Ключевые слова: alternative, background, bio, biofuel, biology, biomass, burn, closeup, domestic, eco, ecological, ecology, economy, emission, energy, environment, fire, fireplace, flowing, fossil, fuel, generation, granule, heap, heat, horizontal, household, industry, mass, materials, measurement, natural, nature, pattern, pellet, pellets, pine, power, recycling, renewable, saving, sawdust, solid, studio shot, timber, unit, winter, wood, wooden,