TURNING SUNLIGHT INTO ELECTRICITY
Chapter 5. Building the Solar/Hydrogen Economy
Lester R. Brown, Eco-Economy: Building an Economy for the Earth
(W.W. Norton & Co., NY: 2001).
After wind power, the second fastest growing
source of energysolar
cellsis
a relatively new one. In 1952, three scientists at Bell Labs in
Princeton, New Jersey, discovered that sunlight striking a silicon-based
material produced electricity. The discovery of this photovoltaic
or solar cell opened up a vast new potential for generating electricity.36
Initially very costly, solar cells could be used only for high-value
purposes such as providing the electricity to operate satellites.
Another early economical use was powering pocket calculators. Once
run on batteries, pocket calculators now typically rely on a thin
strip of silicon for power.
The next use to become economical was providing electricity in remote
sites, such as summer mountain homes in industrial countries and
villages in developing countries not yet linked to an electrical
grid. In the more remote villages, it is already more economical
to install solar cells than to build a power plant and connect the
villages by grid. By the end of 2000, about a million homes worldwide
were getting their electricity from solar cell installations. An
estimated 700,000 of these were in Third World villages.37
As the cost of solar cells continues to decline, this energy source
is becoming competitive with large, centralized power sources. For
many of the 2 billion people in the world who do not have access
to electricity, small solar cell arrays provide a shortcut, an affordable
source of electricity. In villages in the Peruvian highlands, for
example, village families spend roughly $4 a month on candles. For
just a bit more, they can have much higher quality lighting from
solar cells. In some Third World communities not serviced by a centralized
power system, local entrepreneurs are investing in solar cell generating
facilities and selling the energy to village families.38
Perhaps the most exciting technological advance has been the development
of a photovoltaic roofing material in Japan. A joint effort involving
the construction industry, the solar cell manufacturing industry,
and the Japanese government plans to have 4,600 megawatts of electrical
generating capacity in place by 2010, enough to satisfy all of the
electricity needs of a country like Estonia.39
With photovoltaic roofing material, the roof of a building becomes
the power plant. In some countries, including Germany and Japan,
buildings now have a two-way meterselling
electricity to the local utility when they have an excess and buying
it when they do not have enough.40
Newly constructed office buildings in the United States, Germany,
and Switzerland have incorporated photovoltaic materials in their
facades to generate electricity. Nothing in the appearance of these
buildings would indicate to the casual observer that their glass
walls and windows are in fact small power plants.
Growth in the sales of photovoltaic cells averaged 20 percent a
year from 1990 to 2000. Then in 2000, sales jumped by 43 percent.
Over the last decade, worldwide sales of photovoltaic cells have
increased more than sixfoldfrom
46 megawatts of capacity in 1990 to 288 megawatts in 2000. (See
Figure 5-3.)41
The big three in solar cell manufacturing are Japan, the United
States, and the European Union. In 1999, production of solar cells
in Japan alone jumped to 80 megawatts, pushing it into first place
ahead of the United States. A large share of the solar cells produced
in the United States, which reached 60 megawatts in 1999, was exported
to developing countries. Europe is currently in third place, with
40 megawatts of production in 1999, but its capacity expanded by
more than half when Royal Dutch Shell and Pilkington Glass opened
a 25-megawatt solar cell manufacturing facility in Germany.42
When BP merged with Amoco, it also acquired Solarex, the solar cell
arm of Amoco, making BP overnight the world's third-ranking manufacturer
of solar cells after Sharp and Kyocera, both of Japan. Siemens/Shell
is in fourth place. The world solar cell market is marked by intense
competition among companies and among countries. One reason leading
industrial countries have ambitious solar roof programs is to help
develop their solar cell manufacturing industries.43
Japan, Germany, and the United States all have strong programs to
support this industry. The new Shell/Pilkington manufacturing facility
in Germany was built in response to a vigorous German program to
increase the use of solar energy, particularly on rooftops. In contrast
to the Japanese, which rely on a cash subsidy to the buyers of solar
roofing systems, the German government offers a bonus price for
solar cell electricity and uses low-interest loans to encourage
investment. Germany has a 100,000 Roofs program, with a goal of
installing 300 megawatts of solar cells by 2005. The U.S. Million
Solar Roofs program was launched in 1997. Although it is an impressive
goal, government financial support is not nearly as strong as in
Japan and Germany. Italy, too, has begun to move forward on the
solar front, with a 10,000 Solar Roofs program.44
The potential in the solar arena is enormous. Aerial photographs
show that even in the notoriously cloudy climate of the British
Isles, putting solar cells on the country's existing roofs could
generate 68,000 megawatts of power on a bright day, about half of
Britain's peak power demand.45
The costs of solar cells has fallen from more than $70 per watt
of production capacity in the 1970s to less than $3.50 per watt
today. And it is expected to continue dropping, possibly falling
to only $1 per watt as technologies advance and as manufacturing
capacity expands by leaps and bounds. Research designed to improve
photovoltaic technology is under way in literally hundreds of laboratories.
Scarcely a month goes by without another advance in either photovoltaic
cell design or manufacturing technology.46
ENDNOTES:
36.
Christopher Flavin and Nicholas Lenssen, Power Surge (New York:
W.W. Norton & Company, 1994), pp. 154-55.
37. Estimate by Paul Maycock, PV Energy Systems, discussion with
Shane Ratterman, Earth Policy Institute, 15 July 2001.
38. "Power to the Poor," The Economist, 10 February 2001, pp. 21-23.
39. International Energy Agency, "Japan: Overview of Renewable Energy
Policy," www.iea.org/pubs/studies/files/renenp2/ren/25-ren.htm.
40. According to North Carolina Solar Center's Database of State
Incentives for Renewable Energy, 37 states now have some form of
net metering; see www.dcs.ncsu.edu/solar/dsire/dsire.cfm; Germany
and Japan from Paul Maycock and Steven J. Strong, in seminar at
American Solar Energy Society Annual Conference, May 2000, Madison,
WI.
41. Figure 5-3 from Paul Maycock, PV Energy Systems, discussion
with Shane Ratterman, Earth Policy Institute, 28 May 2001.
42. Christopher Flavin, "Solar Power Market Jumps," in Lester R.
Brown et al., Vital Signs 2000 (New York: W.W. Norton & Company,
2000), p. 58.
43. Maycock, op. cit. note 41.
44. Siemens Solar, "New German Government Announces 100,000 Rooftop
Photovoltaic Program," press release, www.siemenssolar.com/german_rooftop_program.html,
viewed 25 June 2001; Million Solar Roofs program from DOE, www.eren.doe.gov/millionroofs/;
Italian program in Molly O'Meara, "Solar Cells Continue Double-Digit
Growth," in Lester R. Brown et al., Vital Signs 1999 (New York:
W.W. Norton & Company, 1999), pp. 54-55; German program in Christopher
Flavin, "Solar Power Market Surges," in Worldwatch Institute, op.
cit. note 3, p. 46.
45. R. Hill, N.M. Pearsall, and P. Claiden, The Potential Generating
Capacity of PV-Clad Buildings in the UK, Vol. 1 (London: Department
of Trade and Industry, 1992).
46. O'Meara, op. cit. note 44; prices for photovoltaic modules held
steady at $3.50/watt for 2000-01, according to Christopher Flavin,
"Solar Power Market Surges," in Worldwatch Institute, op. cit. note
3, pp. 46-47.
Copyright
© 2001 Earth Policy Institute
|
|