Finland is one of the leading industrialised countries to use renewable energy. Bioenergy has been the most important among used renewable sources.SolarThe solar energy reaching Finland from the sun annually amounts to 1,000 kWh per square metre. In Finland solar energy systems have so far mainly been used in locations not connected to conventional power grids. Such locations and uses include many holiday homes, boats and ships, navigational markers, mobile communications masts, and buildings on islands or in remote areas.Solar energy systems connected to the grid are becoming more common, however, as more people are realising that solar energy - even in Nordic countries - can also be exploited to provide a considerable proportion of the electricity used in a typical home, for instance.Wind EnergyMany localities in Finland would be suitable for the generation of wind power, including coastal sites, coastal waters of the Baltic Sea, and the exposed fells of Finnish Lapland. Surveys have indicated that the total potential for wind power in marine waters alone amounts to tens of terawatt-hours a year.The 2008 National Climate and Energy Strategy includes a target that six terawatt hours a year should be generated using wind power in Finland by 2020. This would necessitate an increase in total national wind power capacity to around 2,500 MW.BioenergyBiomass accounts for a larger share of energy consumption in Finland than in any other industrialised country. Wood and wood-based residuals from Finland’s large-scale pulp and paper industry, including black liquor derived from pulp-making processes, account for as much as 97.5 % of the bioenergy produced in Finland. Solid recovered fuels, biogas, energy crops like reed canary grass and organic liquid fuels make up the remaining 2.5%.Wood directly or indirectly accounts for as much as a fifth of the energy used in Finland. The largest users of wood energy are the forest industry companies, who produce large quantities of energy from residual wood such as bark, sawdust and woodchips, as well as the wood-based by-products of pulp and paper making processes, including black liquor.So far only relatively small amounts of bioenergy have been generated in Finland using energy crops, recovered fuels, liquid biofuels or biogas. But the importance of these bioenergy sources is growing rapidly as climate-friendly alternatives are sought to non-renewable fossil fuels, whose prices can be expected to rise considerably due to their declining reserves, as well as future climate policies.HydroHydropower accounted for about 4% or Finland’s total energy consumption in 2008. Hydropower’s share of electricity production in Finland has varied in recent years within the range 10-15%, depending on precipitation levels and other hydrological conditions. Hydropower is Finland’s second most widely exploited renewable energy source, after bioenergy. In 2007 hydropower provided 14% of the renewable energy produced in Finland.The total unexploited hydropower potential along river systems that are not protected for landscape or nature conservation is estimated at more than 600 MW, corresponding to annual production of over two terawatt-hours. Almost 400 MW (0.4 TWh/year energy potential) of this unexploited capacity lies on river systems that have already been harnessed to some extent. It is unlikely that hydropower developments could be launched along any remaining totally unharnessed rivers, for conservation reasons.