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www.paccar.ethz.ch Well-to-tank efficiencies and -factors compared CO 2 Abbreviation and Explanations CI Compression-ignited or diesel engine CO 2 -Factor CO 2 emitted per energy relative to Oil CNG Compressed Natural Gas FC Fuel Cell NG Natural Gas PP Power Plant SI Spark-ignited or gasoline engine *Compressed only to 11bar **Results from Shell Eco-marathon in Nogaro 2005 and Ladoux 2005, distance per gasoline equivalent Different paths to convert a primary energy source to mechanical energy. Source: Dones R, Bauer C, Bolliger R, Burger B, Faist M, Frischknecht R, Heck T, Jungbluth N, Röder A (2004) Sachbilanzen von Energiesystemen: Grundlagen für den ökologischen Vergleich von Energiesystemen und den Einbezug von Energiesystemen in Ökobilanzen für die Schweiz. Final report ecoinvent 2000 no. 6., Paul Scherrer Institut 0.51 108.7 167.3 5385 FC Pac Car II ETH (CH), realistic 3.03 31.8 167.3 5385 FC Pac Car II ETH (CH), worst case 1.46 50.5 56.1 1807 CI-engine Schluckspecht FH Offenburg (D) 1.08 68.4 79.5 2560 SI-engine Univ. Paul Sabatier (F) CO 2 per km [g / km] Well-to-wheel [km / MJ] Tank-to-wheel [km / MJ] Tank-to-wheel** [km / l] Type of car Oil Gasoline data used: density 0.74kg/l, lower heating value 43.5 MJ/kg, CO 2 emission per energy 74g CO2/ MJ Hydrogen can be generated electrolyzing water using electricity from renewable energy sources or nuclear power plants. Then, hydrogen is almost CO 2 neutral. Well-to-tank calculations for renewable energy sources can’t be compared with the ones of fossil fuels. Crude Oil CI Engine 1 90% 100 90 Refinery, Transport Diesel Oil Crude Oil SI Engine 1 86% 100 86 Refinery, Transport Gasoline 0 Solar Energy Fuel Cell Natural Gas Fuel Cell NG NG H 2 0.75 91% 97%* Transport Compr. 74% Steam Reforming Compr. H 2 65 100 91 67 Coal Fuel Cell 1.3 Coal Coal Electricity Electricity H 2 80% 94% 76% 97%* 100 80 28 26 20 19 Digging, Transport Electric Grid Electrolysis Compr. 35% Coal Power Plant Compr. H 2 [joules] [CO 2 Factor]
