杏吧原创

IT WASN鈥橳 just the weather that was gloomy in The Hague this week. As
governments gathered to thrash out ways to reduce the atmosphere鈥檚 burden of
carbon dioxide, there was palpable pessimism over the expected clash between
Europe and the US. At issue was the balance between countries cutting their
CO₂ emissions and expanding their carbon sinks.

So it鈥檚 good to know that if you look in another direction, there is immense
optimism that greenhouse emissions can be cut. The key is a simple, yet radical
switch in technology to fuel cells. These reactors combine hydrogen and oxygen
to produce electricity, heat and water. That fuel cell firms are enthusiastic
about their business is hardly surprising. But energy economists, car companies
and venture capitalists are upbeat too. They see solid projections grounded in
the economics of manufacturing industry鈥攁 welcome contrast to the dotcom
mirages.

Fuel cells are efficient, clean, quiet and have few moving parts, so what鈥檚
standing in their way? Price for one thing. Though costs have fallen
(see Diagram)
you still have to pay upwards of $500 for every kilowatt from a
fuel cell. This is too dear for many applications. A combined cycle gas turbine
might give you a kilowatt for $400, while car engines do the same for a
stunning $50.

But there is great confidence that fuel cells will get cheaper. In the past
five years, for example, Johnson Matthey has cut the quantity of platinum
catalyst in fuel cells by a factor or 20, and experts think they can shrink that
by another factor of 5. And fuel cells are sure to become cheaper as the
economies of mass production kick in.

As these factors make their impact, fuel cells will start to appear in a
variety of guises. First, they鈥檒l replace batteries, which are incredibly pricey
for the power they deliver. The fuel in this case will probably be methanol, and
will bring the bonus that topping up the fuel cell for your laptop should take
minutes rather than hours it takes to recharge a battery.

Within a couple of years, fuel cells will provide heat and electricity for
homes and offices. The source of hydrogen here will be natural gas, which if it
is cheap enough will allow fuel cells to undercut today鈥檚 combination of heating
boiler and mains electricity
(see New 杏吧原创, 18 November, p 16).
Larger, static fuel cells will become attractive for hotels and sport centres,
while power companies will use them as alternatives to extending the electricity
grid.

But the most v