renewable energy :: essays research papers

Fuel Cell: Fuel cells have been known to science for 150 years and have become the subject of intense research since World War II. A fuel cell generates electricity by producing a chemical reaction. It consists of two electrodes (cathode and anode), which is also where the reaction occurs. Hydrogen is the basic fuel cell, but all fuel cells also require oxygen, and both are supplied from external reservoirs. Most of the hydrogen and oxygen used, combine to form a harmless byproduct, namely water. Therefore, fuel cells generate electricity with very little pollution. It is the purpose of the fuel cells to produce an electrical current that can be directed outside the cell to do work, such as powering light bulbs or an electric motor. There are five different fuel cells, solid oxide, alkali, proton exchange membrane (40-50% efficiency), phosphoric acid, and molten carbonate. Biomass Energy: This is one of the oldest sources of energy known to man. Biomass energy is energy from organic matter. The organic matter contains stored sunlight in the form of chemical energy. Biomass fuel, which can be a liquid, solid, or gas, comes from plants, residues from agriculture or forestry, and the organic component of municipal and industrial wastes. Even the fumes from the landfills can be used. When the fuel is burned, the energy is released. The use of this energy has potential to greatly reduce greenhouse gas emissions. The waste generates about the same amount of carbon dioxide as fossil fuels but as the plants grow (for biomass purposes), carbon dioxide will be removed from the atmosphere. This is the major source of energy in the developing world. Wind Energy: Surface air currents that are warmed by solar rays create wind, which is an indirect source of energy. Wind farms consist of many