Ключевые слова: alternative, battery, biomass, canister, clean, coal, dangerous, earth, eco, ecology, electric, electricity, energy type, fuel, funny character, generation, generator, geothermal, graphic design, heading, headline, hydrogen, industry, landfill gas, letter, lettering, light, modern, natural, nonrenewable, nuclear, photovoltaic, power plant, production, renewable, resource, solar panel, source, station, steam, sun, sustainable, turbine, typography, vector illustration, wind, windmill,