FUEL CELLS

Most ways of generating electricity require that fuel be burned and the resultant heat used to drive a turbine or whatever that, in effect, converts heat energy into electrical energy. This process is variously inefficient, polluting, and (with some small generators) often offensively noisy. Fuel cell technology is different. It is highly efficient, almost totally non-polluting, and silent. The process is inherently efficient because the fuel consumed is not burned - nor are there any friction-causing moving parts. Instead, the chemical energy of the fuel is converted directly into electricity. Compared with a petrol/diesel generator, a fuel cell uses less than aquarter of the fuel to produce the same amount of power (it is about 75-80% efficient).

Whilst fuel cells use hydrogen and oxygen to generate electricity, the hydrogen that they require can be produced from a wide range of fuels - from diesel, petrol, methanol, biomass, LPG - even powdered magnesium. At present the trend is to LPG or methanol powered cells in which the conversion to hydrogen is performed internally. In the longer term however, and especially for larger systems, hydrogen is likely to be generated, distributed and sold much as LPG and auto gas is now.

Dry Cell Replacements Soon

The technology can be used to make fuel cells of virtually any required size. Large-scale units have been available for many years (but at prices that appeal primarily to the military). The race is now on however to develop affordable mass-produced fuel cell products. The initial market is likely to be small fuel cells that power portable devices that use more power than can realistically be generated or stored by conventional batteries (e.g. notebook and laptop computers, cell phones, MP3 music players etc).

This is not simply conjecture. In June 2004, Toshiba unveiled a prototype fuel cell that can run an MP3 player for about 20 hours (about 1 watt per hour) on a two cubic centimetres cartridge (about a dessertspoon full) of methanol. Commercial products are expected in 2005. Samsung has demonstrated a compact 12-watt fuel cell that powers its notebook computer. In the USA, MTI Micro Fuel cells has joined forces with Gillette (owner of Duracell batteries) to produce micro fuel cells in quantity. Meanwhile, the International Electrotechnical Commission is seeking to draw up standards that will ensure the similar compatibility that has long existed with dry cell batteries (AA, AAA etc). As the forthcoming miniature fuel cells are likely to be powered by methanol cartridges, these too are likely to be standardized. The RV Market The fuel cell product market of obvious interest to campers, caravan and motorhome owners, is that of 650-3500 watt replacements for generators and, in some cases, solar power. Whilst such product development is in hand, it is currently accompanied by misinformation and exaggeration hype the like of which is seldom encountered outside an election campaign.

Hyped by non-technical feature writers and web-site commentators, totally absurd claims are being made for product availability and (particularly) energy efficiency.That, typically quoted, represents up to ten times the chemical energy of the fuel consumed. This is the equivalent of perpetual motion with a power take-off. Right now, most US companies in this field are venture capital start-ups with much of the development seemingly aimed at parting ingenuous investors from their cash. Some are more serious, but few are even planning field trials of fuel cell prototypes before 2006 - let alone producing actual product. Fortunately European and Japanese companies seem more interested in turning out actual products. This is probably because most have backgrounds in producing heating/energy products. Nippon Oil, Osaka Gas and Sanyo are aiming to have 1000 watt units available for about US$4,000 in 2005. Nippon has been running a Japan-wide trial of one hundred 1 kW, LPG-powered units since April 2003. The European company, Hymer (an RV maker) is already marketing a 25-watt fuel cell (with a large fuel tank) that can replace batteries in many applications. A more powerful 50-watt unit is expected soon.

Under $1,000 Barrier

The problem does not lie in providing 1,000 or so watts in a small packet. That capability has existed for at least ten years. Rather, it is in producing commercial quantities of fuel cells that cost less than $1 per generated watt. The reality is likely to be a 100 amp/hour battery-sized box weighing 5-10 kg, and producing about 1,000 watts for about 12 hours whilst consuming about 1 kg of LPG, or the chemical energy equivalent of other fossil fuels. The price will be about $999 simply because there’s no large-scale market otherwise. Eventually prices are expected to fall to a tenth or so of that. When? It could be 2005, but 2006 is now looking more likely. But when (not if) that happens, conventional gensets will be driven off the face of this planet. And not a moment too soon!

Long-Term Change

On a grander scale, fuel cell technology has the very long term potential to turn the world’s energy economy from petroleum-based to hydrogen-based. This will require massive changes but the benefits are staggering - not the least because hydrogen can be produced via renewable resources and also readily stored. Again this is not simply conjecture. According to a research report (McCormick 2003) General Motors has already looked at the feasibility of a US-wide infrastructure that will place a hydrogen pump within about 3 km of 70% of the US population, plus every 40 km on almost all interstate roads. The cost is estimated at US$10-US$15 billion. Not only may we see highly-efficient non-polluting transport, but we may also see affordable decentralised electrical power generation systems that could massively change the lifestyle of presently underdeveloped countries.

But right now, the earliest affordable products are likely to be as above! Please note that all my published writing, including all of the above, is copyright Caravan & Motorhome Books, H. My books are available directly from the CMCA in Australia, and the NZMCA in New Zealand.
Collyn Rivers, W8054