An Air-Source Vs. A Ground-Source Heat Pump

What if you could heat your home without using a fossil fuel? What if you did not have to draw electricity from the grid? What if you only needed one piece of machinery? You can achieve all of these objectives simply by using a heat pump in your home. If green heating is your goal, you have two main types of heat pumps to choose from: air-source  and ground-source.

How Does a Heat Pump Work?

Heat pumps use one set of fins, known as evaporator coils, to absorb heat from their surroundings. A second set of fins, known as condenser coils, expel this heat. To cool your home, you place the evaporator coils on the inside and the condenser coils on the outside. A heat pump allows you to reverse the function of your coils so that the coils on the outside absorb heat and the ones on the inside expel heat. The difference between the two types of heat pumps hinges on where the outside coils are located. 

Air-Source Heat Pump

An air-source heat pump is virtually identical to an air conditioner in that it will have a set of coils located at ground level on the outside of your house. These coils heat your home by extracting heat from the surrounding air. In this way, an air-source heat pump can achieve efficiency ratings of up to 250%. In other words, for every unit of electricity the pump uses, it will generate 2.5 units of heat. By using solar panels or wind turbines to generate electricity, you can heat and cool your home independent of any outside utility. The drawback of an air-source heat pump is that the colder it gets outside, the less efficient your pump will be. Also, the hotter it gets outside, the harder it is for an AC unit or heat pump to force hot air into the outside air. 

Ground-Source Heat Pump

If you dig down 5-10 feet below the surface, you will find that ground temperatures remain a constant 50˚F year round.  By burying specially designed coils underground, you can tap into these moderate temperatures to reach efficiency levels of up to 600%. You will also be able to use the earth as a heat sink to expel heat from your home on a hot day, and as a heat reserve to pump warm air into your home in the dead of winter. 

Because of the need to bury coils underground, ground-source heat pumps are considerably more expensive than their air-source counterparts, but because you can eliminate your operating costs by powering your heat pump with solar panels, you may be able to offset the high installation and/or financing costs. On the other hand, whether you use an air-source or a ground-source heat pump, you can have the peace of mind that you are conditioning the air in your home in an environmentally friendly way. For more information, contact a professional like those at D & R Service Inc.