Better solar technologies warm up plans to generate electricity for Europe in Africa’s deserts

27 Oct 2011 | News
At its 2nd annual conference next week, the Desertec project for the large-scale production of electricity from sunlight in the deserts of north Africa – and its export to Europe – will discuss progress to date

Swiss start-up Airlight Energy is to build the first concentrated thermal solar power (CSP) plant in Morocco, a move that will be an important test bed for the technology, which it is claimed will overcome the intermittent generating capability that is the major shortcoming of solar photovoltaics.

Airlight Energy will construct the plant for Italcementi, the world’s fifth largest cement producer, at the site of the Italian company’s cement works in Ait Baha in Morocco. The solar field will be integrated into the existing heat recovery system at the cement works to provide an additional 150 kW of electric power – around the clock - using three solar collectors and a storage unit.

The plant will be based on a prototype that Airlight Energy has built to test its technology in Ticino, Switzerland. The Italcementi contract is a major opportunity for the start-up to enter the competition for large-scale CSP deployments envisaged by Desertec, the grand project that aims to deliver as much as 15 per cent of the European Union’s electricity needs from the deserts of northern Africa through high-voltage transmission lines under the Mediterraneans Sea.

Desertec was set up two years ago with the backing of large European industrial groups including Siemens and ABB, with financial sector backers including Munich Re and Deutsche Bank. Along with wind energy, CSP is at the heart of Desertec’s vision. Next week at its second annual conference in Cairo, Desertec will report on progress to date.

Large-scale plants in sunny areas are already cost-competitive

Desertec lighted on CSP because unlike solar photovoltaics, the cost of electricity generated by CSP is already competitive with conventional forms of production, provided the plants are situated in very sunny areas like Morocco, with its 2,300 hours of sunshine each year.

It has proved difficult to integrate photovoltaic systems - based on hundreds of individual units that only generate electricity when the sun shines - into existing electrical grids. New CSP technologies like that developed by Airlight Energy promise to overcome the intermittent nature of existing solar power generation. CSP does this by allowing electricity generated during the day to be stored as heat and used to drive turbines at night.

According to Desertec, covering 3 per cent of the surface of the Sahara desert with CSP systems would generate enough electricity for the entire world. And now improvements in high-voltage direct transmission technology for the long distance transport of electricity mean it would be cost-effective to ship this power to Europe.

A place in the sun for more than one solar technology

The technology may be at hand, but despite this, Desertec is yet to make much progress on the ground. In May, the Moroccan Agency for Solar Energy signed a memorandum of understanding with the consortium, the Desertec Industrial initiative (Dii), in which it was agreed to cooperate on projects that are intended to demonstrate the feasibility of exporting electricity from Morocco to Europe.

Klaus Schmidke, head of communication at Munich-based Dii said, “The projects will test CSP technologies at a 400 MW production capacity, to be largely exported, as well as photovoltaics at a 100 MW production capacity, for local use.”

The estimated cost of Desertec is €400 billion, and the timeline somewhat slow, with the aim of completing the project by 2050.  Until then there will be a lot of competition, both at a financial and a technological level. One example is the French consortium Transgreen, set up in July 2010. Transgreen’s sponsor Alsthom has just invested $130 million in US-based BrightSource’s CSP tower technology, which is likely be the technology of choice for the French-led project.

In addition, the size of Desertec suggests there will be room for more than one technology. Abengoa, a Spanish manufacturer of parabolic trough power plants and Tessera, an American CSP manufacturer, have the leadership for now, but their positions are already threatened by other companies such as France’s Areva. So, getting its first commercial deal is an important validation of the Airlight technology and positions the Swiss start-up as a serious contender to secure Desertec contracts.

Apart from improving the collection of solar energy, Airlight has made a major improvement in the efficiency of its CSP system, by storing the energy not by heating oil or water, but heating air. According to Airlight’s chairman, Francesco Boligiani, these advantages have attracted Siemens, as the leading partner in Desertec, to further investigate Airlight’s technology. It remains to be seen if Desertec selects the Swiss technology. But with its first €2.7 million contract from Italcementi, Airlight Energy is one of the few companies that is making the promise of CSP a reality.

More about Desertec

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