Biofuels A bad idea. Edgar Hertwich Industrial Ecology Programme.

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1 1 Biofuels A bad idea Edgar Hertwich Industrial Ecology Programme

2 2 Oversikt Mulig bidrag fra biodrivstoff Bivirkninger Klimanøytralitet Klimabidrag per landareal Bil og klima

3 3 Landbruk Dagens global matkonsum 25 EJ/a Dagens global energibruk 400 EJ/a Dyrket mark dyrket mark og beite Mulige tilleggsområder 1.8 Gha 5 Gha 0.7 Gha Landbehov for å dekke dagens fossil energibruk 3-6 Gha Professor Roland Clift Royal Academy

4 4 Konklusjon Dagens energibehov kan ikke dekkes gjennom biomasse Tilgjenglig land er en beskrankning

5 5 Corollaries Målsetninger for bioenergi Maksimere energiutbytte per areal Maksimere CO2 offset per areal i et livsløpsperspektiv Fossil brensel kommer å bli brukt over lengre tid Energieffektivitet er en nøkkel Invester i CCS

6 6 Beskrankninger til arealbruk Konkurranse mellom mat og energi Biomaterialer til andre formål Naturvern og biodiversitet Landskapsvern Vannbruk Bruk av kjemikalier

7 7 The Bornean orang-utan is almost extinct, mainly due to habitat loss

8 8 Klimanøytralitet Bioenergi er klimanøytral hvis den er dyrket på en bærekraftig måte dvs. ingen forandringer i karbon bundet i jord eller stående biomasse over lang sikt hvis energi brukt i dyrking, prosessering og for innsatsfaktorer er også karbonnøytral

9 9 Hill, PNAS 2006

10 10 Righelato* & Spracklen, Science, 17 Aug 2007

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13 13 Hva er klimavennlige biler? Der finns per i dag ingen teknisk løsninger for å gjøre biler klimavennlig. Plug-in hybrider er kanskje det beste. Da trenger vi først en CO2-fri strømkilde. Derfor bør vi prøve å redusere bilbruk og bygge en infrastruktur som ikke gjør oss avhengig av bil.

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15 INEFFICIENCY IN AGRICULTURE UNSUITABLE NATURE PROTECTION INFRASTRUCTURE URBAN LAND COVER 15 Yield from land use PRESSURE ON LAND USE Land Use

16 16 CULTIVATION OF BIOFUELS Perennial crops increase carbon inventory [e.g. willow (salix), poplar, miscanthus, switch grass] - do not require high inputs - usually have high water demand - employment per energy output typically 5 x fossil fuels Rotation crops [bioethanol, biodiesel] - do not build up soil carbon - require high agrochemical inputs - employment per energy output typically 20x fossil fuels

17 17 TYPICAL YIELDS FOR PERENNIAL CROPS: SRC (willow or poplar) Miscanthus Switch grass 7-14 Plant breeding may increase yields or enable use of lower quality land. Figures in oven-dry tonnes per hectare per year (ODT/ha/yr), from Rothamsted Research (TSEC-Biosys consortium)

18 18 POSSIBLE CONTRIBUTION IN UK Perennial crops on 10% of arable land and 50% of improved and set-aside grassland: - could contribute up to 45 TWh of electrical output (>10% of current use) - plus around 80 TWh heat (>80% of current CHP output). Estimates from University of Southampton (TSEC-Biosys consortium)

19 19 TRANSPORT FUELS (Larson) (The CONCAWE study) shows a range in reductions of GHG emissions per vehicle km for RME from 16% to 63%... The range for ethanol from wheat shows anywhere from a 38% GHG reduction up to a 10% penalty relative to gasoline. Emissions avoided per hectare do not appear to correlate with emissions avoided per vehicle km.

20 20 REMEMBER Objective is to maximise life cycle energy yield and carbon offset per ha subject to environmental and social constraints, many of which are local.

21 21 TRANSPORT FUELS (Larson, 2) conventional grain- and seed-based biofuels can provide only modest GHG mitigation benefits by any measure and will be able to provide only modest levels of fuel displacement due to high land requirements. More efficient land use in mitigating GHG impacts can be achieved in the longer term with dedicated high-yielding lignocellulosic energy crops. The US produced 3.4 billion gallons of ethanol in 2004, consuming 12% of all corn grown that year in the US. This ethanol accounted for less than 1.5% of US motor vehicle fuel use (on an energy basis).

22 22 IMPORTANCE OF LAND USE CHANGES In the UK: - being worked on (in TSEC-Biosys, by Scottish Agricultural College and University of Aberdeen). Tropical rainforest: - conversion to palm oil plantation releases GHG emissions which correspond to 70 to 300 years of carbon offset from palm oil biodiesel (and that s apart from the biodiversity impacts)

23 23 TRANSPORT FUELS Crude oil is not the only fossil source of hydrocarbons for transport Coal-to-liquids technology can produce crude oil substitute at about $80-100/bbl. Personal view: the car of the future is a plug-in hybrid with a hydrocarbon-fuelled engine This use of fossil fuels for transport is compatible with targets for reducing fossil carbon emissions (see RCEP, 2000)