycling depend in part on whether batteries are made with easy recyclablility in mind, an issue the industry is aware of. The long-term use of platinum also depends on recycling; current available reserves would sustain annual production of 20 million fuel-cell vehicles, along with existing industrial uses, for fewer than 100 years." Mark Z. Jacobson and Mark A. Delucchi, "A path to Sustainable Energy by 2030" Scientific American Nov 2009, p. 62
A couple of years ago an article discussing rare-earth resources claimed that we only have a 5-10 year supply of indium at current levels of usage.
"Take the metal gallium, which along with indium is used to make indium
gallium arsenide. This is the semiconducting material at the heart of a
new generation of solar cells that promise to be up to twice as
efficient as conventinal designs. Reserves of both metals are disputed,
but in a recent report Rene Kleljn, a chemist at Leiden University in
the Netherlands, concludes that current reserves 'wouldnot allow a
substantial contribution of these cells' to the future supply of solar
electricity. He estimates gallium and indium will probably contribute to
less than 1 percent of all future solar cells--a limitation imposed
purely by a lack of raw material." David Cohen, Earth Audit," New
Scientist May 26, 2007, p.35
Recycling won't help that. The same article noted that silver reserves are good for about another 15-20 years at current rates of usage. Yes, recycling will help, but it will stop massive solar conversions. One estimate said that to make a 5% contribution to electrical generation, 30% of the world's silver production would be consumed.source
When these authors claim that platinum will last for fewer than 100 years, that is not very forthcoming.
"Suppose that the 500 million vehicles estimated to be in use worldwide in 2000 were converted to fuel cell operation operating on pure hydrogen (i.e., no reforming of fuel needed), that the platinum requirement was 0.4 g/kW, that the average vehicle power was 75 kW, that the fuel cell life was 10 years with a 90% recycling rate, and that recycling achieved 50% recovery of the platinum content. The platinum stock-in-use for these vehicles would be 15 Gg. Maintaining this stock would require a flow of new metal into use of ~1 Gg per year. If all of the remaining lithospheric stock of platinum were devoted to operating a fleet of 500 million vehicles with fuel cells, the platinum resource in the lithosphere would sustain this fleet for ~15 years. There would be competition for this platinum for use in jewelry, stationary power fuel cells, industrial catalysts, and catalytic converters for motor vehicles still using petroleum fuel.
R.B. Gordon et al, “Metal Stocks and Sustainability,” PNAS v.103(2006):5:1213
How much would the price rise? The world simply doesn't have lots of platinum.
One of the things that these energy guys don't think about is the increasing amounts of energy required to refine the lower and lower quality ores of all types. In the 1930s, iron ores had 60% iron. Today it is 25%
"The hematite ore of the Mesabi Range in Minnesota contained 60 percent iron. But now it is depleted and society must use lower-quality taconite ore that has an iron content of about 25 percent. [ ]
The average energy content of a pound of coal dug in the US has dropped 14 percent since 1955. [ ]
In the 1950s, oil producers discovered about fifty barrels of oil for every barrel invested in drilling and pumping. Today, the figure is only about five for one. Sometime around 2005, that figure will become one for one. Under that latter scenario, even if the price of oil reaches $500 a barrel, it wouldn't be logical to look for new oil in the US because it would consume more energy than it would recover. [ ]http://www.dieoff.org/page175.htm#_edn6
Jay Hansen, Energy Magazine, Spring 1999,p.
“Figure 3-16 shows what mineral depletion looks like-gradually decreasing ore concentration. Figure 3-17 shows the consequence of depletion. As the amount of usable metal in the ore falls below 1 %, the amount of rock that must be mined, ground up, and treated per ton of product rises with astonishing speed. As the average grade of copper ore mined in Butte, Montana, fell from 30% to 0.5% the tailings produced per ton of copper rose from 3 tons to 200 tons. This rising curve of waste is closely paralleled by a rising curve of energy required to prooduce each ton of final material. Metal ore depletion hastens the rate of fossil fuel depletion.” Donella H. Meadows, Dennis L. Meadows, Jorgen Randers, Beyond the Limits, (Post Mills, VT: Chelsea Green Publishing Co., 1992), p. 84-85
Such realities require more and more energy.
Solving problems by wishful thinking, as is done in this article is not going to actually work but it feels so good saving the planet and even gets you an article in Scientific American.