air pollution bio-diesel bio-energy bio-fuel bio-fuels biodegradable biodiesel biodiversity bioenergy biofuel biofuels biological diversity collectors? coppices? cost-sharing diesel engine dioxins? drinking water eco-efficiency eco-labels? ecosystem electronic waste emmisions? reduction emulsification emulsions emulsions? energy balance energy development energy efficient energy efficienw+ energy equipment energy ratios? energy reduction energy star program(me)? energy storage energy strategies energy strategy energy use energy window engine wear environmental quality environmentally sustainable ethanol ethanol made from grain ethanol made from stems of plants fresh water freshwater fuel consumption fuel efficiency fuel pump fuel pump sensor fuel pumps? fuel quality gaseous biofuel government requirements? greenhouse gas greenhouse gas(es)? reduction greenhouse gases heating systems? higher energy efficiency hydropower increase productivity landfill liquid biofuel liquid effluents? living conditions lower water usage methane methanol mineral diesel mortality municipal waste nuclear waste oil waste organic certification packaging waste pesticides? pollution control equipment pollution prevention poverty recyclable reduction in usage risk-sharing sanitation sensor solar solar collectors? solar energy solar generated electricity solar heating solar water solid biofuel solvent to vegetable oil ratio space heating species straight vegetable oil sugars as fuels sustainability sustainable sustainable development sustainable energy torque toxic waste transesterification trombe wall used vegetable oil vegetable carbohydrates vegetable oil viscosity viscosity reduction waste cars? waste disposal waste management waste minimization waste oil waste production waste recycle waste reduction waste streams? waste systems? waste transportation waste vegetable oil waste water waste water treatment water contamination water efficiency water heating water pollution water scarcities water scarcity water supplies water supply water treatment water usage white spirit wind energy

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