Image Credit: WFI Industries
One of the most overlooked and effective geothermal technologies is the heat pump. As shown in the diagram above, the technology can be used for heating and cooling and depending on the annual temperature variance from the base earth temperature, annual savings vs. conventional HVAC equipment can be as high as 50% per year. Essentially, these systems use the earth (or water held in the earth) as a heat exchanger, moving heat from one place to another via a working fluid in a closed loop system.
In a heating situation, if the ambient air temperature is 32F (0C) and the earth temperature is 53F (12C) the working fluid will be used to transfer heat from the earth to the interior ambient environment – a 21F (12C) advantage over taking exterior ambient air – and then will use conventional means to heat the air to the desired temperature. In a cooling situation, it’s the reverse taking heat from the interior ambient air and transferring it to the earth. Since most humans don’t wish to live in 53F temperatures, further cooling isn’t generally necessary.
One of the leaders in geothermal heat pumps is Indiana based WFI Industries, manufacturer of the Water Furnace. It would seem over the past few years that WFI has been discovered, take a look at their stock chart from that time frame:
Image Credit: Yahoo Finance
This is clearly a technology with huge benefits, particularly where the climate has significant differences in ambient air temperature between summer and winter conditions. Tweet
