Ключевые слова: alternative, autumn, bio, biofuel, biological, biomass, brown, burn, closeup, compressed, cylinder, eco, ecological, ecology, economy, energy, environment, environmental, fire, fireplace, firewood, fuel, granule, heap, heat, heating, industry, leaf, material, natural, nature, particle, pellet, pine, power, recycling, renewable, table, timber, winter, wood, wooden,