Heat Pumps for your Home

Next to transportation, heating and hot water represent the largest use of energy in the state. Over 75% of home energy use is for heating and hot water in Massachusetts. A typical household in Stow spends over $1,500 per year using fuel oil or natural gas for heat and hot water. The best first step to reduce your energy costs and fuel use is to investigate energy efficiency measures such as insulation and sealing the “envelope” of your home from drafts. Consider the free home energy audit offered through Hudson Light & Power to find out which energy efficiency measures are right for your home.

Another way to reduce energy use and cost, while protecting the environment, is with heat pumps. Heat pumps may sound exotic but they run on same principle at work in your refrigerator and air conditioner. A heat pump “absorbs” heat from a cold space and releases it to a warmer one. The use of heat pumps for home heating and hot water has been common for a number of years in other regions and countries. Over the last several years, improvements in the technology have made heat pumps a good choice for colder regions, like Massachusetts.

Most heat pumps run on electricity. But unlike conventional electric heating and hot water systems, the electricity is not used to directly heat a “resistive” heating element, such as used in electric baseboard heating or the heating element in a hot water heater. Rather, with a heat pump, electricity is used to power the “pump,” which moves heat instead of generating heat directly. This results in efficiencies up to five times that of conventional electric heating. In other words, heat pumps can deliver as much as five times the heat, per unit of electricity, as conventional resistive heating.

There are many different kinds of heat pumps for space heating and hot water. For space heating, there are air-to-air, water source, and geothermal heat pumps, which differ in the source of outside heat. In general, water source and geothermal heat pumps are more expensive but more efficient that air source heat pumps. A popular form of heat pump for space heating and cooling is the “ductless mini-split.” These are air source heat pumps that are installed without the need for ducts and provide both heating and air conditioning. Mini-splits can be a good choice for an addition or an area of the house that is a problem to heat or cool. Heat pumps can also be integrated with the ductwork of an existing heating system. If your hot water tank is in the basement along with a furnace, there will be “waste heat” from the furnace that makes this location particularly well suited for a heat pump hot water tank. A good time to look into this is when you need to replace existing heating or hot water systems or are considering a home addition. Contact an HVAC contractor to see what type of heat pump system is right for your house.

In Stow we are fortunate to have both low cost and clean electricity. Our electric provider, Hudson Light & Power, has one of the lowest electric rates in the state, and 80% of its electricity is generated from sources that emit no greenhouse gas. The result is that heat pumps not only cost much less to run than conventional electric heating and hot water, they are also more economical than fuel oil or natural gas. From an environmental perspective, using a heat pump in Stow produces less than a fifth of the greenhouse gas from burning fuel oil and less than a quarter of the greenhouse gas from burning natural gas for heat and hot water. Hudson Light & Power also offers substantial rebates for both heat pump water heaters and space heaters. See their web site (www.hudsonlight.com) for details.