Related by context. Frequent words. (Click for all words.) 63 biofuel 61 biofuels 58 cellulosic ethanol 58 alternative fuels 57 camelina 57 cellulosic 55 cellulosic biofuels 55 biobutanol 55 biodiesel 55 Solazyme 53 Biofuel 53 renewable fuels 53 jatropha 52 alternative energies 52 bio fuels 52 corn ethanol 52 renewable energy 51 bioenergy 49 butanol 49 bio diesel 49 feedstocks 49 switchgrass 49 hydrogen fuel 48 ethanol 48 biobased 48 hydrogen powered 48 commercially viable 48 algae 48 carbon capture 48 cleaner fuels 48 renewable 48 Coskata 47 Alternative Fuels 47 environmentally benign 47 biomass 47 Jatropha 47 carbon sequestration 47 Amyris 47 biorefinery 47 coal gasification 47 Biofuels 47 synthetic fuels 46 Algae 46 microalgae 46 environmentally friendly 46 Syntroleum 45 Iogen 45 algal 45 biorefineries 45 bio ethanol 45 hydrogen 45 environmentally sustainable 44 renewables 44 PHEVs 44 woody biomass 44 sweet sorghum 43 Biodiesel 43 bioplastics 43 EERC 43 PHEV 43 Aptera 43 nanotechnology 43 environmentally sound 42 hydrogen fueling 42 Codexis 42 LS9 42 reduce carbon emissions 42 biofuel crops 42 corn stover 42 E# ethanol 42 fossil fuel 42 Renewable 42 Bioenergy 42 OriginOil 42 zero emission 42 cleaner greener 41 cleantech 41 fossil fuels 41 bioethanol 41 renewable energies 41 cleaner burning 41 anaerobic digestion 41 biochar 41 Alternative Fuel 41 ecologically friendly 41 Rentech 41 Hydrogen 41 Renewable energy 41 ARPA E 41 smart grid 41 electric propulsion 41 feedstock 41 technologies 40 Renewables 40 economically viable 40 liquid fuels 40 desalination 40 Clean Energy 40 Carbon Capture 40 genomics 40 carbon emitting