Using the Environmental Benefits of Solar Power with Heat Storage for Concentrating Solar Power (CSP)
E.ON recognizes the environmental benefits of solar power and believes it will play a key role in future renewable electricity generation.
Therefore the 2010 call was aimed at supporting research focused on innovative heat storage for CSP systems, ultimately for use in commercial-scale generating plants. The winning projects will help to identify clear routes towards better CSP implementation and exploitation.
A total of five research projects were awarded with the E.ON Research Award in September 2010.
INNOLAT-CSP: Development of an Innovative Latent Heat Storage for Concentrating Solar Thermal Power Using Direct Steam Generation and Other Transfer Fluids
Fraunhofer Institute for Solar Energy Systems (Germany)
A novel concept in thermal energy storage forms this project which physically separates the heat transfer process and the storage capacity. This approach uses screw heat exchangers - rotating, hollow tubes - whose threads move phase change material (PCM) between two tanks. Steam or hot transfer fluids from concentrating solar power (CSP) plant flow through the tubes, storing latent and sensible heat in the PCM which becomes molten. Stored energy is released by reversing the screws as another fluid removes the heat, re-solidifying the PCM.
Innovative Latent Thermal Energy Storage System for Concentrating Solar Power Plants
The University of South Florida, Clean Energy Research Center (US) and the Madrid Institute for Advanced Studies IMDEA Energy (Spain)
A new generation of phase change materials (PCMs) is to be developed to boost the performance of thermal energy stores linked to concentrating solar power (CSP) plant. In this concept, PCM pellets are retained inside special coatings and packed in tanks. Hot fluid from the CSP plant fills the tank, passing latent heat to the PCM which liquefies. To raise steam for electricity generation, a cooler fluid is circulated through the tank causing the PCM to re-solidify and discharge heat for transfer to the power plant.
High Energy Density Storage for Thermal-solar Advanced Renewable Technologies - HEDSTART
University of Nottingham (UK)
This project seeks a breakthrough in thermal energy storage by developing a reversible chemical technology which can absorb and release heat captured from the sun by concentrating solar power (CSP) plant. A magnesium hydride compound absorbs the CSP heat, breaking down into hydrogen and magnesium. When electricity generation is required, these elements are recombined, releasing the solar heat to raise steam to power turbines. A one-tenth scale prototype of this thermal energy store concept will be built to demonstrate the technology.
Development of the CellFlux Storage System for Sensible Heat
Deutsches Zentrum für Luft- und Raumfahrt e.V. (Germany)
Research into innovative energy cells will focus on storing solar power as high temperature heat in solid materials including rock and concrete. The CellFlux module retains concentrating solar power (CSP) thermal energy as sensible heat in a two-stage process. Heat transferred from CSP plant via fluids passes through heat exchangers into a closed air loop and then the storage material. Reversing the process releases energy for electricity generation. Tests will feature a 500kWh pilot cell which can be scaled up for utility-sized storage.
Metal Hydride Heat Storage System for Continuous Solar Power Generation
Fraunhofer Institute IFAM and Zentrum für Brennstoffzellen Technik GmbH (Germany)
An important pioneering step in this project is the aim of using nano-structured hydride-carbon composites in heat storage for the first time. The addition of carbon to metal hydrides enhances a two-way chemical conversion process which captures concentrating solar power (CSP) thermal energy and releases the heat later for electricity generation. This system features two storage tanks containing the composite material. Hydrogen flows between the tanks, absorbing or releasing heat energy as required via the chemical reaction with the composite.
