Research in renewable technology development keeps on producing positive results in Spain. This time, the R & D laboratory at the company AORA-Solar has developed at the Plataforma Solar de Almería (PSA) the fifth generation of its solar receiver, which allows greater efficiency in the generation of electrical energy by heating compressed air at some 1000 ° C.
The plant, located in February 2012 at the Plataforma Solar de Almería, has been established as AORA-Solar’s R & D + i laboratory and test bench in Europe both for its new technological developments such as for the new developments from third parties cooperating with the Company. Thus it is expected that the work developed in Spain can be exported to other parts of the world.
Why is it novel
One of the features that make the technology designed by AORA Solar be innovative is that it is designed in such way that it requires less land area and less water, while generating more useful electricity and more thermal energy than other solar systems. This is possible because it uses a 100 kWe gas turbine coupled to a solar receiver capable of heating compressed air to about 1000 degrees Celsius. Solar radiation is reflected in the opening of the solar receiver using a heliostat field. The system uses hot air to operate the microturbines. “The research work that we are developing in Almería – explains Pierre René Elbaz, VP AORA-Solar – has allowed us to optimize our system’s efficiency and lower our plants components costs. We face a new generation of solar thermal plants that improve performance and ensure greater sustainability of the system. Furthermore it is allowing us to demonstrate the ability of this technology to provide clean energy to our customers without interruption. “
Compressed air instead of water
One of AORA Solar plants’ features is their low water consumption, resulting from the use of compressed air. The use of water is not necessary for the electricity generation process due to the absence of a steam cycle as in conventional solar thermal power plants. “This gives us two advantages: the first one is that it is a plant much more respectful of the environment. The second is that in locations with more sunlight, such as Andalusia, water is a scarce resource, a drawback that AORA plants have overcome, “says Pierre René Elbaz. Besides electricity, the plant also produces 170 kW of surplus thermal energy that can be used for different cogeneration applications (desalination, absorption-cooling, etc..).This ability to recover waste heat from the turbine, allows an overall plant performance exceeding 80%.
A hybrid system
Another novelty in the Almería plant is that it is hybrid. This means that not only can it operate with solar radiation, but also with any type of alternative fuel, ensuring that the system works steadily 24 hours a day, 7 days a week. “If the temperature of the compressed air flowing through the turbo-generator drops to levels lower than 950 degrees Celsius, fuel feeding enters into operation, allowing the turbine to further operate and generate electric power. Similarly, when the temperature goes up, fuel use stops, “said Pierre Elbaz. AORA Solar currently has two research and demonstration plants in operation, one, the Solar Platform in Almeria (Spain) and another in Israel. Almería plant has been co-funded by the Centre for the Development of Industrial Technology (CDTI)with Feder funds.