Abengoa and E.ON team up to build two 50 MW CSP in Spain

Both plants Helioenergy 1 & 2, already under construction and will require a total investment of around 550 million Euros. Abengoa Solar and E.ON Climate & Renewables have formed a partnership that will see them jointly own and operate two 50MW Concentrating Solar Power (CSP) plants. The plants which are already under construction are located in Ecija (Seville), Southern Spain, one of the best areas in Europe in terms of solar radiation.

The 50:50 partnership is aimed to invest a around of 550 million Euros into the two plants which will start operation in 2011 and 2012, respectively. The solar facilities will produce enough power to supply 52,000 homes and avoid the emission equivalent to 63,000 tonnes of CO2.

The participation of E.ON in the projects is however still subject to the EU–Commission approval under merger control. Santiago Seage, CEO of Abengoa Solar, explained: "Having E.ON on as a partner in these projects will allow us to continue growing at the speed we want and to improve our capabilities in areas where E.ON has extensive experience".

Frank Mastiaux, CEO of E.ON Climate & Renewables said: “Solar Power will be the next strong pillar in E.ON’s renewables portfolio. Our entry into CSP complements our recent moves into the photovoltaic business and we will now stand on two feet in solar in the future. I am also delighted to be working with Abengoa. We have found an experienced partner with whom we want to drive CSP to new levels of performance”.

The President of E.ON España, Miguel Antoñanzas, pointed out: “With this partnership for high quality projects E.ON continues its commitment to enhance its portfolio of 3.700MW of generation capacity in the Iberian Peninsula, of which over 1.100 MW are already from renewables sources”.

The plants in Ecija will utilize Parabolic Trough* technology, a solution developed in the 1980s that Abengoa Solar has in recent years tested and enhanced at the Solúcar Platform plants in Sanlúcar la Mayor, Seville.

E.ON is investing 8 billions of Euros in wind energy and renewable generation and climate protection projects between 2007-2011, and will play a leading role in the development of the renewables industry worldwide. E.ON currently has over 2.8GW of renewable capacity in operation which makes the company a leading global renewable energy player, wind power and solar energy.

Both companies are founding members of the Desertec Industrial Initiative to develop secure renewable energy production in the desert regions of the Middle East and Northern Africa.

Concentrating the Sun’s Energy

A concentrated solar power (CSP) plant works much like any thermal power plant. The difference is that it uses solar energy to produce steam to drive a turbine and generator. A CSP plant needs the right location: one that has lots of open space (for putting up mirrors) and lots of sun (like Southern Europe and the arid regions of Northern Africa and North America).

In Europe, plans for commercial CSP plants are focusing mostly on sites in Spain, which offers both solar intensity and the necessary infrastructure. CSP plants need a nearby source of water (for the steam turbine) and a nearby transmission line (to move the power to where it will be consumed).

Parabolic-trough power plants

Parabolic troughs reflect sunlight onto a tube, called an absorber, which is filled with a liquid. The concentrated sunlight produces enough heat to bring the liquid to a boil, creating steam which drives a turbine. Parabolic troughs can be mounted in rows several hundred meters long. Some of the heat produced in the steam-making process is stored so that the plant can run for up to six hours without sunlight. The world’s largest research center for high-temperature solar technology, the Plataforma Solar de Almeria in Spain, has been developing this technology since 1981. Nine parabolic-trough power plants with an aggregate generating capacity of about 350 megawatts are in operation in the United States. Their energy-conversion efficiency is roughly 14 percent.

Fresnel collectors

Fresnel collectors operate according to the same principle but concentrate sunlight using flat mirrors instead of parabolic mirrors. The advantage of this system is that it incorporates many standardized, competitively priced, and easily sourced components. E.ON is involved in research projects in this technology, as well.

Solar-tower power plants

Solar-tower power plants use hundreds of mirrors (called heliostats) that track the sun and concentrate its light onto an absorber at the top of the tower. The concentrated sunlight can generate temperatures of up to 1,000 degrees Centigrade (1,832 degrees Fahrenheit). This heat is used to create steam to drive a turbine. Heliostats represent about half the construction costs of such facilities, the largest of which is a 10-megawatt facility in California. Scientists and technicians are working to improve heliostats’ optical performance and to make them last longer. The trend is towards larger heliostats with a surface area of up to 200 square meters (2,150 square feet).

Dish Stirling units

Dish Stirling units use a parabolic dish that tracks the sun and concentrates its light onto a collector that heats an absorber (helium or hydrogen) that drives a Stirling engine. A generator transforms the engine’s rotational energy into electric energy. Dish Stirling units are relatively small and are thus suitable in micropower applications. Prototypes with a dish diameter of 8 to 10 meters (26 to 32 feet) have a generating capacity of up to 50 kilowatts.

www.eon.com