[Charles has written about cutting-edge science for Wired Magazine for about five or six years. I'll give him the last word. Previous Politech message: http://www.politechbot.com/p-03023.html --Declan] --- Date: Sat, 12 Jan 2002 12:11:33 -0500 (EST) From: Charles Platt <cpat_private> To: Declan McCullagh <declanat_private> Cc: cpat_private Subject: Re: FC: Responses to are Feds wasting tax money on hydrogen full cells? In-Reply-To: <5.1.0.14.0.20020112113414.00a277d0at_private> Hi Declan-- You may use this on Politech if you wish. Virtually every energy project financed by government, from the Tennessee Valley Authority to methanol, has been expensive and has produced questionable benefits. Where hydrogen is concerned, the energy required to split the H2-O2 bond is comparable to the energy released by burning the H2 or recombining it with O2. Very basic chemistry here! So, extraction from water is not a sensible option. The other option is to find a naturally occurring burnable form of hydrogen, such as methane. Depending how you use it, you may avoid creating much carbon dioxide, as in a fuel cell. This is desirable from the point of view of the greenhouse effect. But fuel cells have major problems that people seldom write about. For instance, the cells do not react well if you switch them on and off! Also you are still consuming a nonrenewable resource, unless you find a way to bottle the methane created from, e.g., animal manure. I don't believe this is practical. Nor do I believe hydrogen pipelines make any sense at all, least of all in a new era of terrorism. Nor would I be happy about driving a vehicle containing hydrogen, or methane, under pressure. A pressure vessel is heavy and dangerous, not just from the point of view of fire and explosion, but as a massive object which will tear itself loose in any severe collision, becoming a lethal missile. This is not what you want in a fast car (although it may be tolerable in buses and delivery vehicles). But of course, Greens don't want us to drive fast cars. And this is the real heart of the matter. The environmental issue as always is driven as much by emotions as by logic. In 1970, The Limits to Growth predicted exhaustion of oil reserves around now. Yet today, known reserves are actually greater than in 1970. I would be surprised if oil runs out within a century. In the meantime, gasoline engines have been refined to the point where a hybrid gasoline-electric vehicle (in which the gasoline engine runs within a narrow range of revs, and can thus be optimized for this purpose) produces virtually zero emotions other than carbon dioxide. The latter is a problem only so long as we view global warming as something which can only be prevented rather than cured. In fact there are various options for curing global warming, by spreading vapor or dust in the very high atmosphere, thus reflecting slightly more sunlight. But again no one wants to think about this, because it would enable us to continue in our "wasteful" ways. It's another issue driven by emotions rather than science. As for oil depletion, when it occurs, the obvious answer is nuclear power and electric cars. Battery-driven vehicles from major auto manufacturers have been ridiculously expensive and disappointing in their performance purely because the manufacturers are locked into a mindset dictated by market research, in which consumers always mention range between recharges as a primary concern. Thus the EVs are weighed down with huge expensive battery packs. But what people say, and what people do, are very different. People say they want to drive 200 miles between recharges, while in reality they drive typically 20 to 40 miles per day, commuting, or shopping or taking the kids to school. An EV with a 40-mile range needs one-third the battery power of an EV with an 80-mile range (it's so much lighter, the fewer batteries take it farther), and can have a spirited performance, at a reasonable price. I've driven one, built by a California EV fanatic. It was entirely practical. We will still need a different kind of vehicle for long-distance driving. But this need could be satisfied by a second car with a different power supply, and the car could be rented rather than purchased, so that it doesn't spend most of its life sitting in a garage waiting for that one family vacation each year. Also, in the future, rapid recharging of electrics may become feasible, in which case long-distance electrics make sense, especially in smaller European nations with a high population density that could support frequently spaced recharging stations. Electrics would not merely shift the pollution problem from the vehicle to the generating facility, because much electricity is generated by hydro power, and could be generated by nuclear power. Also, electrics would typically recharge at night when there is surplus generating capacity. And a coal-fired electricity generating plant is much cleaner and more efficient than an internal combustion engine, because of economies of scale, and because internal combustion is inherently less efficient and more polluting than the external combustion (i.e. furnaces) in power generating facilities. I wrote about all this, many years ago for Wired, but the fuels debate is a rich field for wacky ideas and pet theories, so the nonsense continues. It is also a rich field for politicians seeking popular issues at which money can be thrown; which is where we came in. --Charles ------------------------------------------------------------------------- POLITECH -- Declan McCullagh's politics and technology mailing list You may redistribute this message freely if you include this notice. Declan McCullagh's photographs are at http://www.mccullagh.org/ To subscribe to Politech: http://www.politechbot.com/info/subscribe.html This message is archived at http://www.politechbot.com/ -------------------------------------------------------------------------
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