A sustainable energy supply

Transcription

1 A sustainable energy supply LU Biofuels Seminar 23 October 2009, Lund Pål Börjesson Environmental and Energy Systems Studies Lund University, Sweden Overall strategy ex. biofuels More efficient (reduced) transportation services fuels Renewable More efficient vehicles

2 Sustainability criteria 1) Land-use and energy efficiency 2) Greenhouse gas performance 3) Eutrophication and water pollution 4) Biodiversity and water resources 5) Forestry- & farmland productivity 6) Cost efficiency 7) Social aspects (labour conditions, human rights ) 8) Economic development (rural development, international trade, global equity ) 9) Etc -100 Energy & area efficiency - Biofuels Biofuel By-prod.-process By-prod.-cultivation Energy input-cultivation Energy input-process GJ per hectare and year 250 By-products "determine" the efficiency S.beet-biogas Willow-biomethane Maize-biogas S.beet-ethanol Willow-DME/methanol Ley crops-biogas Willow-FT-diesel Wheat-biogas Willow-ethanol (Southern Sweden average arable land) Wheat-ethanol Rape seed-rme

3 Increased biomass without displacement of food A. Increased productivity NO C. Expansion of cropland Lands of high competition and carbon stock High yields, intensively utilised Global cropland 1500 million ha Low yields, partly utilised C. Expansion of cropland Lands of low competition and carbon stock B. Increased utilisation of wastes and residues Socio-economic considerations developing countries A. Large-scale systems B. Small-scale systems Large-scale feedstock Company-owned/ rented land Small-scale feedstock Individual farmers/ cooperatives Small-scale feedstock Individual farmers/ cooperatives Large-scale plants Company-owned Hybrids Small-scale plants Farmers-/local company-owned Export potential + Competitive globally - Little value added to local communities Export potential - Less competitive + High value added to local communities Local markets - High risk + Value added to local comm. Ref. Adapted from Woods (2006)

4 Bio-refinery lignocellulose Energy output / biomass feedstock (%) Energy content in unrefined biomass (100%) Ethanol Electricity Heat (Current technology in northern Europe) Heat & electricity Ethanol, el. & heat Ethanol & pellet Biomass feedstock Biomass feedstock Pellet Heat Electricity Ethanol Bioelectricity or ethanol is this the relevant question? Transportation kilometres / GJ biomass Hybrids Fuel cells Plug-in hybrids Electric Internal combustion Ref. Åhman et al, 2009

5 Sustainable biofuels are Biofuels from conventional crops with high-value by-products Biofuels from lignocellulosic crops on suitable land of low competition Biofuels from wastes and crop residues Biofuels produced in combination with other energy carriers and high-value chemical products in optimised bio-refineries Biofuels produced in developing countries leading to high value added to local communities Biofuels used in vehicles with high efficiency, e.g. electric hybrid cars Biofuels, as well as all fuels, not needed due to more efficient transportation systems and reduced transportation demands