There are ways to save energy in your home that require investments in auxiliary heating or cooling equipment. Some of those options are listed below.
Wood -- a Renewable Fuel
Wood, of course, has been used as a heating fuel for as long as people have been on the earth. In the overall span of that time, only relatively recently have people sought to increase the benefit of wood's heat-producing ability by containing the burning process inside a metal enclosure.
A variety of high-efficiency wood-burning stoves, fireplaces, and fireplace inserts are currently on the market.
Wood can be used as a primary heat source but more often plays a supplementary role to a central heating furnace or boiler. And while burning wood can reduce our dependence on oil or gas, the fact remains that wood has to come from somewhere. You have to purchase it or cut it, split it, stack it, and store it yourself. But for those with access to an inexpensive or free supply of wood, installing and using a wood-burning stove or insert can make a dramatic difference in your utility bill.
Fireplaces -- Not So Efficient
Burning wood in an older, conventional fireplace is not the best way to generate heat; the wood burns uncontrollably and inefficiently. In fact, 90 percent of the heat energy produced goes up the flue, along with a lot of dirty smoke. Worse, this type of fire gobbles up a huge amount of room air that is used to help combust the fuel and convey it up the chimney. That air is drawn into the house from many different places: It leaks through and around windows and doors, and cracks and gaps in the exterior siding and foundation. It is possible to sit in a room that has a roaring fire blazing in an open fireplace, yet still feel a cold draft of air at your back as air rushes toward the fire.
Glass doors on the front of an open fireplace help increase the efficiency, but there is still a lot of heat going up the flue that could better be used to heat the house.
A cast iron or steel fireplace insert mounted inside an open fireplace provides many of the benefits of a wood-burning stove. The metal radiates heat into the room, an adjustable opening on the front of the insert allows control of the air going into the firebox for more efficient burning, and many inserts are available with glass panels in the doors, which provide a view of the fire. Nearly any open fireplace can be retrofitted with an insert, and the difference in the heat produced is well worth the effort and expense.
Cast-iron, steel, or stone woodstoves can be both beautiful and efficient. Like fireplace inserts, the metal radiates heat in all directions, the burning of the fire is controlled by regulating the flow of air into the firebox, and many stoves come with glass panels that allow the fire to be seen. A surround made of masonry material can soak up heat while the fire is burning and later radiate it into the house, acting as a heat-storage device.
A drawback to woodstoves is that they take up space in the home and might not be easily added to an existing home. A metal or masonry flue has to be provided for safe venting of the hot combustion gases, so a clear path from the stove to the roof has to be available. Additionally, as with any wood-burning device, hauling wood in and out during the heating season can be messy and might introduce insects into the home.