The fluctuating nature of air temperatures can adversely affect the performance of a heat pump. The problem is that as the temperature climbs, it gets harder for your heat pump to force heat into the outside air as it cools your home. Furthermore, as the temperature falls, it gets harder for your system to pull heat from the outside air to heat your home. Thus, if you like having one piece of equipment to both heat and cool your home, but you want the most efficient system on the market, you need to trade in your air-force heat pump in favor of a ground-source model. 

The Difference between the Two Systems

While you can force heat into the outside air to cool your home and extract heat to warm your home up, the air is not the only substance you can use for these purposes. The ground will serve as an endless heat sink during the summer, so you can use it again and again to cool the refrigerant running through your coils. During the winter, the temperature of the earth will remain much more consistent than the air temperature will be, so it is a reliable source of heat for your home. In fact, the ground will remain between 35–45 degrees year round at a depth of 10–15 feet. By using a specially designed set of coils, you can tap into these consistent temperatures and boost the performance of your heat pump. 

How Much More Efficient Is a Ground-Source Heat Pump?

When deciding between an air-source and a ground-source heat pump, efficiency is an important consideration. On a good day, an air-source heat pump can be as much as 250% efficient; in other words, it will move 2.5 units of heat for every unit of electricity it uses. On a bad day, this efficiency falls to 175%. By way of contrast, a ground-source heat pump will achieve up to 600% efficiency on a good day and at least 300% efficiency on a bad day. Thus, you can vastly decrease your heating and cooling costs by using a ground-source heat pump. 

Whether you choose an air-source or a ground-source heat pump, you will most likely have to finance your system. Thus, your main concern should be whether your financing costs are lower than the amount of money you stand to save with the ground-source heat pump. To answer this question you will need to have an HVAC technician like Fred's Plumbing & Heating Boilers analyze your system and estimate the amount of money you stand to save. In the end, a ground-source pump is at the very least an option worth looking into.