Let’s say you have a basic wood-burning fireplace. Charming as it may be, this old-fashioned device pollutes the air and sends a large amount of its heat roaring out the chimney. But there’s no need to get rid of your old fireplace. You can insert an energy-efficient gas-burning fireplace. Many models produce the same comforting yellow-orange flames that you enjoy in a wood fireplace and even contain “logs” made of fireproof material so realistic you would have to look closely to tell the difference. And you don’t have to bother with wood and ashes.