麻豆传媒

LONDON鈥檚 fabulously successful Tate Modern art gallery has wowed the public.
Now it seems that the gallery, housed in the disused Bankside power station, has
captured the industrial zeitgeist, too. Power stations, the behemoths of the
industrial age, could be on the way out.

As politicians in the Hague this week thrash out ways of limiting the amount
of greenhouse gases in the atmosphere, industry strategists are forecasting the
demise of giant, centralised generating stations. The environmental benefits
could be immense.

The people that spread thousand-megawatt power plants across the planet now
see the future in small generators, each little more than a millionth as
powerful, in basements and backyards round the world. One of the biggest
enthusiasts is Karl Yeager, who heads the US industry-funded Electric Power
Research Institute in Palo Alto, California. By 2050 he thinks that most of our
electricity will come from millions of microturbines, solar panels and, most
importantly, hydrogen-powered fuel cells.

鈥淲ithin five years I鈥檒l be able to go down to Wal-Mart and pick a
microgenerator off the shelf to power my house,鈥� says Yeager. 鈥淚 will take it
home and connect it to the gas pipe. It will generate power as well as heating
my house and producing hot water. And it will be much cheaper than using the
power grid.鈥�

Existing national power grids won鈥檛 disappear. But Yeager believes they will
operate more like the Internet, as part of a complex web through which people
will supply electricity as well as downloading it. And countries that don鈥檛 have
large-scale power networks will cease to need them. The result will be greater
efficiency, less pollution and an end to power cuts.

Dan Rastler, a researcher at the EPRI, thinks his boss is being conservative.
He notes that natural-gas fuelled microgenerators for the home are being tested
this year. 鈥淚 anticipate some market penetration as early as 2002,鈥� he says. The
cost of a 5-kilowatt kit鈥攚hich would provide more than enough power for
most houses鈥攚ill be about $2500. Some will buy bigger and sell to
the grid; others will buy smaller and top up from the grid when they need
to.

Seth Dunn of the Washington environmental think tank the Worldwatch Institute
shares Yeager鈥檚 vision. In a new pamphlet, Micropower: The next electrical
era, he writes: 鈥淎n electricity grid with many small generators is
inherently more stable than a grid serviced by only a few large plants.鈥� And it
will be the perfect way to introduce renewable energy. It will also, as it
happens, be much like the world Thomas Edison envisaged when he opened his first
power plant in downtown New York in the 1880s and forecast that soon every
community would have one.

Two technological developments are driving the revolution. First, the new
generation of clean and cheap electricity generators small enough for domestic
use. Second, the emergence in recent years of 鈥渋ntelligent鈥� grids able to
collect as well as distribute electricity at every node. These will allow people
to sell their surplus electricity or even trade regularly in electricity.

Besides natural gas-powered electricity, the world is on the verge of
adopting cheap fuel cells, electrochemical devices that combine hydrogen and
oxygen to produce electricity and water. A big thrust for this research comes
from car manufacturers looking for a more efficient, less polluting alternative
to the internal combustion engine.

Yeager sees the involvement of the car industry as a big plus. Its
manufacturing capacity dwarfs that of the electricity generators. Every two
years it makes internal combustion engines with a combined power capacity equal
to all the world鈥檚 electricity generating stations. Replace those car engines
with fuel cells and it takes no great leap of the imagination to envisage
millions of similar cells being manufactured to power homes. The fuel cells will
run on hydrogen, and Rastler says he sees homes receiving piped supplies.

It is even possible that cars and homes might share the same power source.
鈥淲hen you get home at night you will be able to drive into the garage and plug
the fuel cell into the home circuit to power the microwave and the TV,鈥�
forecasts Yeager. 鈥淭here is no reason why the auto shouldn鈥檛 be a power source
for your home when you are not driving it. In fact, vehicles could provide an
extensive power generation and storage network.鈥� A million fuel-cell vehicles
plugged into the grid could generate up to a tenth of US electricity needs.

Hydrogen will have to be manufactured, of course, and for this there are two
routes. One involves splitting water molecules using electricity. It requires
much more electricity than you鈥檒l get back from the fuel cells, so the gain only
arises if that electricity is made using non-polluting sources, such as solar,
wind or hydroelectric power. The alternative is extracting hydrogen from a
hydrocarbon such as oil, methanol or natural gas. Either way there can be real
environmental gains in terms of carbon emissions into the atmosphere.

On top of that, a big spur is the growing problem of power cuts. The ageing
and underfunded grid system in the US is creaking. Dunn estimates that power
cuts cost the country as much as $80 billion a year. Losses of power
lasting as little as a few hundredths of a second can cause mayhem, says Yeager,
鈥渃rashing servers, computers, life-support machines and automated
别辩耻颈辫尘别苍迟鈥�.

鈥淚n the digital economy you need ultra-reliable power,鈥� says Dunn. 鈥淚t鈥檚 got
to be better than 99.9999 per cent. Conventional utilities just cannot do that.鈥�
That鈥檚 why, says Yeager, California鈥檚 computer companies are all developing
their own power systems. No wonder share prices for the pioneers of micropower
and fuel cells surged earlier this year in the US.

Countries with national power grids will continue to find them useful as
devolved power networks. But places that don鈥檛 have extensive grids鈥攍ike
much of the developing world鈥攕houldn鈥檛 bother building them. Currently,
1.8 billion people, almost a third of humanity, don鈥檛 have access to any more
electricity than they can get from a car battery. Rather than copying
20th-century technology鈥攁s many countries are often expensively and
inefficiently attempting to do鈥攖heir governments should 鈥渓eapfrog to the
higher efficiencies of the digital age鈥�, says Yeager. Local networks running on
solar cells will provide all the electricity that most consumers need, says
Dunn.

But the biggest gain for the world could be in curtailing global warming.
EPRI researcher Steve Gehl anticipates that by 2050 disconnected communities
will gain access to basic electric power of the kind available to Americans in
the 1920s. Taken together with trends in the rich countries, that would require
a global generating capacity totalling three times today鈥檚. Doing the job the
20th-century way would mean building a new 1000-megawatt power plant somewhere
in the world every two days for the next 50 years. And that would send carbon
dioxide emissions soaring way out of control.

The world鈥檚 governments know that they need to do vastly better than the
Kyoto agreement if they are to prevent CO₂ concentrations in the
atmosphere exceeding the safety ceiling of 550 parts per million being suggested
by the world鈥檚 scientists. That鈥檚 twice pre-industrial levels and 50 per cent
above today鈥檚. It is not consistent with a business-as-usual electricity
industry.

Yeager says it is possible to electrify the poor world while staying below
the 550 ppm ceiling. But it will require drastically cutting the volume of
CO₂ emissions for every unit of electricity generated. He says that by
2050 we must cut average emissions to a fifth of those from a modern, efficient
coal-burning power station and to less than half those from natural-gas plants.
And to remain below the ceiling till the end of the century will require moving
to an essentially carbon-free energy economy.

Some people don鈥檛 believe the job can be done without massive disruption to
the world economy. Yeager and Dunn both say it can be鈥攁nd the first step
is to overthrow the tyranny of the multi-megawatt power station.