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 […]
Category: Renewable Energy
The Molten Carbonate Fuel Cell (MCFC)
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, […]
Available Resources and Technologies
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 […]
A Super Climate in the Greenhouse
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 […]
Aquifers as Seasonal Storage Systems
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 […]
The Basic Technology for Exploiting Wave Energy
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 […]
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 […]
Solar-Thermal Power as a Key Element
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 […]