International News
“ GEOGRID ” HELPS CUT ENERGY BILLS
US community is using geothermal energy to keep homes
A warm in the winter and cool in the summer , with exceptional results in terms of costs and the environment .
A planned community in Austin , Texas , has harnessed the power of geothermal energy to slash homeowners ’ energy costs and carbon emissions .
The challenge being : residential buildings account for about 22 % of the US ’ s energy consumption ( according to the US Energy Information Administration ), and more than half of that goes toward heating and cooling systems . These are typically powered by natural gas or electricity , which is usually generated by gas or another fossil fuel , contributing towards a significant share of the nation ’ s carbon emissions .
GEOTHERMAL ENERGY While the temperature on Earth ’ s surface varies wildly with the weather , seasons , and location , that ’ s not the case below the surface . Dig about 10 feet down almost anywhere , and the temperature will be about 54 degrees Fahrenheit . Drill farther down , and it gets even warmer .
All 200 houses in Austin ’ s Whisper Valley development are equipped with geothermal heat pumps that take advantage of Earth ’ s consistent below-ground temperature to provide heat in the winter and cool air in the summer , eliminating the need for fossil fuel-powered systems .
HOW IT WORKS Prior to building the homes , developer EcoSmart Solutions drilled holes into the ground and ran pipes down into them and back out . The homes themselves contain geothermal heat pumps , powered by solar-generated electricity , to circulate water through these pipes .
In the winter when the temperature below ground is warmer than the surface temperature the pumps pull up heat from underground and warm the air in the home . The opposite happens in the summer - heat from the warm air is sunk into the water and then pumped underground to cool it . The cooler water is then brought up to lower the temperature in the house .
THE NEXT LEVEL While geothermal heat pumps are typically used for individual homes , all of the underground pipes in Whisper Valley are connected to a shared “ GeoGrid .” This system includes a pump house that manages the flow of water throughout the neighbourhood using monitoring and control systems . There are also cooling towers to help offset extra heat in the hot Texan summers .
EcoSmart Solutions
Because the homes all sh are this GeoGrid , residents don ’ t have to worry about being without air conditioning even if their personal system goes down — they can just tap into the grid . If a home needs more heating or cooling than its individual system can provide , it can get that from the GeoGrid , too .
ENERGY SAVINGS In addition to the geothermal heat pumps , all of the homes in Whisper Valley have solar panels - the price of those is built into the closing cost of each house , according to David Currie , EcoSmart Solutions ’ community relations manager .
Greg Wolfson , EcoSmart Solutions ’ CTO , noted that the two technologies have cut some Whisper Valley residents ’ energy bills down to just USD1 per month , though it ’ s not clear if that ’ s a consistent rate throughout the year or a rare occurrence .
At least some of the money residents save on their energy bills is offset by a USD40 to 80 monthly service fee for the GeoGrid , though .
“ To keep the GeoGrid running at top efficiency , a monthly geothermal service assessment covers all on-going operational costs , warranty , service and maintenance to the system ,” reads the community ’ s FAQ document .
THE BIG PICTURE Even if Whisper Valley residents are simply replacing a gas bill with a monthly service fee ( and the cost of solar panels ), their use of geothermal heat pumps and solar panels instead of fossil fuels is still a win for the environment .
Article Source : BigThink RACA
A diagram showing how cool air is created by a geothermal heat pump .
www . hvacronline . co . za RACA Journal I June 2022 13