Ключевые слова: alternative, background, biology, business, charge, clean, concept, creative, design, echo, ecology, electric, electrical, electricity, element, energy, environment, environmental, friendly, global, graphic, green, icon, illustration, industrial, industry, innovation, leaf, modern, natural, nature, panel, plant, plug, pollution, power, recycle, recycling, renewable, save, science, sign, solar, sun, sustainable, symbol, technology, tree, vector, voltage,