hotovoltaics are finally set to contribute
a meaningful amount of electricity. You do remember PV, don't you? The solar
electricity source that, during the energy crises of the 1970s, promised
to save the world from fossil fuels. These de-centralized power generators
would democratize energy, cut pollution, slow strip-mining and reduce oil
spills.
Long before we began dreading greenhouse
warming, these advantages made PV the holy grail of environmentalists. Yet
there was a major problem: PVs were expensive.
Yes, we were told, the price would
drop eventually. But eventually never seemed to arrive, and no amount of
support from enthusiastic environmentalists could give PVs a real role in
real-world energy production.
Sure, PV's made sense for satellites,
the Australian outback, and elsewhere beyond the reach of power lines. But
by 1995, all solar sources combined contributed only 0.003 percent to the
US electricity supply. Eventually, the stubborn price problem caused many
PV champions to lose interest and focus on conservation instead.
Yet behind our backs (aided by $1.5
billion in federal subsidies over the past 25 years), PV is making a big
comeback. Prices have fallen by a factor of 100 since 1972. Manufacturing
costs are still dropping and efficiencies are still rising. Some electric
utilities have even lost their fear of PV, and are talking, in their gray-suited
way, about an "appropriate mix" of energy supplies.
In other words, with little notice
from environmentalists, a real industry has arisen: Solar shingles, which
keep out rain and produce electricity, reached the market this year. So
did other thin-film solar panels. This long-heralded, cut-rate technology
avoids the need for expensive crystalline silicon.
U.S. solar power manufacturers had
record sales of $850-million in 1996, supplying 39 percent of world PV output.
Globally, PV output is growing 15 percent per year, with a doubling time
of less than five years. PV manufacturers have waiting lists of six months
or more and are frantically building capacity.
While demand is particularly heavy
in less-developed countries, where the electric infrastructure is weak or
nonexistent, one of the most promising developments is in California. Last
May, the Sacramento Municipal Utility District (SMUD) announced that it
would spend $22-million on enough equipment to generate 10 million watts
of electricity.
The largest contract in PV history
will supply only 3,000 customers during the day (which is when the utility's
demand peaks). But it should give manufacturers significant economies of
scale. So over the five years of the project, the installed prices is slated
to drop from $5 per watt in 1998 to $3 per watt by 2002.
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