Related by context. Frequent words. (Click for all words.) 63 ethanol 60 biodiesel 58 flex fuel 55 renewable fuels 55 E# [004] 54 bio diesel 54 cleaner burning 54 diesel 52 biofuel 51 Ethanol 50 alternative fuels 50 diesel fuel 49 bio fuels 49 octane 48 gasoline 48 biofuels 48 unleaded gasoline 48 MTBE 47 Biodiesel 46 unleaded 46 bioethanol 45 LPG 44 compressed natural 44 diesel powered 44 reusable bags 43 fuel 43 diesel engines 43 renewable energy 43 renewable 43 CNG 43 cellulosic ethanol 42 petrol 42 petrol stations 42 hydrogen fuel 42 Caltex 42 hydrogen 41 hydrogen powered 41 EVs 40 refiners 40 zero emission 40 Biofuel 40 regular unleaded 39 diesels 39 Biofuels 39 Hydrogen 39 emissions 39 greenhouse gas 39 trans fat 39 electric hybrids 39 trans fats 39 RFS 38 convenience stores 38 emission 38 renewables 38 liter 38 dispersant 38 gallon 38 nitrogen oxide 38 Citgo 38 greenhouse gas emission 37 emission reduction 37 Fuel 37 greenhouse gases 37 hybrids 37 petroleum 37 liquid fuels 37 propane 37 additive 37 renewable energies 37 mileage 37 regular unleaded gasoline 37 refineries 37 internal combustion engines 37 kerosene 36 gas guzzlers 36 diesel engine 36 GMOs 36 additives 36 fossil fuels 36 Renewable 36 nitrogen oxides 36 fuels 36 greenhouse gas emissions 36 incandescent bulbs 36 excise tax 36 motorists 36 liquefied petroleum gas 36 internal combustion engine 36 CFLs 36 Propane 36 electric hybrid 36 Petrol 36 Renewable Energy 36 cigarettes 36 methanol 36 harmful chemicals 36 sulfur 36 biomass 35 corn crop 35 DEET 35 GHG emissions