Solar power from deserts - could it end fossil fuel dependency?

Deserts could hold the key to the world's energy problems, according to an international research and campaigning network. Vast quantities of clean, affordable energy could be generated by solar power plants in desert regions connected to an international supergrid.

Less than 1 percent of the area of the world's deserts could provide as much electricity as the world now uses. Less than 0.3 percent of the desert areas of Northern Africa and the Middle East could produce enough electricity to meet present-day demands of these regions and Europe, said Dr Gerry Wolff of the DESERTEC Foundation.

"If the politicians create the right environment for the industry, they can do things very fast. If they really put their back into it, we could get the whole thing built in 10 years," said Dr Wolff.

Germany, the Netherlands, Tunisia and Jordan have endorsed the development plans put forward by DESERTEC.

DESERTEC's proposal recommends the construction of an intercontinental supergrid capable of transmitting solar electricity across vast distances. As much as 90 percent of the world's population lives within 2,700 km of a desert and could be supplied with solar electricity from there. The initiative could also propel development in some of the world's poorest regions.

Concentrating Solar Power (CSP) is a power generation method that uses mirrors to concentrate sun light and produce heat, which in turn creates steam to drive turbines and generators. This is quite different to the better-known solar panels that spring to mind in connection with solar power. The sun's rays are not absorbed, they are reflected and bundled as if through a lens, in order to generate heat and, eventually, steam.

The shade underneath the mirrors could make infertile desert soil fit for horticulture. Photo credit: Desertec Foundation.

CSP is not a new technology. In fact, it has been tried and tested for more than 20 years in California. Its potential to generate clean, secure and affordable energy from such plants in deserts has been proven by scientists.

To ensure a steady electricity supply, one of the main problems of most renewable energy technologies, the turbines can also be driven by fossil fuels - a kind of back-up system for cloudy days or nighttimes.

"It does seem to be good technology," said Dr Michael Mason, director of the Grantham research Institute for Climate Change and the Environment, who is cautiously enthusiastic about the concept.

"There are reports that the new CSP plants in Northern Africa don't have the heat storage capacity that the plants in Spain and the United States have, but they do have fossil fuel back-up systems. That demonstrates that the investors are not yet convinced of the storage capability."

Dr Wolff thinks otherwise: "This was deliberate policy by the World Bank that helped fund the plants - to give people more confidence in the early stages."

If there are issues with the concept, nobody has raised them. "No one has questioned the science and the calculations," said Dr Wolff. "There is absolutely no doubt about it. It's not just the German Aerospace Centre that is saying it - the US Department of Energy and the American Solar Energy Association are also saying it. And they are quite careful."

Politics, not technology, appears to be the major hurdle. Combining the political and economic interests of the three regions would be no mean feat. Concerns have been raised about the effect on local wildlife and communities if large tracts of deserts were to be covered with mirrors. Rare desert species and nomadic tribes like the Berber could lose ground to energy companies.

From the European perspective it could be argued that the DESERTEC plan does not address Europe's dependency on energy imports from abroad. Just as it now relies on oil imports, it would rely on electricity imports from Northern Africa and the Middle East.

The host countries, especially those in Northern Africa, are right to ask whether an intercontinental supergrid could turn into another means of European exploitation. Other objections include security, fair pricing and maintenance costs.

A power tower in California surrounded by mirrors that reflect sunlight to the top of the tower. Photo credit: Desertec Foundation.

Dr Wolff refutes these claims and points out that the proposal incorporates recommendations on how to ensure fair deals for all involved. These include the creation of a single market, development benefits for local communities and strict environmental impact assessments.

Pavel Seifter, visiting fellow at the Centre for the Study of Global Governance at the London School of Economics, has confidence in the concept of a supergrid and the implementation solutions DESERTEC has put forward.

For example, the power plants themselves could contribute to local development. Jobs and water are often in short supply in desert regions. CSP plants could employ and train local people. Waste heat from power generation could also be used to desalinate sea water at practically no extra cost. The shade created by the mirrors could render the unproductive desert ground fertile - an opportunity for horticultural projects that could benefit local communities.

New CSP plants are currently being built in Spain, Italy, Morocco, Algeria and Egypt, indicating that the world's sunniest regions are beginning to catch on to this concept.