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Not waste per se, but interesting still as this gives a good global picture of the renewable energy scene with projections. The share of renewable energy in the world’s primary energy supply will continue to decline over the next 30 years, according to the International Energy Agency.
Renewables contributed 13.8 per cent of the world’s primary energy in 2000, up from 13.5 per cent in 1990 and 13.3 per cent in 1980, but down from its peak of 14.0 per cent in 1971, according to IEA’s ‘Renewables in Global Energy Supply’ fact sheet. The supply from renewables experienced an annual growth of 2 per cent over the last 30 years, almost identical to the annual growth in primary energy, although “new” renewables recorded annual growth of 9 per cent. The latter category includes solar, wind and geothermal, but excludes hydroelectric and biomass.
Due to a very low base in 1971 and recent development, wind experienced the highest increase of 52 per cent per annum, followed by solar at 32 per cent annual growth. Geothermal had annual growth of 8.8 per cent while tidal grew at 8.4 per cent. These four technologies contributed 0.5 per cent of the world’s primary energy in 2000, compared with 34.8 from oil, 23.5 per cent from coal, 21.1 per cent from natural gas, 6.8 per cent from nuclear, 11 per cent from biomass and waste, and 2.3 per cent from hydro.
The ratio for renewables will drop from the current 13.8 per cent, to 13.3 per cent in 2010, 12.9 per cent in 2020 and 12.5 per cent in 2030, predicts IEA. The document devotes an entire page to the dangers of comparing renewables, due to variations among countries.
Renewables are the second-largest contributor to global electricity production, accounting for 19 per cent of production in 2000, after 39 per cent from coal but ahead of the 17 per cent from nuclear and natural gas. Most electricity from renewables comes from hydro dams (92 per cent) followed by biomass and waste (5 per cent). “Although fast growing, geothermal, solar and wind accounted for less than 3 per cent in 2000.”
Assuming the continuation of present government policies and no major breakthrough in technologies, renewables will grow by 1.3 per cent per year (below the 1.7 per cent overall growth of the total energy demand) over the next 30 years. The drop in share from renewables is due principally to a slowdown in the growth of biomass and waste combustion, caused by the shift from traditional biomass to modern forms of energy in developing countries, as well as some reduction in the growth of hydropower. The “new” renewables will grow at 4.1 per cent per annum, but will still be the smallest component of renewable energy in 2030.
In OECD nations, the share of renewables will increase from 6.4 per cent in 2000 to 8 per cent in 2030, with most renewables used for generation of electricity. Under a scenario where new energy and environment policies are implemented, non-hydro renewables will grow by 4 per cent per year until 2030, compared with 2.7 per cent in the reference scenario.
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