E.On has come to a milestone in its solar thermal energy business with the commissioning of a 50 MW concentrating solar power (CSP) plant in Spain.

The German utility and its Spanish partner Abengoa have brought online Helioenergy 1, the first of two CSP plants that they are building near Seville. Helioenergy 2 is due to start commercial operations later this year.

The Helioenergy plants use parabolic trough technology of the type already used in other concentrating solar power (CSP) plants such as the Solucar platform in Spain. Helioenergy 1 began commercial operations on 1 September, 2011.

The two CSP plants will together cover an area of 220 hectares and consist of 121 000 mirrors that concentrate sunlight and generate steam at temperatures of 400°C.

E.On bought into the Helioenergy project in late 2009 in a bid to expand into the CSP sector.