renewable energy > features > renewable options 2: fuel cells
Renewable options 2: Fuel CellsPosted: 06 Nov 2002
The clean car is coming
by Peter Hoffmann
"No car company will be able to thrive in the future with 100 per cent dependency on internal combustion engines." The speaker was the chairman of the world's largest car maker, General Motors, a company generally regarded as fairly conservative and not given to rash assertions. Thus, the comments by GM CEO John F. Smith a few years ago at the Detroit Auto Show, predicting that environmental pressures will force a fundamental shift in the automotive industry by moving away from gasoline-fuelled cars to fuel cells, were seen as a sort of official seal of approval.
The development of fuel cells, these marvellous, silent, environmentally benign electrochemical engines that provide electrical power for the Space Shuttle, is moving ahead with a vengeance. For transportation, they are poised to become commercial realities for buses first and cars a little later. In stationary use, the race is on to develop efficient, economical plants for utilities, hospitals, office buildings and telecommunication networks; for computer systems, for providing cheaper, clean power to forsaken Alaska villages or remote Pacific islands.
Fuel Cells are about twice as efficient as internal combustion engines, and they are genuine zero-emitters when operating on pure hydrogen (think of hydrogen as natural gas minus carbon, the villain in the greenhouse gas carbon dioxide), very low pollution emitters and less efficient when running on low-carbon-content natural gas or methanol. All fossil fuels, though, can be seen as 'hydrogen carriers' from which hydrogen can be extracted.
Around the world, about 200 small demonstration fuel cell power plants, rated at about 250 Kw each, are churning out electricity, mostly to gain operating experience, built by ONSI, a United Technologies/Toshiba joint venture. But other types such as molten carbonate, proton exchange membrane and solid oxide fuel cell plants are already being tested.
For transportation, the proton exchange membrane (PEM) fuel cell is the preferred type. It operates at fairly low temperatures, starts more easily and is easier to make compact enough to fit into a car, bus or truck. Germany's Daimler-Benz now DaimlerChrysler in concert with Canadian fuel cell pioneer Ballard Power Systems and recently joined by Ford, has been the acknowledged leader since the early 1990s when development began to take off. General Motors and Japan's Toyota trail closely, very closely behind. Just about all other car makers, plus many upstart developers, are racing to develop fuel cell vehicles, including three-wheelers and scooters popular in Asia.
NECAR 3, developed by Daimler-Benz, is the first-ever fuel cell powered car that uses methanol as the source fuel
Conceding that there are still lots of technical problems to solve, many corporate heavyweights believe fuel cell cars should be commercially ready around 2004-2005 at least technically. Those early models will probably be pricey: a Toyota executive has said he expects them to cost two to three times as much as today's gasoline-burners, and he does not expect them to be popular for another 30 years or so.
Costs are still a big issue indeed, less so for stationary power plants where investment outlays are beginning to approach commercial levels, particularly when aided by subsidies. But competing on the road is tough: the cost per kilowatt, or horsepower, if you prefer, of today's essentially hand-made fuel cells can be as much as 100 times that of the old reliable internal-combustion engine. Studies by GM and others predict, however, these numbers will come down to comparable levels with mass production.
In developing countries, fuel cells are likely to be tried first as low-polluting engines in urban buses. The United Nations Development Programme (UNDP) and the Global Environment Fund (GEF) are developing feasibility studies for Sao Paulo, Cairo, New Delhi, Mexico City and Beijing. Sao Paulo is furthest along, and proposals for a demonstration phase may be on the table this spring. China issued a request for proposals in early 1998, but scarcity of funds killed those prospects.
What about the fuel? Hydrogen, one of the two components of water, H2O, is by definition pollution-free particularly when produced via solar energy and electrolysis from water. When recombined 'oxidised' with the air's oxygen in a fuel cell, it returns to steam. But so far, it is hard to store on board. One proposed interim solution would be to extract hydrogen from fuels such as gasoline or methanol onboard the vehicle by a kind of micro-chemical plant. Proponents argue this makes sense because fuel infrastructures exist for most of these fuels almost everywhere but not for hydrogen. However, pure hydrogen is the environmental "gold standard," as California's recent tougher anti-pollution rules put it.
The fuel cell car engine creates electricity from hydrogen, and oxygen in the air, through an electrochemical process that forms only water and heat as by-products. The hydrogen an be stored on the vehicle or extracted through thermochemical processes from natural gas methanol, gasoline or ethanol or other hydrogen carriers.
As to costs, some experts argue that while the cost of hydrogen extracted from fossil fuels would be about twice that of North America's cheap gasoline, it would be just about offset by the fuel cell's better efficiency. Others maintain the cost of the extra "reforming" machinery both on the vehicle and at the station would be higher than for a hydrogen system, making "pure" hydrogen vehicles more attractive even now.
The bottom line is that clean cars and power plants will become affordable and feasible, but it will take a while. A cleaner environment, a more stable climate via reduced carbon dioxide in the atmosphere, lower public health costs because of less soot, smoke, unburned hydrocarbons and particulates to breathe will be the payoff.
Peter Hoffmann is editor/publisher of the international Hydrogen & Fuel Cell Letter (website: www.hfcletter.com/). A former foreign correspondent for McGraw-Hill World News/Business Week in Bonn and Milan, he is revising his 1981 book, The Forever Fuel - The Story of Hydrogen.
Fuel cell-powered cars hitting the road ahead of schedule
Hypercar is coming
Would you like a car that accelerates like a Mustang, contains no steel parts to rust away and travels 500km (313 miles) on a gallon of fuel? If so, you'll have to wait - but maybe not for very long.
Amory Lovins, the visionary Director of the Rocky Mountain Institute in Colorado, predicts that genuine first generation 'hypercars' will be on sale by 2004. And once they have arrived, he expects them to dominate the entire car market within a few years.
The hypercar concept is simple enough. Rather than pursuing incremental improvements in the design of steel cars that have remained fundamentally unchanged for 100 years, Lovins began again with the emerging technologies of the late 20th century strong, lightweight composite materials, aerodynamic profiling, high-efficiency fuel cells, hybrid electric propulsion systems and regenerative brakes.
Barely one per cent of the fuel energy released in current car engines actually moves the driver and passengers. The rest moves the car itself, is wasted in the engine and drive train, or is lost in braking, air resistance and tyres slipping against the road. Start out again with new technologies and a hypercar will weigh a third as much as an ordinary car, perform just as well and cut 90 per cent of energy losses.
Although the hypercar concept was put into the public domain in 1993, a working model has yet to be built partly a reflection of car-makers' reluctance to render obsolete their multi- billion pound investments in steel-bashing machinery. But they are now beginning to develop models that incorporate aspects of hypercar technology. And it can't be too long before one puts all those technologies together in one vehicle and Bingo!
Oliver Tickell is a freelance journalist specialising in the environment.