The role of bioenergy in the global energy supply
Popp, József
Keywords: energy supply, renewable energy, bioenergy, biofuels, environment
The aim of energy policy is to minimise energy prices and the risks in energy supply, and to reduce the negative environmental consequences of energy use. Owing to the high dependency of fossil energy the imports of energy and the diversification of en-ergy supply will gain more importance in the European Union (EU). On a global basis, it is estimated that renewable energy accounts for 13% of the total primary energy sup-ply. The largest contributor to renewable energy with 10% points is biomass. About 87% of the biomass feedstocks are derived from wood (trees, branches, residues) and shrubs, and just 10% of feedstocks come from the agricultural sector (energy crops, residues and by-products). Renewables will increase from 13% of the global primary energy mix to 19% in 2035 leading to a decreasing share of fossil fuels in the global primary energy consumption from 87% to 81%. Liquid biofuels play an important role in global road transport fuel consumption as 60% of oil is used for transport fuel and 96% of vehicles are dependent on petroleum. In addition the passenger vehicle fl eet will double to 1.7 billion by 2035. However, liquid biofuels make a small but growing contribution to fuel usage worldwide. Today there is not yet an alternative for biofuels. Banks are cautious about lending money which means that more sources of capital are needed. Strong competition from other renewable energy projects with lower risks (specifically wind) can be experienced. The solar and wind sector will continue to ex-pand with a combined share of 70% in total expenditure on renewable energy projects in 2020.
Changes in land use are mainly infl uenced by biofuels production. The proportion of global cropland used for biofuels is currently some 2.5% with wide differences among countries and regions. By adding by-products substituted for grains and oilseeds the land required for cultivation of feedstocks declines to 1.5% of the global crop area. The U.S. renewable fuels standard requires fuel distributors to increase the annual volume of biofuels with a specific quota for advanced biofuels in order to reduce conventional biofuels production from maize and oilseeds. The EU is targeting 10% of transport en-ergy from renewables by 2020. However, the European Parliament is discussing a draft on increasing advanced biofuels production and limiting conventional production to up to 5% of transport energy. Energy-related carbon dioxide emissions in 2010 are estimated to have climbed to a record 30.6 Gigatonnes. Scientists warn that if the cur-rent trend to build high-carbon generating infrastructures continues, the world’s car-bon budget will be swallowed up by 2017, leaving the planet more vulnerable than ever to the effects of irreversible climate change. Hungary will increase the share of renew-ables in the total energy supply from the present 7.4% to 14.6% in 2020. To meet the target is questionable since 77% of the renewable energy is derived from wood and wood residues. The share of nuclear energy in electricity production is around 44% and the increase of nuclear energy production will be associated with huge costs which may decrease the financial resources available for the support of renewable energy production.
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