Solar power from Saharan sun could provide
Europe's electricity, says EU
- Huge £35bn supergrid would pool green sources
- Brown and Sarkozy back north African plan
Jul 23, 2008 - Alok Jha - The Guardian
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A concentrating solar power (CSP)
plant in Spain that uses panels to refl ect light on
to a central tower to produce electricity. Similar plants
are proposed for north Africa. Photograph:
AP |
A tiny rectangle superimposed on the vast expanse of the
Sahara captures the seductive appeal of the audacious plan
to cut Europe's carbon emissions by harnessing the fierce
power of the desert sun.
Dwarfed by any of the north African nations, it represents
an area slightly smaller than Wales but scientists claimed
yesterday it could one day generate enough solar energy
to supply all of Europe with clean electricity.
Speaking at the Euroscience Open Forum in Barcelona, Arnulf
Jaeger-Waldau of the European commission's Institute for
Energy, said it would require the capture of just 0.3% of
the light falling on the Sahara and Middle East deserts
to meet all of Europe's energy needs.
The scientists are calling for the creation of a series
of huge solar farms - producing electricity either through
photovoltaic cells, or by concentrating the sun's heat to
boil water and drive turbines - as part of a plan to share
Europe's renewable energy resources across the continent.
A new supergrid, transmitting electricity along high voltage
direct current cables would allow countries such as the
UK and Denmark ultimately to export wind energy at times
of surplus supply, as well as import from other green sources
such as geothermal power in Iceland.
Energy losses on DC lines are far lower than on the traditional
AC ones, which make transmission of energy over long distances
uneconomic.
The grid proposal, which has won political support from
both Nicholas Sarkozy and Gordon Brown, answers the perennial
criticism that renewable power will never be economic because
the weather is not sufficiently predictable. Its supporters
argue that even if the wind is not blowing hard enough in
the North Sea, it will be blowing somewhere else in Europe,
or the sun will be shining on a solar farm somewhere.
Scientists argue that harnessing the Sahara would be particularly
effective because the sunlight in this area is more intense:
solar photovoltaic (PV) panels in northern Africa could
generate up to three times the electricity compared with
similar panels in northern Europe.
Much of the cost would come in developing the public grid
networks of connecting countries in the southern Mediterranean,
which do not currently have the spare capacity to carry
the electricity that the north African solar farms could
generate. Even if high voltage cables between North Africa
and Italy would be built or the existing cable between Morocco
and Spain would be used, the infrastructure of the transfer
countries such as Italy and Spain or Greece or Turkey also
needs a major re-structuring, according to Jaeger-Waldau.
Southern Mediterranean countries including Portugal and
Spain have already invested heavily in solar energy and
Algeria has begun work on a vast combined solar and natural
gas plant which will begin producing energy in 2010. Algeria
aims to export 6,000 megawatts of solar-generated power
to Europe by 2020.
Scientists working on the project admit that it would take
many years and huge investment to generate enough solar
energy from north Africa to power Europe but envisage that
by 2050 it could produce 100 GW, more than the combined
electricity output from all sources in the UK, with an investment
of around €450bn.
Doug Parr, Greenpeace UK's chief scientist, welcomed the
proposals: "Assuming it's cost-effective, a largescale renewable
energy grid is just the kind of innovation we need if we're
going to beat climate change."
Jaeger-Waldau also believes that scaling up solar PV by
having large solar farms could help bring its cost down
for consumers. "The biggest PV system at the moment is installed
in Leipzig and the price of the installation is €3.25 per
watt," he said. "If we could realise that in the Mediterranean,
for example in southern Italy, this would correspond to
electricity prices in the range of 15 cents per kWh, something
below what the average consumer is paying."
The vision for the renewable energy grid comes as the commission's
joint research centre (JRC) published its strategic energy
technology plan, highlighting solar PV as one of eight technologies
that need to be championed for the short- to medium-term
future.
"It recognises something extraordinary - if we don't put
together resources and findings across Europe and we let
go the several sectors of energy, we will never reach these
targets," said Giovanni de Santi, director of the JRC, also
speaking in Barcelona.
The JRC plan includes fuel cells and hydrogen, clean coal,
second generation biofuels, nuclear fusion, wind, nuclear
fission and smart grids. De Santi said it was designed to
help Europe to meet its commitments to reduce overall energy
consumption by 20% by 2020, while reducing CO² emissions
by 20% in the same time and increasing to 20% the proportion
of energy generated from renewable sources.
Backstory
High voltage direct current (HVDC) transmission
lines are seen as the most efficient way to move electricity
over long distances without incurring the losses experienced
in alternating current (AC) power lines. HVDC cables can
carry more power for the same thickness of cable compared
with AC lines but are only suited to long distance transmission
as they require expensive devices to convert the electricity,
usually generated as AC, into DC. Modern HVDC cables can
keep energy losses down to around 3% per 1,000km.
HVDC can also be used to transfer electricity between different
countries that might use AC at differing frequencies. HVDC
cables can also be used to synchronise AC produced by renewable
energy sources.
· This article was amended on Thursday July 24 2008. The
scientist referred to above from the European commission's
Institute for Energy is Arnulf Jaeger-Waldau, not Jaeger-Walden.
This has been corrected
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