Research Topic 2009:

E.ON recognizes the environmental benefits of solar power and believes it will play a key role in future renewable electricity generation.

Concentrating Solar Power (CSP) technology is a renewable resource which emits virtually no CO₂ and can provide security of supply. It significantly reduces use of fossil fuels such as oil and natural gas, and increases locally-produced clean energy.

CSP is the lowest cost of the technologies available to convert solar power to electricity. When combined with thermal energy storage, CSP technology demonstrates great potential by its ability to deliver power when it is needed at a reasonable price.

This overcomes the intermittency associated with some of the other renewable power sources like wind and will ensure that CSP with storage has a place in a future energy mix.

Thermal storage in CSP systems is mainly a function of the properties of the heat transfer fluid and working temperature, although other factors such as plant size have an effect.

Three heat transfer fluids are:

• Steam used in power towers and troughs
• Mineral oil in most parabolic trough plants
• Molten nitrate salts in power towers.
  

The working temperature for steam is limited. Molten salts and oil break down at high temperatures, with molten salt and steam achieving the highest temperatures of about 565° C for nitrate salts.

Important development areas for CSP heat storage systems are the storage medium, materials and insulation of storage tanks and the integration and optimization of the overall system.

Existing CSP systems use liquids or solids to retain energy using sensible heat storage, a technique in which temperature changes can be measured or ‘sensed’. Alternatives may be latent heat storage, using phase change materials, and heat storage by means of reversible chemical reactions.

Developing CSP technology will require time to investigate scalability, economic feasibility, health and safety, and integration, taking account of temperatures, energy capacities, discharging profiles and response times.

This call aims to support research focused on innovative heat storage for CSP systems, ultimately for use in commercial-scale generating plant. Successful applications will help to identify clear routes towards better CSP implementation and exploitation.

E.ON will provide through the IRI up to 10 grants for research that will benefit the energy business worldwide. This call has been allocated a total of EUR6 million.