CONCENTRATING SOLAR thermal POWER
"CSP may do for fossil fuels what DVD did for VHS" - Chris Mason
quantities of energy fall as sunlight on the world’s sunny deserts and
‘concentrating solar thermal power’ (CSTP) is a proven technology for tapping in to it (see, for example, the website of the US Government's Department of Energy
at www.eere.energy.gov/solar/csp.html). This is not some futuristic
possibility like fusion nuclear power. CSTP is a relatively simple, mature and practical
technology that, with the right political and financial impetus, can be brought
into play very soon.
CSTP comes in four main variants:
On a separate page, there is a brief explanation of how the parabolic trough version of CSP works.
In CSTP plants, the heat can be stored in melted salts (eg nitrates of
sodium or potassium), and gas or biofuels may be used as a backup source of heat, so that electricity generation
may continue at night or on cloudy days (see below).
Systems like these can be installed in large
numbers as 'farms' in deserts and other sunny areas. With economies of scale, concentrating
solar power is likely to be very competitive
on cost (see How much will it cost?). There is a nice fit between wind power in northern Europe,
which is greatest in the winter, and solar or wind power
from North Africa and the Middle East, which is greatest in the summer.
A report from the German Aerospace Centre shows how, even allowing for increases in demand, a combination of CSTP with other technologies
can enable Europe to cut CO2 emissions from electricity generation by
70% by the year 2050, and phase out nuclear power at the same time. This
'TRANS-CSP' report (and the associated AQUA-CSP and MED-CSP reports) can be downloaded via links from www.trec-uk.org.uk/reports.htm.
Every year, each square kilometre of desert receives solar energy equivalent to 1.5
million barrels of oil. Multiplying by the area of deserts world-wide, this is several hundred times the entire current energy consumption of the world.
Using CSP, less than 1% of the world's deserts could generate as much electricity as the world is now using. It has been calculated that 90% of the world's population lives within 2700 km of a desert and could be supplied with solar electricity from there.
The cost of collecting solar thermal energy equivalent
to one barrel of oil is about US$65 right now and it is likely to come down to around US$26 in future.
New CSTP plants are now being planned, built or are up and running in many places around the world. The ones we know about can be seen on Google Earth, with links back to our News page.
Desertec power is clean, safe, plentiful, inexhaustible, globally distributed, technologically proven, quick to build, dispatchable (available on demand), not dependent on scarce materials or dwindling supplies of fuels, with a good EROEI,note1 and likely to become one of the cheapest sources of electricity.note2 Few other sources of power have so many positive features.
note1 “Energy Return on Energy Invested.” The energy payback time for CSTP plants is about 6 months.
note2 The TRANS-CSP report from the German Aerospace Centre (DLR) calculates that CSTP in desert regions is likely to become one of the cheapest sources of electricity throughout Europe, including the cost of transmission.
It is feasible and economic to transmit solar electricity to the whole of Europe,
the Middle East and North Africa using modern high-voltage DC (HVDC)
transmission lines. Solar power may also be transported as hydrogen.
Solar heat can be stored so that electricity generation may continue through
the night and on cloudy days.
CSTP electricity is likely to become one of the cheapest sources of
electricity, including the cost of transmitting it over long distances.
At least 90% of the world's population may be supplied with clean electricity from CSP plants in deserts around the world. There is great potential for cutting worldwide CO2 emissions from electricity generation.
CSP can provide greater security of supply than our current main sources
CSTP bonuses (click for more
CSTP can yield much more than plentiful, inexhaustible,
and secure supplies of pollution-free electricity. A major attraction of these
benefits is that, unlike money derived from oil, most of them
are of a kind that will be a direct benefit for local people and cannot easily
be hijacked by others.
CSP can, in principle, provide the large amounts of energy
needed to produce things like aluminium, steel, cement, or synthetic fuels.
How CSTP works (click for more
Click the title for a brief explanation of how CSTP works, as mentioned above.
CSTP works best in sunny deserts where there is not normally much water but there are ways of minimising the use of water that is normally required for steam generation, for cooling and for cleaning solar mirrors.
Given plentiful supplies of clean clean solar power, there is scope for replacing dirty sources of energy in transport by rail and road, in the use of synthetic fuels, and in space heating for buildings.
This section provides brief answers to some other questions that are asked about CSP, such as how CSP plants cope with sandstorms, the materials needed to build CSP plants, their environmental impact, and more.
the heading for links to leaflets, a slide show, a display on Google Earth showing CSP plants around the world, and other information.
Last updated: 2012-06-04