Ключевые слова: alternative, background, bbt, blue, building, business, city, cityscape, clean, conservation, earth, eco, ecological, ecology, electric, electricity, energy, environment, environmental, flat, friendly, generator, green, house, icon, illustration, industry, isolated, mill, natural, nature, power, renewable, save, sign, solar, symbol, technology, tower, urban, wind, windmill, yujakr,