Renewables include a considerable number of proven and emerging technologies, which permit the execution of needed tasks presently performed by use of fossil fuels. 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.
Over 2.5 million biogas plants have been installed and over 450,000 solar photovoltaic systems. 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. 100,000 families either own shares in wind co-operatives or own their own wind turbines. A major market for renewable resources, particularly photovoltaic power, exists in the developing countries where some 2 billion people have no access to electricity. Solar resources like photovoltaics are particularly economic when the very high costs of grid electrification can be avoided.