A DLR scientist uses a rotating shadowband irradiometer to measure the direct solar radiation.
DLR (CC-BY 3.0).
Michael Geyer was a DLR researcher for several years at the Plataforma Solar research centre in the Spanish province of Almería.
How well does a solar mirror reflect sunlight? Among other things, the test methods developed at DLR are used to examine mirrors from a variety of manufacturers.
The test facility for the hydrogen tank at the DLR Institute of Engineering Thermodynamics in Stuttgart.
Novel receiver being tested with high-performance radiators at the DLR solar furnace in Cologne.
Researchers at the DLR Institute of Solar Research test the receiver performance at the QUARZ Center in Cologne, investigating the percentage of sunlight that the tubes convert into heat . The tests are carried in the ElliRec test stand.
Proton Exchange Membrane (PEM) electrolysers can go from start-up to full load operation within minutes and thus adapt to the fluctuating supply of wind and solar power.
In the joint project 'Li-EcoSafe', researchers at the DLR Institute of Technical Thermodynamics, together with their partners, are developing and testing lithium-ion batteries.
Less than a year after its construction began, the engineers from DLR and its partners were ready to perform gas turbine combustion chamber testing.
"The expansion of facilities for flight propulsion and power plant research continues at DLR. In April 2013, two facilities were inaugurated – a hydrogen supply system and a modern high pressure compressor that will support the development of new, more economical gas turbines for aviation and energy technology. There is currently no comparable test centre anywhere in the world with such outstanding possibilities as we and our customers now have here in North Rhine-Westphalia," says Reinhard Mönig, Head of the DLR Institute of Propulsion Technology.
In cooperation with the Dutch company MTT, researchers at DLR are investigating micro gas turbines for home users.
Rotor blade trailing edges that can change their shape and flaps that divert wind when required – very large rotor blades equipped with such mechanisms can systematically correct gusts and reduce performance fluctuations. Local flow will be influenced more accurately and quickly through movable slats, trailing edges and other systems.
Receiver of the solar tower at the Plataforma Solar de Almería test site in southern Spain. Here, DLR tests new developments in solar thermal power plants. Some 35 German companies and research institutions have published a joint position paper on the market opportunities for solar thermal power plants and concentrating solar power. The newly established network with the name ‘Deutsche CSP’ will combine the strengths and interests of German companies and increase their chances in the international market. Through joint research and development, the network aims to increase the efficiency of the technology and reduce the generation cost.
The German Aerospace Center (DLR) has developed, together with the Fraunhofer Institute for Chemical Technology, a method by which the processes in the redox flow battery can be made visible. This globally unique measurement technology provides researchers with important data for making such a battery less costly and improving its performance.
Fraunhofer-Institut für Chemische Technologie (ICT).
Researchers at the German Aerospace Center (DLR) want to work together with partners to improve the production of fuels derived from solar energy. Scientists from a range of disciplines will work together in the Helmholtz Association funded Virtual Institute named SolarSynFuel.
To make a contribution as an alternative energy source for mobility and decentralised power generation, hydrogen must be produced efficiently and economically from renewable sources such as biological primary fuels. The work at the DLR Institute of Technical Thermodynamics focuses on process development, thermal management and gas treatment in the transformation and production of biogenic primary fuels.
The company CSP Services (a DLR spin-off) offers its global customers measurement techniques and assessment methods for the qualification of mirrors in solar power plants.
Fuel cells produce electricity directly from fuel gases. Here, the basic process is the electrochemical oxidation of hydrogen. The activities of the DLR Institute of Technical Thermodynamics range from cell design, manufacturing and diagnostics to system optimisation and demonstration to achieve cost-effective and efficient solutions for mobile and stationary applications.
Plasma spraying equipment at the DLR Institute of Technical Thermodynamics.
Researchers at the DLR Institute of Combustion Technology are developing special combustion systems in Stuttgart.
Investigating electrochemical processes using laser radiation.
To aid the understanding of detailed processes in solid oxide fuel cells (SOFC), researchers at the DLR Institute of Technical Thermodynamics are working together with the Institute of Combustion Technology on a test facility in which the electrochemical processes can be studied by means of laser metrology – avoiding contact with the electrode surfaces.
Test facility for investigating high-temperature fuel cells at elevated pressure.
Nitrogen oxides play an unpleasant role during the combustion of fossil fuels. They are responsible for acid rain and are also harmful to the respiratory tract. DLR researchers have been able to demonstrate that the principle of flameless combustion (‘FLOX®’, or FLameless OXidation) in typical gas turbine conditions promises reliable combustion in power plants with low nitrogen oxides emissions.
Carbon dioxide free power plant: A new high-pressure test bench for investigating oxyfuel combustion processes has come into operation at the DLR Institute of Combustion Technology. With oxyfuel combustion, climate unfriendly carbon dioxide will be separated from emissions in power plants to keep it out of the atmosphere through subsequent sequestration. Instead of air, the fuel is burned with a mixture of pure oxygen and carbon dioxide. whereby the carbon monoxide is recirculated from the emissions.
To better understand the processes occuring in a combustion chamber, for example in power plants or aircraft engines, and thus to design environment-friendly and reliable combustion chambers, the DLR Institute of Combustion Technology has developed a high-speed laser measurement system that can determine the flame characteristics during combustion in gas turbines with high precision: it is 1000 times faster than previous methods and, for the first time, shows what happens to the flame in the combustion chamber in great detail.
Ceramics, natural stones, concrete, molten salt – these materials are crucial for the development of technically and scientifically attractive heat storage systems. Scientists at the DLR Institute of Technical Thermodynamics are exploring new materials and storage concepts for various uses – from industrial applications through to power plant technology.
The solar thermal power plant fed its full output of five megawatts into the grid for the first time on 25 January 2012. This power plant went into operation at the end of last year, and is the first parabolic trough collector array in which steam is generated directly in the collectors.
Electrolysis test stand with DLR-developed electrodes for alkaline water electrolysis. DLR researchers are working on more efficient methods of producing hydrogen by electrolysis.
The Institute of Solar Research is currently working on the development of concentrated solar systems for the generation of energy, heat and fuels. This contributes to a future sustainable energy supply based on renewable energies. In solat tower power plants, such as the one in Jülich, moveable mirrors (heliostats) follow the path of the Sun and concentrate the solar radiation on a receiver located on the solar tower. The receiver is made of porous ceramic elements through which incoming ambient air flows. In passing through the receiver, the air is heated and this heat is delivered to the water-steam cycle in a heat recovery boiler. The steam generated there drives a turbine, which produces power via a generator.
The DESERTEC concept is based on the use of solar energy in Earth’s sun belt regions – preferably for solar thermal power plants – to produce environment-friendly electricity for Europe, the Middle East and North Africa. According to calculations performed by DLR, the energy produced in one square kilometere of desert could supply around 100,000 households with 250 million kilowatt hours of electricity per year.
DLR researchers at the Plataforma Solar de Almería in southern Spain calibrate measuring stations that will be used for a monitoring network in some North African countries.
A researcher from the DLR Institute for Solar Research tests a mirror for a solar-thermal power plant. DLR has developed its own test facilities and methods for verifying quality. In important areas, they have succeeded in developing internationally recognised quality standards.
Using artificial sunlight, researchers use this test stand to investigate the optical, geometrical and mechanical quality of the mirrors that capture and concentrate the sunlight in a solar power station, as well as the properties of the pipes that absorb the energy and transfer it in the form of heat.
The heliostat of DLR's solar furnace in Cologne collects the Sun's rays and reflects them onto the 'concentrator' – 157 separate, slightly curved and precisely aligned mirrors that focus the radiation. The radiation is concentrated by a factor of 5200 and falls on the approximately four-metre by four-metre test chamber of the solar furnace.
A 57 square metre mirror collects sunlight and directs it towards the facetted mirrors (left in the picture). These mirrors concentrate the incoming radiation up to around 5200 times and direct it to the research laboratory of the Cologne solar furnace (the beam of light can be seen on the right of the image).
‘alpha ventus’, situated 75 kilometres off the German North Sea coast, was the first offshore wind farm. The twelve wind turbines became operational in 2010. If companies and wind power equipment manufacturers find favourable conditions, the North Sea could become home to offshore wind farms with a combined generating capacity as high as 135 gigawatts by the year 2030. This is the result of a study conducted as part of an international project chaired by the Energy Research Centre of the Netherlands (ECN) and in which the German Aerospace Center (DLR) participated.
Scientists from the DLR Institute of Materials Research will use the 'TEG line' to further advance the development of thermoelectric materials and generators. They have around 400 square metres of laboratory space at their disposal.
The principle of thermoelectric generators seems straightforward. Heat is energy, and it is converted into electricity using a type of heat exchanger. On a daily basis, tons of waste heat arise as a 'by-product'- computers, cars, chimneys, even people and animals give off excess heat (energy).
The solar tower power plant in Jülich serves as a pilot plant and reference for commercial power plants in Southern Europe and North Africa. A nearly identical power plant is currently at the detailed planning stage in Algeria. Technology developed in Germany is being utilised in regions where solar radiation is highest. Here, solar thermal power plants have the greatest potential to play a major role in the desert electricity project DESERTEC.
At the Jülich site, set up on an area covering about eight hectares, are 2153 moving mirrors that concentrate the solar radiation onto a receiver atop the 60-metre tower.
Studies have demonstrated the vast potential of solar power; for example, the deserts on Earth receive more solar energy in just six hours than the world's population consumes in an entire year. To enable the cost-efficient conversion of solar power into electricity, solar cells and solar thermal power stations need to operate more efficiently and become much less expensive to build.
This image shows the experimental solar power plant with Fresnel collectors. These consist of several rows of moveable flat mirrors that capture the sunlight and concentrate it on a box located above the absorber tube.
The German Aerospace Center (DLR) and Endesa test direct solar steam generation and energy storage in this pilot plant in Carboneras, located in southern Spain. In this type of solar power plant, steam is produced directly from concentrated solar radiation and used to drive a generator. The highlight of this facility is a new system that efficiently stores energy, both as sensible and latent heat. The stored energy can be used to generate electricity even at night.
So far, thermal oils are used in parabolic trough power plants. Thermal oil flows into the absorber tube (dark pipe on the left). On these absorber tubes parabolic mirrors focus the light, here the solar radiation is converted into heat with a conventional power plant process steam is generated. In the now developed test system molten salt flowing through the absorber tubes.
A fuel cell system delivers electrical energy capable of powering the nose wheel of a 70-ton aircraft.
Last visual check: DLR employee Miriam Ebert checks to ensure that the ceramic fibres protecting the radiation receiver are well sealed. The test power station Solhyco has been constructed in a 60-metre-high solar tower at the Plataforma Solar de Almería in southern Spain. The sunlight that the mirrors direct on to the radiation receiver in the tower heat the absorber tubes to 800 degrees Celsius. The radially arranged black tubes conduct this heat to a 100-kilowatt micro gas turbine, which drives a generator that in turn produces electricity.
With the combustion chamber, the scientists at the DLR Institute of Combustion Technology can research synthetic gas with a high percentage of hydrogen under real conditions.
The high-pressure combustor rig Stuttgart (Hochdruckbrennkammer-Prüfstand Stuttgart ; HBK-S) is characterised by an excellent optical access for laser diagnostics. Sophisticated optical diagnostics together with classical measuring techniques allow the development of burner and combustion systems for gas turbines (stationary and aero engines).
A glimpse into the heart of a gas turbine: the combustion chamber.
The future is electric. Efficient, inexpensive and safe batteries are the basis for fully electrically-powered or hybrid vehicles. The Institute of Technical Thermodynamics is working on the development of high-performance batteries with lithium-air and lithium-sulfur architecture. An X-ray diffractometer is used to investigate battery materials.
1978: For the first time, a car in Europe is fuelled with hydrogen.
DLR CC-BY 3.0.