Related by context. Frequent words. (Click for all words.) 91 biofuels 81 biodiesel 81 bio fuels 79 ethanol 75 cellulosic ethanol 73 bioenergy 72 alternative fuels 72 bio diesel 72 renewable fuels 71 biomass 69 Biofuels 63 Ethanol 63 renewable energy 62 Biodiesel 60 fossil fuel 60 renewable 60 feedstocks 60 switchgrass 58 fossil fuels 58 feedstock 57 Biomass 56 cleaner burning 55 fuels 55 hydrogen powered 55 fuel 54 renewables 54 renewable energies 54 Renewable energy 53 Renewable 53 biogas 53 genetically modified crops 53 hydrogen fuel 53 hydrogen 53 diesel 52 sugar cane 52 cellulose 52 palm oil 52 carbon capture 51 carbon sequestration 51 vegetable oils 50 carbon dioxide emissions 50 diesel fuel 50 organic farming 50 corn 49 reduce carbon emissions 49 CO2 49 soy 49 greenhouse gas 49 reducing carbon emissions 49 sugarcane 49 environmentally sustainable 49 carbon emissions 48 greenhouse gas emissions 48 flex fuel 48 greenhouse gases 48 greenhouse emissions 48 Algae 48 carbon dioxide 48 soybean 48 carbon 48 algae 47 carbon emission 47 Renewable Energy 47 emissions 46 environmentally friendly 46 Hydrogen 46 zero emission 46 sorghum 46 genetically modified 46 emission reduction 46 aquaculture 46 Fuel 45 CO2 emissions 45 wood chips 45 soya 45 gasification 45 agricultural 45 GMOs 45 fertilizer 44 Fuels 44 energy 44 Clean Energy 44 methanol 44 Renewables 44 soybeans 44 photovoltaics 44 petroleum 44 Alternative Energy 43 carbon neutral 43 carbon credits 43 gasoline 43 GHG emissions 43 reduce greenhouse gas 43 crop yields 43 agribusiness 43 cassava 43 E# [004] 43 tar sands 43 cropland 42 cogeneration 42 crops