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 MCFC takes its name from its electrolyte of alkali car­bonates, which is used in molten form at the operating tem­perature of 650° C. The electric current is carried in the electrolyte by carbonate (CO32-) ions. Maintaining the charge transport within the electrolyte thus requires CO2 circulation between the fuel gas used and the air, […]

At present, the power consumers in the EU-MENA countries have no other choice but to pay the steadily-increasing price of power from fossil and nuclear fuels. This situation is ex­acerbated by the fact that fossil and nuclear fuels tech­nologies today still receive ca. 75 % of all public subsidies for the energy sector. This figure […]

by Roland Wengenmayr Large buildings full of people and machines that are sources of heat are a challenge to air-conditioning engineers. This is especially true of alternative designs, which dispense with energy-consuming air conditioning and make the most of natural resources such as winds and the chimney effect. L arge buildings often present a challenge […]

The technology of aquifers as energy storage systems is in many respects closely related to hydrothermal-geothermal energy. The storage medium is the natural substratum, i. e. the rock layers and the deep water they contain; the latter also serves as heat-transport medium. Aquifer storage sys­tems are as a rule accessed via two boreholes or groups […]

Beginning in 1986, a simply-constructed wave power plant was built in Norway, where it was operated for about twelve years. The plant was on the island of Toftestallen near Bergen, and it was intended as a demonstration project for interested groups. The TAPCHAN (TAPered CHANnel) di­rects the water from the incoming waves into a channel […]

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 […]

Steam and gas turbines powered by coal, uranium, oil and natural gas are today’s guarantees of power-grid stability. They provide base-load and peak-load power. However, tur­bines can also be operated with high-temperature heat from concentrating solar collector fields (Figure 5). Solar thermal power plants of this type with 30 to 80 MW output power have […]