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RENEWABLE ENERGY ALTERNATIVES

Renewable energy resources hold great promise for replacement of fossil fuels in many applications. Renewables include a considerable number of proven and emerging technologies, which permit the execution of needed tasks presently performed by use of fossil fuels. Thus electricity can be produced from the light of the sun via photovoltaic cells on individual buildings or for communities of buildings, or for the production of central station power in vast arrays; from the heat of the sun, again for localized tasks like heating swimming pools, providing homes with hot water or space heating, or providing central station power using fields of parabolic collectors focused on a fixed hot water source or solar ponds; from the power of the wind; from the heat below the earth through various geothermal applications; from the power of ocean tides and waves; from the temperature variations between ocean surfaces and depths; from hydropower installations; from biomass crops grown for energy use or from crop waste cellulose to produce ethanol as a power fuel.

Use of renewable resources has grown markedly in the past decade due primarily to technology improvements and cost reductions. Many countries have significant renewable installations and programs. For example, Finland accesses about 30% of its electricity from renewable resources, 80% of which comes from biomass. India's Renewable Energy Development Agency (IREDA), created in 1987, implemented a $430 million renewables program supported by multilateral and bilateral loans of $255 million, installing 980 MW of wind power by 1998 (placing India fourth in world installations), 250MW of biomass- fueled power and about 40MW of solar. Over 2.5 million biogas plants have been installed and over 450,000 solar photovoltaic
systems. Indonesia has a goal of providing 1 million solar homes and already has delivered 200,000 systems towards this goal; installment purchases contributed to this success, with the assistance of World Bank and GEF loans.

Internationally, the use of wind energy was pioneered by Denmark, which is currently generating 7% of its electricity via wind energy. A goal of 10% has been set for 2005 and estimates for the year 2030 reach 40-50%. The basic support mechanism for wind energy in Denmark is a partial redemption of the Danish carbon dioxide tax levied on all electricity regardless of its origin. There are 4,800 wind turbines in Denmark, more than 80% are owned by wind energy co-operatives or by individual farmers. 100,000 families either own shares in wind co-operatives or own their own wind turbines. Wind Power has become a big business for Denmark; it exports windmills to 35 countries and Denmark now accounts for more than 50% of all the devices manufactured in the world.

A major market for renewable resources, particularly photovoltaic power, exists in the developing countries where some 2 billion people have no access to electricity. According to the World Bank, 24% of the urban population and 67% of the rural population in developing countries are without electricity today. This lack of grid electricity - and the fact that most developing countries are in the sun belt -- creates great opportunities for use of solar energy resources to provide basic services such as refrigeration, irrigation and lighting. Solar resources like photovoltaics are particularly economic when the very high costs of grid electrification can be avoided.

For lighting, a photovoltaic compact fluorescent light system would be 100 times more efficient than kerosene, and a half million times more efficient than candles, used in the rural areas of many developing countries to provide night lighting. Photovoltaic systems also would avoid the high costs of standard power plants and the transmission and distribution systems they require for electric lighting that ultimately converts less than 1% of their original fuel energy to light.

Renewable energy resources require substantial up front capital costs, but solar, wind and hydroelectric technologies achieve considerable savings from costless fuels and low maintenance requirements. For those technologies which are not yet commercially competitive, financing is required to assist with raising the necessary initial capital in the developing countries.

The main constraints on the more widespread use of non-hydro renewable resources are the need for improved technology and lower costs. There also are some environmental restraints. New hydroelectric dams involve flooding of large areas of land and thus create environmental problems and usually problems of displacement of people or agriculture. The dammed water also creates some carbon dioxide and methane (another greenhouse gas) emissions from decaying vegetation. Adding power to existing dams, however, does not create these problems. There is a considerable potential resource of electricity from small hydroelectric projects at dams built for other purposes. Wind and photovoltaic systems have some siting problems involving their aesthetics and some wind machines have problems with killing raptor birds that fly into the blades. With solar energy, legislation is needed to protect the sunlight access to the systems.

Today, hydroelectric power, geothermal generation, biomass, wind farms, and increasingly photovoltaics in developing countries are well enough established technologically and sufficiently inexpensive to be utilized for supplying electricity to power grids. Photovoltaic cells also are economic and being used for remote power installations in where no grid exists and for niche applications, like powering transformers, marine navigation buoys and space vehicles.

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