Heat pumps
Heat pumps
A heat pump is usually an electrically-powered system that can either heat or cool by transferring heat from one place to another. During the heating season, a heat pump extracts heat from either the air, ground or water outside the house, and transfers it indoors. In the summer the direction of the heat flow is reversed, extracting heat from indoors and transferring it outdoors, to provide air conditioning. Because they satisfy a substantial part of your heating needs by utilizing already available heat, rather than consuming electricity to generate all of the heat you need, heat pumps are significantly more efficient than electric resistance heating.
There are three main types of heat pumps:
Air source heat pumps
Earth energy systems
Bvalent heat pumps
Air source heat pumps
These most commonly-used heat pumps can provide all the cooling requirements of a home and most of the heating needs, but they require an auxiliary heating source during very cold weather. This can be either an electric resistance or a fossil fuel unit.
Earth energy systems
Also known as ground source heat pumps, these systems transfer heat from the ground, ground water or surface water and use it to provide home heating. For summer cooling, the process is reversed. If desired, earth energy systems can be equipped to provide domestic hot water year round. Electric resistance heaters may be installed to provide supplementary heating for the coldest days.They normally utilize much less electric resistance heat and offer significantly higher efficiency than air source heat pumps.
Wood
Some households use wood as their main fuel but even more use it as a supplementary source of heat. Most of these households are outside large urban areas where firewood is usually less expensive than other fuels. The most common approach to wood heating today is a wood stove or high-efficiency fireplace installed in the main living area of the house. If the house is medium-sized and relatively new, this kind of equipment can provide almost all the heat needed.
If you have an existing masonry fireplace, a high-efficiency fireplace insert could be a good option. And many models offer the pleasure of a visible wood fire.
Older or larger houses may need the additional heating power offered by a wood-burning furnace. If your present heating system is a forced air furnace that uses a more costly fuel, you might want to consider an add-on wood furnace. It is installed beside the existing furnace and the duct work is modified so that it can be shared by both furnaces. Combination wood/oil or wood/electric furnaces are options for new or replacement systems. Stoves that burn pellets made from wood or agricultural crops such as corn kernels are also available. Pellets are automatically fed into the burner and the householder simply dials in the required temperature on the thermostat.
When shopping for wood-burning equipment, visit several wood heat retail stores and discuss appliance selection, location and installation with a knowledgeable salesperson.Always buy wood-burning equipment that is certified for safety. It is also preferable to buy equipment that has been certified as meeting the U.S. Environmental Protection Agency (EPA) or Canadian CSA-B415 emission standards. These certified wood-burning appliances produce one-tenth of the chimney emissions and one-third higher efficiency than earlier units.
Outdoor furnace
“Outdoor” wood furnaces or boilers are also on the market. They may appear attractive, because they will burn low cost material you would not think of putting in an indoor appliance and can burn for long periods between refueling. However, they can be low on efficiency and high on emissions.
Solar energy
Like wood, solar energy is a renewable resource. Solar heating does not involve the combustion of fuels, so it does not produce environmentally-harmful emissions. It can be as simple as south facing windows serving as passive solar collectors. Passive solar heating is free and should be an important consideration in the design of homes. Homes built to high levels of energy efficiency and designed to make the most use of free solar heating can save hundreds of dollars a year on energy bills.
Other energy sources
Residential systems are available to generate electricity from sunlight or wind. In certain situations, such as remote locations, one of these may be the most practical option. In addition, the government is establishing standardized processes and technical requirements which will require electricity distributors to allow customers with qualifying generation equipment to supplement their utility electricity needs with power they generate themselves.
