The Conventional Solar Power is generated using Photovoltaic cells and generated power has to be used immediately or stored in batteries for later use. Intermittent sources of renewable energy, such as solar power, pose a “storage problem.”

US and Swiss researchers has developed a device which can convert sun rays directly into fuel which can be stored for later use or may be moved to another location. This device uses a quartz window and a cavity to focus sunlight into a cylinder lined with cerium oxide, also known as ceria.

A BBC report citing  paper appearing in the journal Science describes this prototype device that uses a quartz window and cavity to concentrate sunlight into a cylinder lined with cerium oxide. Cerium oxide, also known as ceria, is hygroscopic (it attracts and holds water molecules from the surrounding atmosphere) and will also absorb a small amount of carbon dioxide. When sunlight heats the ceria, it thermo chemically breaks the water and then carbon dioxide pumped into the cylinder to generate carbon monoxide and hydrogen which can be transformed into liquid fuel.

The generated hydrogen can be used as fuel for hydrogen fuel cell vehicles which is being used by car makers like Hyundai and Honda. The combination of hydrogen and carbon monoxide can be used to create syngas – a combustible gas that has less than half the energy density of natural gas. The syngas can be used as a fuel source or as an intermediate for the production of other chemicals. The device can be used for methane generation as well. As cerium is available in abundance , this research can be developed commercially.

Because conventional photovoltaic panels produce electricity directly from sunlight, the energy they generate must either be used as it is produced or stored – either in batteries or by using the electricity to produce a fuel that acts as a storage medium for the energy. Now U.S. and Swiss researchers have developed a prototype device that directly converts the Sun’s rays into fuels that can be stored, allowing the energy to be used at night or transported to locations where it is needed.

A BBC report citing a paper appearing in the journal Science describes how the prototype device uses a quartz window and cavity to focus sunlight into a cylinder lined with cerium oxide. Cerium oxide, also known as ceria, is hygroscopic (meaning that it attracts and holds water molecules from the surrounding environment) and will also absorb a small amount of carbon dioxide. As the sunlight heats the ceria, it thermochemically breaks down the water and carbon dioxide pumped into the cylinder to produce carbon monoxide and hydrogen that can be converted to a liquid fuel.

The resultant hydrogen could be used as fuel for hydrogen fuel cell vehicles such as those being developed by a number of automakers, including Hyundai and Honda, while a combination of hydrogen and carbon monoxide could be used to create syngas – a combustible gas that has less than half the energy density of natural gas but is often used as a fuel source or as an intermediate for the production of other chemicals. The researchers say the device can also be used to produce methane.

With cerium being the most abundant “rare-earth” metal, the developers of the device from the California Institute of Technology and the Swiss Federal Institute of Technology say it would be economically feasible to use the technology on a large scale.