Heating a home or office can be expensive and the energy required has a lasting impact on our environment. With winter approaching it is a great time to think about our buildings’ heating needs. Luckily for businesses and home owners there are a wide range of strategies available to help limit the costs and impacts. With EAC’s recent office renovation we implemented many of these strategies. Our focus was on reducing the amount of energy we need by improving the insulation and air-tightness of the building. Now we are looking ahead to the next best way to reduce our energy usage. We think the answer is a heat pump.
Heat pumps use energy to transfer heat, the system takes heat from the outside air and brings it inside using the same technology as refrigerator or air conditioner. These technologies rely on the ideal gas law, more specifically the relationship between pressure and temperature (If you are interested in the details Natural Resources Canada has a great explanation here). Heat pumps are able to function effectively in cold weather, which is particularly important in Canada. Even if it was -77C outside the heat pump can effectively warm a house. The reason heat pumps are able to save energy is that the energy required to transfer the heat is less then what is needed to generate heat.
Here at the EAC office we want to install an air-to-water heat pump. The system will connect to our in-floor radiant heating system which uses heated water to warm the floors (and us!). An air-to-water heat pump would heat the water stored in our hot water tank and reduce the need for electricity to heat that water. An air-to-water heat pump is a great fit with our in-floor radiant heating system, since water temperatures in the system do not need to rise very high to effectively heat the building.
There are various types of heat pumps on the market that can help reduce your heating energy usage. One distinction is how they distribute the heat. Some act as point source heating, similar to a wood stove, others connect to ventilation systems in order to spread hot air through a building. Another distinction is where the heat comes from. There are alternatives to air as the source of heat; some heat pumps rely on ground or groundwater to be the heat source. One notable benefit of many heat pumps is that they are reversible, which means the same system that helps heat your house in the winter can help keep it cool in the summer.
This does not mean heat pumps are the solution for every building. Addressing issues of insulation and air sealing is always the first step to reducing your heating needs. However in cases where they are good, fit incentives such as rebate programs can help you make the switch. For more information about heat pumps check out Efficiency Nova Scotia or the Green Building Advisor.
At EAC we’re still in the planning stages. We’re expecting to turn on our heating system fairly soon, including the solar water heating part of our system. If our fundraising goes well, we’ll be able to install an air-to-water heat pump by Sept 2017 and monitor the savings (and relish the cost and emissions savings it will bring).