Recent interest from a number of German companies has stimulated interest in the use of the Saharan Desert to supply Europe's, and indeed potentially the world's, energy needs. The potential rewards could be considerable if all of Europe's energy needs could be met in a clean and cost effective way. The more realistic, though certainly not insignificant goal, appears to be to set at providing 15 percent of Europe's energy needs. Currently the costs of installing the technology are likely to prove prohibitive. We will have to wait until 31 October and the signing of a Memorandum of Understanding by the companies interested, to see how this particular hurdle will be overcome.
Solar in the sand
Given its obvious qualities, the Saharan desert has often been spoken of as a potential future site for large-scale solar energy development. It has been suggested that a considerable amount, if not all, of Europe's energy needs could be met through such a development. Indeed, for years an international network of scientists and engineers, collaborating under the name Desertec, has promoted this idea throughout Europe, Africa and the Middle-East. However, the plan has started to gain real momentum recently and, on 13 July, twelve German companies signed a Memorandum of Understanding to establish the Desertec Industrial Initiative by 31 October 2009. Support has also come from Nicolas Sarkozy, Angela Merkel and Gordon Brown. The plan essentially involves:
- placing a number of Concentrating Solar-Thermal Power (CSP) plants throughout the Saharan desert; and
- linking this into a European-wide 'super-grid' via High-Voltage Direct Current (HVDC) transmission lines across the Mediterranean.
This article looks further into this technology and analyses whether it is more than just a pipe dream.
A network of CSP plants throughout the Sahara?
Although there is some consideration of using Photovoltaic panels generally, CSP is seen as the technology appropriate for the Sahara. CSP uses mirrors to concentrate sunlight and create heat. The resultant heat is then used to drive turbines and generators, just like in a conventional power station. Heat can also be stored in melted salts so that electricity generation may continue at night or on cloudy days. CSP plants are up and running in the American west and in Seville. New plants are under construction in Morocco, Algeria and the United Arab Emirates.
Desert-based CSP plants have the added advantage of creating fresh water through the desalination of sea water simply using waste heat. This can be used for crop cultivation and land irrigation, a further benefit of placing this technology in the Sahara. This will be a gain for Africa beyond just the long-term investment that such a project promises.
Further benefits lie in the ability to plan, design and build CSP plants fairly quickly, in comparison to the drawn out process for conventional power plants. The lead-in time for building a CSP plant is about one year and the building time is about three years.
Connecting into Europe
Using HVDC cables, it is feasible and cost-effective to transmit electricity for more than 3,000 km. With modern HVDC only about 3 percent of power is lost for each 1,000 km In order to deliver CSP power into Europe, clearly long distance cabling to transfer it from Africa is needed. Using HVDC cables, it is feasible and cost-effective to transmit electricity for more than 3,000 km. With modern HVDC only about 3 percent of power is lost for each 1,000 km. That means, for instance, that solar electricity could be imported from North Africa to London with a loss of power of only about 10 percent.
Studies by the German Aerospace Centre (DLR) have estimated that the cost of installing the necessary HVDC cabling (20 transmission lines of 5 GW each) would be approximately €45bn. The approximate cost of two 5 GW transmission lines between North Africa and the UK is about €5 billion. Whilst expensive, this would be spread over a number of years and be spread between a number of countries. The EU has already indicated its willingness to fund the project by at least €1 billion.
More than just a great idea?
This idea has been around for a number of years and whilst Desertec is quite an established charitable foundation, it currently lacks the financial and practical resources to make the scheme viable.
The recent public interest from established German companies may change this situation. A number of companies, led by Munich Re (the insurance giant), met in Munich to confirm their interest. Other companies involved include: Siemens; Deutsche Bank; and the energy companies RWE and E.ON. Although interest is at early stages, the signature of a Memorandum of Understanding, marks a positive step towards Saharan solar development.
Whilst the technology is certainly there and in theory this sounds like a fantastic answer to all of Europe's energy needs and climate change goals, there are a number of hurdles and potential pitfalls which will need to be overcome. Among them are:
- the potential costs – with €45bn just to connect into Europe, this will be a costly project. Compounding the issue, the current credit market and cheap price of other non-renewable energy sources means there are serious doubts over the scheme's economic viability.
- political concerns – North African countries are not renowned for their political stability and problems may arise if it is felt that Europe is 'stealing' their energy for its benefit.
- practical concerns – installing a European gird of HVDC cables will be both costly and difficult. Furthermore the CSP technology relies upon a ready supply of water; not something the Sahara is notorious for having in abundance.