ABB's System 800xA drives Spanish solar power facility

Dec. 14, 2007

Zurich, Switzerland, December 14 -- Europe’s first large-scale solar energy plant--the 100 megawatt Andasol I and 2 in the Sierra Nevada of southern Spain--opens up a new era in renewable emissions-free power generation. ABB’s Extended Automation System 800xA will control this innovative new process.

Currently under construction in one of the sunniest parts of Spain--the desert-like heights of the Sierra Nevada in Andalusia--Andasol will be the largest solar energy plant in Europe, and one of the largest in the world, when completed in 2009. It will also be Europe's first parabolic trough power plant.

Andasol 1 and 2 will each generate 50 megawatts of emissions-free electricity using innovative technology that captures and concentrates sunlight in two vast solar fields of trough-shaped parabolic mirrors. The technology converts the solar radiation into heat, which is pumped to adjacent power plants where it generates electric power from steam turbines.

Parabolic trough power plants use concentrated sunlight in place of fossil fuels to generate heat and steam to drive turbines and create electricity in a conventional thermal power plant. A large field of parabolic trough mirrors track the sun and concentrate solar radiation on a collector tube installed at the focus of the mirror. Heat transfer fluid passing through the collector tube is heated to temperatures high enough to generate steam.

Both power plants will be controlled by ABB’s Extended Automation System 800xA and ABB Power Generation Portal software. The power generated at the plants will be delivered to the local grid via ABB power transformers and substation equipment.

Andasol I and 2 will produce about 350 gigawatt hours of electricity per year, enough to power 100,000 Spanish households, and displace 345,000 tons of greenhouse gas emissions a year.

Each power plant will have its own 200-hectare solar field containing 624 parabolic troughs arranged in 156 loops. The fields produce up to twice the thermal energy that can be absorbed by the plants’ steam turbines. The excess energy is stored in liquid salt tanks for up to seven hours, thereby ensuring a continuous and stable supply of electric power to the grid.

Andasol will be the second solar energy plant in the world to use parabolic troughs to capture solar radiation and generate electricity on a commercial scale. The first is the 64-MW Nevada Solar One in the United States.