Solar energy project at the Weizmann Institute promises to advance the use of hydrogen fuel

August 5, 2005

Innovative solar technology that may offer a "green" solution to the production of hydrogen fuel has been successfully tested on a large scale at the Weizmann Institute of Science in Israel. The technology also promises to facilitate the storage and transportation of hydrogen. Results of the experiments will be reported in August at the 2005 Solar World Congress of the International Solar Energy Society (ISES) in Orlando, FL.

The solar project is the result of collaboration between scientists from the Weizmann Institute of Science, the Swiss Federal Institute of Technology, Paul Scherrer Institute in Switzerland, Institut de Science et de Genie des Materiaux et Procedes - Centre National de la Recherche Scientifique in France, and the ScanArc Plasma Technologies AB in Sweden. The project is supported by the European Union's FP5 program.

Hydrogen, the most plentiful element in the universe, is an attractive candidate for becoming a pollution-free fuel of the future. However, nearly all hydrogen used today is produced by means of expensive processes that require combustion of polluting fossil fuels. Moreover, storing and transporting hydrogen is extremely difficult and costly.

The new solar technology tackles these problems by creating an easily storable intermediate energy source form from metal ore, such as zinc oxide. With the help of concentrated sunlight, the ore is heated to about 1,200°C in a solar reactor in the presence of wood charcoal. The process splits the ore, releasing oxygen and creating gaseous zinc, which is then condensed to a powder. Zinc powder can later be reacted with water, yielding hydrogen, to be used as fuel, and zinc oxide, which is recycled back to zinc in the solar plant. In recent experiments, the 300-kilowatt installation produced 45 kilograms of zinc powder from zinc oxide in one hour, exceeding projected goals.

The process generates no pollution, and the resultant zinc can be easily stored and transported, and converted to hydrogen on demand. In addition, the zinc can be used directly, for example, in zinc-air batteries, which serve as efficient converters of chemical to electrical energy. Thus, the method offers a way of storing solar energy in chemical form and releasing it as needed.

"After many years of basic research, we are pleased to see the scientific principles developed at the Institute validated by technological development," said Prof. Jacob Karni, Head of the Center for Energy Research at Weizmann.

"The success of our recent experiments brings the approach closer to industrial use," says engineer Michael Epstein, project leader at the Weizmann Institute.

The concept of splitting metal ores with the help of sunlight has been under development over the course of several years at the Weizmann Institute's Canadian Institute for the Energies and Applied Research, one of the most sophisticated solar research facilities in the world, which has a solar tower, a field of 64 mirrors, and unique beam-down optics.

The process was tested originally on a scale of several kilowatts; it has been scaled up to 300 kilowatts in collaboration with the European researchers.

Weizmann scientists are currently investigating metal ores other than zinc oxide, as well as additional materials that may be used for efficient conversion of sunlight into storable energy.

Source: Weizmann Institute of Science

Explore further: Plantations of nanorods on carpets of graphene capture sun's energy

Related Stories

Researchers use liquid inks to create better solar cells

September 17, 2014

(Phys.org) —The basic function of solar cells is to harvest sunlight and turn it into electricity. Thus, it is critically important that the film that collects the light on the surface of the cell is designed for the best ...

Simulations for better transparent oxide layers

September 1, 2014

Touchscreens and solar cells rely on special oxide layers. However, errors in the layers' atomic structure impair not only their transparency, but also their conductivity. Using atomic models, Fraunhofer researchers have ...

Recommended for you

Magnetism at nanoscale

August 3, 2015

As the demand grows for ever smaller, smarter electronics, so does the demand for understanding materials' behavior at ever smaller scales. Physicists at the U.S. Department of Energy's Ames Laboratory are building a unique ...

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Study calculates the speed of ice formation

August 3, 2015

Researchers at Princeton University have for the first time directly calculated the rate at which water crystallizes into ice in a realistic computer model of water molecules. The simulations, which were carried out on supercomputers, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.