Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Molten Salts for Efficient Solar Thermal Plants

07.03.2011
Researchers from Siemens intend to substantially boost the efficiency of solar thermal power plants and thus reduce the costs of this climate-neutral method of power generation.

They intend to use mixtures of molten salts as heat transfer media in the High Performance Solar Thermal Power project. In conjunction with partners, scientists from Siemens will construct a pilot plant in Portugal and test the use of molten salt mixtures in parabolic trough power plants.

This type of power plant uses concave parabolic mirrors that focus sunlight on an absorber tube at the mirrors’ focus. A heat transfer medium flows along the tube. The heat is transferred to a conventional water-steam cycle in a downstream steam generator, where it is converted into electricity by a steam turbine and a generator. The main factor determining the efficiency of the power generation process is the maximum working temperature of the heat transfer medium. As this temperature increases, the utilization of the steam turbine approaches its optimum value.

Siemens intends to use molten salts instead of thermal oil, thereby increasing the working temperature from 400 to more than 500 degrees Celsius. Eliminating the use of thermal oil would also prove beneficial as it has a relatively high vapor pressure and is highly flammable. Salts suitable for use as heat transfer media consist of, for example, a mixture of sodium and potassium nitrates. These are non-flammable and have almost zero vapor pressure. As a result, the plant can be operated without pressure—and that means more safely. Furthermore, salts have a higher heat storage capacity than thermal oil and are considerably cheaper. The solidification temperature of the salt previously used for this purpose must, however, be reduced from the current temperature of approximately 220 degrees to less than 150 degrees Celsius so that it doesn’t “freeze” overnight. Optimizing the composition of the salt mixture and thus its physical properties is an important goal being pursued by scientists from Siemens Corporate Technology and from Siemens Energy.

The pilot plant will be constructed on the grounds of the University of Evora, Portugal. The solar components, the steam generator system, the pipework system, and the pumps will be adapted to cope with the higher temperatures and the properties of the molten salt mixture. The researchers will use the results gained to plan, and implement verification procedures at, commercial facilities with installed powers in excess of 50 megawatts. The project is being funded by Germany’s Federal Ministry for the Environment. The participants include the German Aerospace Center (DLR) and other companies.

Dr. Norbert Aschenbrenner | Siemens InnovationNews
Further information:
http://www.siemens.com

More articles from Power and Electrical Engineering:

nachricht Harvesting the Sun for Power and Produce
24.11.2017 | Fraunhofer-Institut für Solare Energiesysteme ISE

nachricht Batteries with better performance and improved safety
23.11.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New proton record: Researchers measure magnetic moment with greatest possible precision

High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons

The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

IceCube experiment finds Earth can block high-energy particles from nuclear reactions

24.11.2017 | Physics and Astronomy

A 'half-hearted' solution to one-sided heart failure

24.11.2017 | Health and Medicine

Heidelberg Researchers Study Unique Underwater Stalactites

24.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>