What is "Alternative Energy"?

There is an abundance of natural energy that we can harness depending on the levels of research and development into them, and into the commerciality of harnessing them on an industrial scale. But it is theoretically completely possible (regardless of the mandate for our planet) to get away from our dependence on fossil fuels and national electrical grids by turning to alternative sources of energy. It is paradoxical we call these natural energy sources "Alternative Energy" or "Green Energy" despite them being, in many cases, original forms of power that mankind used to use for centuries! This brief article is an overview of the most commercial-ready "alternative energies" that exist today.

Wind Energy

Wind energy is perhaps the most immediately recognised alternative energy as the proliferation of "wind farms" (and occasional opposition to them) attests. Harnessing wind-power is hardly new - many turbines look like old wind-mills. But turbine development continues to progress with power efficiency increasing and set-up costs decreasing. Design varies from the traditional wind-mill-style fan to more modern helix-shaped wings which pivot on a vertical axis. Wind turbines exist both to generate "mass" consumption electricity, as well as to provide for the needs of individual establishments (like houses). Green Energy (Eu) itself is analysing the latter type of turbine in order to recommend a product to the market.

Solar Energy

Solar energy is also not a "new" alternative energy concept, but its early history was blighted by poor power output and very high cost. Capturing solar energy requires the manufacture of photo-voltaic solar "cells" (or panels) which trap and concentrate "insolation" (the energy given off by the sun) and convert it directly into electricity or, in some cases, hot water or steam, which can then be used directly as a heat source, or as a power source for electrical turbines.

As with wind energy, solar energy creates absolutely no pollution and the technology has recently started to come of age, allowing more efficient capture and conversion of solar energy for less cost.

Ocean Wave Energy

Ocean wave energy is seen by governments and investors as having enormous energy generating potential, but as a fully commercial source of power, it is yet to have its day. There are two main types of ocean energy:

1) Harnessing the kinetic energy of waves. Commercial exploitation of this type of energy is still low but does exist. A generator has been in operation for some years in France now and is considered to be very successful. In and around the UK, there are experimental wave energy plants in Scotland and Ireland and the Spanish government has also commissioned a wave farm.

2) Ocean thermal energy conversion (OTEC) which theoretically offers a great source of energy but as yet is under-researched and consequently realistically offers no short term source of commercial green energy.

Hydro-electric power

Hydroelectric power has been commercially exploited for several decades now and where used, is a powerful source of clean, green electricity. There are obvious limitations as to the location of hydro-electric plants (e.g. where a huge potential difference is available in water inlet and outlet, either due to height of water, or volume). Because of the construction requirements, entry costs are also high. A throwback to water mills of olden times: some "run-of-the-river" or small and local hydroelectric generators are available but are not widely exploited.

Geothermal energy

Geothermal energy is abundant since it lies directly under-foot just a few miles below the earth's surface. This energy is produced by the differential between ambient surface temperature and the warming ground-effect of the earths core. Commercial deep geothermal energy "mining" is possible by turning water into steam to drive turbines which in turn generate electricity. However, domestic / business geothermal heating units exist on a less grand scale to simply exploit the potential difference between ambient and soil temperature in combination with a heat capacitor to generate home or office heating. There is still a lot of mileage to go into research and development of geothermal energy.

Waste Gas

Waste gas - mainly methane - is available from garbage tips, agriculture, ocean and lake beds and from industry (via exhaust emissions). Tapping methane from these sources would in part compensate for the otherwise harmful energy-pollution relationship of modern industry, domestic and commercial waste and and cattle farming. Methane is then used in fuel cells and can be used in standard gasoline generators. However more means need to become available to make extraction of methane from such sources more commercially viable and attractive to its producers.

Ethanol

Ethanol is a gasoline substitute and is available from the fermentation of high starch / sugar vegatable matter such as wheat, sugarcane, grapes, strawberries, corn, and even from wood chips and wood cellulose. Some debate questions the widespread commercial use of ethanol, versus its exploitation in specialist energy areas, but technologies for its extraction and distillation have been with us since the dawn of man (!) and are continuously being refined.

Bio-fuels

Biofuels, such as Biodiesel energy is extracted from the oils contained in plants such as oilseed rape. So far, the commercially exploitable sources of biodiesel have come from plants such as soyabean, rape seed, and sunflower. Biodiesel has so far been exploited by the farming industry, as an alternative crop product that is more commercially attractive now than sowing wheat and grain. The supply of the raw oil-producing plants has therefore meant that it is beginning to become commercially attractive to produce the fuel from them, which in turn has led to generation of alternative forms of demand for it. Biodiesel is a green energy because it burns far more cleanly than fossil-based diesel.

Nuclear energy

Our overview of alternative energy sources cannot be complete without a review of nuclear (or atomic) energy. Tarred with a huge environmental and health "black brush" due to the instability of early installations (remember Chernobyl) and the difficulty of disposing of old reactor cores, atomic energy itself - generated by the process of nuclear fission is nonetheless extremely efficient and can generate huge amounts of power. Nuclear power is a mainstay of France's electrical generation as the country never had the fossil fuels to exploit, unlike the United Kingdom (oil, gas and coal). Consequently France's nuclear industry is well developed with a safety record to match, and both French electricity and nucelar know-how are now exports to the UK.

About the Author: Mike Howard, Director of Green Energy (Eu) is a rapidly-emerging expert in the field of Green Energy and power-saving electrical products for the home and office. With more than twenty years experience in top-end building Mike is sole UK distributor of the renowned Redwell Infrared Heating systems.