Category: Renewable Energy

Energy Reserves from the Oceans

BY KAI-UWE GRAW An old dream of humanity is to make use of the almost im­measurable energy of ocean waves. Their destructive power has however up to now not permitted any economically rea­sonable design to survive for long, although there have been many promising attempts and approaches. T he reduction in carbon dioxide emissions, which […]

The New Scenario for Hydrogen

With regard to energy technology, hydrogen has become rel­evant again today due to environmental problems. The ex­tensive combustion of fossil fuels such as coal, petroleum and natural gas is a large-scale intervention by mankind in­to the natural balance of the earth. The global warming pro­voked by the increasing concentration of CO2 in our at­mosphere will […]

The Solid-Oxide Fuel Cell (SOFC)

In the SOFC, a thin ceramic layer of yttrium-oxide-doped zir­conium oxide (YSZ) serves as electrolyte, allowing the pas­sage of oxygen anions at its operating temperature of 900 to 1000° C. The power output of the systems currently being test­ed ranges from one kilowatt for household energy provision using natural gas up to a pressure-driven 200 […]

Hydrogen in the Gas Tank

As the lightest element, hydrogen has a high mass-specific energy storage density of 120 MJ/kg. This corresponds to about three times the storage density of diesel fuel, at 43 MJ/kg, referred to the so-called lower heating value. How­ever, this physically favorable property of hydrogen cannot readily be applied in a technological setting. While an automobile […]