Yes, you can drill for free energy in your own backyard, without fracking or contributing in the slightest to your carbon footprint, by sinking a geothermal well. This technology enables you to tap into the earth to provide heating in the winter and cooling in the summer. Outdoor temperatures change with the seasons but below ground, they remain steady. About four feet below grade (in eastern Massachusetts), temperatures remain constant year-round, around 50 – 55 degrees Fahrenheit. A geothermal system leverages this temperature differential by circulating water below ground in order to heat (or cool) it, relative to the surface temperature, in order to furnish virtually free energy. This energy can be used for heating, cooling or for hot water.
The pipes that make up this circulating system can be installed either vertically or horizontally. This is often determined by the location of the site. In an urban site, the only option is often vertical, and we have drilled as deep as 1500’ in order to obtain the capacity needed to achieve our goals. It is worth noting here that for every 100’ of vertical depth, there is an increase in temperature of about one degree.
During cold weather, the fluid circulating through the well absorbs heat from the ground and carries it into the living space. There, a heat pump compresses the fluid to a higher temperature and circulates it through the area, operating effectively as an air conditioner in reverse. In the summertime, the cooling system pulls heat from the building into the system, which it then circulates back through the well, dispersing the acquired heat below grade.
These fluid circulation systems can be closed or open. HVAC systems are usually closed, meaning that the fluid within them is recirculated. Hot water systems are open, the actual water coming out of the tap is itself circulated into the well.
Unlike conventional HVAC systems, geothermal does not burn fossil fuels to heat or cool. Instead, they transmit the earth’s relative heat, or cold, into the living space. The only operating cost is for the power needed to operate the system’s mechanicals – – the compressors, fans, and water pumps. That said, the upfront cost of drilling wells is considerable and is generally feasible only when there is high volume demand for heat or hot water in the building. For this reason, S & H has generally performed these installations for commercial or institutional clients.