The goal of solar research at DLR is the development of environment and climate-friendly energy system that convert solar radiation into usable energy. The focus lies on cost reduction and further development of components and systems for solar thermal power plants.

This especially includes the work on components for parabolic and tower plants in conjunction with DLR's own experimental work - new measuring and qualification technologies and simulation tools. The research area also includes the development of new fields of application for solar technologies.

Of growing importance is solar-chemical process technology which is expected to be implemented by industry in the medium term. In addition to research activities in DLR's Cologne and Stuttgart establishments, DLR maintains a permanent team at Spain's Plataforma Solar de Almería (PSA), especially for testing and qualification of components and systems.

Due to the unique combination (within Europe) of complex facilities and excellent scientific expertise in solar research the high third-party financial share of over 50 percent can be achieved. The solar research area is divided into five research topics:

Solar chemical processes

Applications of solar radiation in chemical engineering and the production of fuel are being tested and evaluated. The main focus lies on the thermo-chemical production of the secondary energy source hydrogen. Work also includes processes for the treatment of production residues, for recycling of valuable materials, for solar photochemical conversion, and refining of chemicals, and for cleaning of air and water. Experimental results are supplemented by cost calculations and thus provide the basis for assessing the applicability of the tested methods on an industrial scale.

Thermal energy storage

Low-cost thermal energy storage systems for solar power plants are being developed and qualified. The importance of energy storage for solar thermal power plants was confirmed by recent developments in the field of renewable energies and after extensive analysis of new hybrid solar-power plant processes. Computer models of a single year's operating history have shown that the efficiency of solar power generation increases with the application of thermal storage.

Qualification

Parabolic systems both for large-scale power generation and the provision of decentralised process heat are further developed and demonstrated by optimisation of individual components and their interaction. Measuring systems for installation and maintenance are qualified for the start of the commercial use of these systems. This way the long-term profitability of solar arrays can be assessed and increased. These measurement systems are also used in other fields of concentrating systems (such as concentrating photovoltaics). Technical standards are set up for the planning, construction and operation of solar power plants and for the qualification of components.

Application development

Next-generation power plants using direct solar steam in parabolic troughs will be tested at the Plataforma Solar de Almeria on a large scale, after the controllability of this technique could be demonstrated in a first stage. In particular, the development and qualification of adapted components to increase temperatures in the collectors and the development and demonstration of improved integration concepts, operating strategies and control algorithms are emphasised. The identified cost reduction potential compared to the present technology with oil circulation is about 15 percent. The realisation of a 5 MWe demonstration plant is being prepared.

High-temperature solar systems

The use of closed high-temperature receivers in tower technology (to feed in solar energy into highly-efficient combined cycle power plants) is being developed and demonstrated. These systems, with an overall solar efficiency of around 30 percent, represent the current technical configurations with the maximum achievable efficiency and thus open up a considerable cost reductions potential.