Solar superpower: Should Europe run on Sahara sun?
Monday, October 26, 2009
EVERY two weeks, the sun pours more energy onto the surface of our
planet than we use from all sources in an entire year. It is an
inexhaustible powerhouse that has remained largely untapped for
human energy needs. That may soon change in a big way. If a
consortium of German companies has its way, construction of the
biggest solar project ever devised could soon begin in the Sahara
desert. When completed, it would harvest energy from the sun shining
over Africa and transform it into clean, green electricity for
delivery to European homes and businesses. Prospects for the project,
called Desertec, have blossomed over the past year, and this month
20 major German corporations are expected to announce the formation
of a consortium that will provide the €400 billion needed to build a
raft of solar thermal power plants in north Africa. They include
energy utilities giants E.ON and RWE, the engineering firm Siemens,
the finance house Deutsche Bank and the insurance company Munich Re.
The current plan, outlined by the German Aerospace Centre (DLR) in a
report to the federal government, envisages that the project will
meet 15 per cent of Europe's electricity needs by 2050 , with a peak
output of 100 gigawatts - roughly equivalent to 100 coal-fired power
stations. Preliminary designs in the German report show electricity
reaching Europe via 20 high-voltage direct-current power lines,
which will keep transmission losses below 10 cent ( New Scientist ,
14 March, p 42). Trans- Mediterranean links will cross from Morocco
to Spain across the Strait of Gibraltar; from Algeria to France via
the Balearic islands; from Tunisia to Italy; from Libya to Greece;
and from Egypt to Turkey via Cyprus. It is claimed that the project
could meet 15 cent of Europe's electricity needs by 2050 Desertec
would take its place in a wider European supergrid that conveys power
generated from wind turbines in the North Sea, hydroelectric dams in
Scandinavia, hot rocks in Iceland and biofuels in eastern Europe.
Adding solar thermal capacity would help ensure a steady supply of
green electricity. But is this really the best use of such a colossal
amount of money? Critics are lining up to point out the project's
shortcomings. They say it could make Europe's energy supply a hostage
to politically unstable countries; that Europe should not be
exploiting Africa in this way; that it is a poor investment compared
to covering Europe's roofs with photovoltaic (PV) solar panels; and
that, while deserts have plenty of sun, they lack another less obvious
but equally indispensable resource for a solar thermal power plant -
water. Is Desertec really the model of future power generation, as
its promoters would have us believe, or is it politically
misconceived and a monumental waste of money?