Related by context. Frequent words. (Click for all words.) 52 energy 51 renewable 50 renewable energy 50 fossil fuel 49 fossil fuels 47 renewable energies 46 biomass 46 decarbonise 46 biofuels 46 nonrenewable resources 46 alternative fuels 46 renewables 46 bio fuels 45 emit CO2 44 alternative energies 44 decarbonisation 44 Fossil fuels 44 co2 44 fuels 43 greenhouse gases GHGs 43 biofuel 43 fuel 43 Renewable fuels 43 pollutions 43 rice husk 42 waste 42 GHG emission 42 hydro geothermal 42 biowaste 42 terawatts 42 solar panels wind turbines 42 carbon emitting 42 sulfur fuels 41 bio diesel 41 renewable fuels 41 biomass geothermal 41 feedstock 41 polluting fossil fuels 41 CO -2 41 Rainwater harvesting 41 petro chemicals 40 desalinate water 40 greenhouse gases GHG 40 reducing carbon emissions 40 wastages 40 GHG reductions 40 environmentally benign 40 diesel 40 vegetable oils 40 hydrocarbons 40 SO2 emissions 40 greenhouse emission 40 curbing carbon emissions 40 agrofuels 40 carbon dioxide emission 40 CO ² 40 renewable feedstocks 40 electricity 40 greenhouse emissions 39 biomass feedstock 39 minerals 39 rice husks 39 desalinization 39 greenhouse gas emission reductions 39 polluting gases 39 bioenergy 39 petroleum 39 Co2 39 Renewable energy 39 biomass fuels 39 CO2 sequestration 39 biogas 39 petrochemicals 39 pollution 39 greenhouses gases 39 gaseous fuels 39 ethanol 38 sustainably 38 feedstocks 38 greenhouse gasses 38 cleaner fuels 38 hydroelectricity 38 carbon emission 38 liquefied coal 38 raw materials 38 efficient lightbulbs 38 coal 38 wastes 38 Cellulosic ethanol 38 Thorium 38 carbon emission reductions 38 greenhouse gas emissions 38 thorium 38 hydrocarbon 38 leaded petrol 38 reciprocating engines 38 solar photovoltaic cells 38 finite resource 38 nonrenewable 38 liquid fuels 38 carbon emissions