This section's articles

Wind Energy

Wind energy grows from strength to strength Large-scale wind energy is an increasingly important factor in global energy supply. Economic and population growth continues to lead to rapid increases in worldwide energy consumption. According to International Energy Agency (IEA) figures, between 1973 and 2006 total primary energy supply for all uses almost doubled and electricity generation more than tripled (the vast majority coming from fossil fuels – coal, gas and oil). By the end of 2008, (...)

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Hydro-Power

Hydropower was one of the first energy sources to be used by man. In ancient times, water mills were used to grind grain and to lift water. Mills were replaced with hydroelectric power plants in the middle of the 19th century. Currently 90% of all electricity generated through renewable sources is hydroelectric. How does it work? Hydropower uses the power of rivers or waterfalls, transforming the water’s driving force into electricity. The weight and speed of the water power a turbine and (...)

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Biomass

Biomass as a fuel refers to plants, animal wastes and other fuels of a biological origin. Since reserves of biomass can be readily replenished with organic growth, they are considered to be a renewable fuel. Energy produced with biomass is called bioenergy. [1] Some biomass fuels, such as wood, have been used throught history. Others, such as modern automotive biofuels, are results of highly sophisticated scientific research. The combined share of biomass derived fuels in global primary (...)

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Biofuel

Biofuel is a fuel produced with non-fossil organic material made from biomass (the term “biomass” covers all organic matter). Most biofuels come from agriculture so they are also referred to as “agrofuel”. Types of biofuel Biofuel can be made from several plant species: Oil-producing species produce vegetable oils such as colza, sunflower, palm oil and soya. Pressed grains produce oil which is ready-to-use. However, vegetable oils are usually refined and mixed with methanol so that their (...)

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Photovoltaics

What is Photovoltaic Energy? The word “photovoltaic” is a combination of two words - “photo”, meaning light, and “voltaic”, meaning electricity. Therefore photovoltaic technology, the scientific term used to describe solar energy, involves the generation of electricity from light. The secret to this process is the use of a semiconductor material which can be adapted to release electrons, the negatively charged particles which form the basis of electricity when exposed to light energy. The most (...)

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Solar Thermal Energy

Parabolic Trough Solar Collectors Large-scale solar thermal power plants use parabolic trough collectors. There are curved mirrored surfaces, usually coated with silver or polished aluminium, in a parabolic shape with a receiver tube running its length at the focal point. Sunlight is reflected by the mirror and concentrated on the tube. The trough is usually aligned on a north-south axis, and rotated to track the sun as it moves across the sky each day. Alternatively the trough can be (...)

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Geothermal energy

Geothermal power is obtained by using heat from the Earth’s interior. Naturally the internal heat of the planet manifests itself in hot springs, geysers and, more dramatically, volcanoes and earthquakes. It originates from radioactive decay and solar energy absorbed through the surface of the planet. The ancient Romans heated baths and houses with water from hot springs and similar uses are still found in some geothermally active regions of the world, such as Iceland, Turkey, and Japan. In (...)

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Wave/tidal energy

The motions in world’s oceans contain amounts of energy that dwarf our global energy consumption. Technologies are now emerging to harness two forms of these vast energy resources: the energy of the waves and the energy of the tides. The potential contribution of wave energy to the global electricity market is estimated to be on the order of 2000 TWh annually, approximately 10% of the world electricity consumption. The tidal energy potential available in comparatively shallow waters is (...)

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Energy Effciency/savings

Energy conservation is the practice of reducing the amount of energy used for a given process without overly compromising the outcome. According to many organizations such as the French Agency of Energy Management (ADEME) or CLER, energy efficiency should be an essential part of any renewable energy policy and climate protection. Energy management combines the use of many energy efficiency techniques with the aim of reduce energy consumption (e.g. of a building) to achieve both financial (...)

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In general

Renewable energy is derived from sources that are naturally replenished. Sources of renewable energy include wind energy, the Sun or solar energy, the flow of rivers or hydropower, the Earth’s internal heat or geothermal energy, waves, tides and other forms of ocean energy, and forests and other sources of biomass. [1] [2] The potential of renewable energy sources is enormous, because, in principle, their annual replenishment rate surpasses many times over the world’s annual energy (...)

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