Description
Geothermal
Heat Pump System
Geothermal
heat pumps function like conventional heat pumps by using high pressure
refrigerant to capture and move heat between indoors and outdoors. The difference
is that traditional systems collect heat and remove it from outside air.
Geothermal systems, by contrast, circulate heat through long, liquid-filled
pipes buried in the ground.
How a
geothermal heat pump works:
Indoor
heat pumps use a basic refrigeration cycle—evaporation, compression,
condensation, and expansion—to capture heat from the ground and dissipate it to
the ground to heat a home in winter and cool it in summer.
Are
geothermal heat pumps worth the money?
Super
efficient geothermal heat pumps provide clean, quiet heating and cooling while
reducing utility bills by up to 70%. "With this technology, everyone can
sit on top of their lifetime energy supply," said TOH plumbing and heating
experts.
Geothermal
Heating and Cooling
As our
cave-dwelling ancestors discovered long ago, if you go far enough underground,
the temperature of the Earth stays around 50 degrees, no matter how hot or cold
it is outside. So while traditional "air source" heat pumps have
difficulty absorbing heat from the cold winter air or dumping it into hot
summer days, its "ground source" counterparts are relatively easy to
extract and distribute heat through a 50-degree liquid where it is grounded.
circulating in the loop.
Advantages
of geothermal heat pumps:
1. High
efficiency
That's
why geothermal heat pumps can generate nearly 12,000 Btu of cooling or heating
with just 1 kWh of electricity. (To produce the same number of Btus, a standard
heat pump consumes 2.2 kWh on a 95-degree day.) The geothermal system is twice
as efficient as a top-of-the-line air conditioner, nearly 50 percent more
efficient than the best gas furnaces, and works 24/7.
2. Low
noise
Another
advantage is that there is no need for a noisy outdoor fan to move air through
the compressor coil.
3. Long
service life
Geothermal
units only need to pump liquid, so they can be parked indoors, protected from
the weather. Most come with a 10-year warranty, but they can last longer.
4.
Reduce household expenses
Reduce
home heating and cooling bills by 30% to 70%.
5. Lower
your carbon footprint
Reducing
greenhouse gas emissions is equivalent to planting 750 trees or taking two cars
off the road.
Geothermal
Heat Pump Costs and Tax Benefits
Despite
these benefits, 47,000 geothermal units were installed last year. That's a
small problem compared to the roughly 1 million conventional heat pumps sold
over the same period, although ground source heat pumps cost about the same to
purchase.
Here's
the thing: You have to bury a lot of pipes—about 1,500 to 1,800 feet for a
typical 2,000-square-foot house. (Actual lengths should be calculated by an
expert based on the home's optimal heating and cooling loads.) Depending on
soil conditions and the amount of excavation and drilling involved, it can cost
up to $20,000 to install a unit of this size.
For
example, a house on a large lot might be able to use pipes running horizontally
in a 4-foot-deep trench. Homes on small plots or rock ledges may require three
or four holes drilled straight down about 300 feet, a more costly process.
Even
with such a huge front-end investment, the energy consumption of a geothermal
system is so small that the payback period is very short. A study by the Air
Force Institute of Technology calculated that it only takes seven to eight
years on average to pay for itself.
Your
actual break-even point depends on your local utility rates,
excavation/drilling costs, how well insulated your home is, the efficiency of
the model you choose, and the incentives your state or utility offers. A good
installer who understands heating and cooling and local geology will be able to
do these calculations for you.
Current
incentives are limited to the standard $300 tax credit for ENERGY STAR HVAC
units.
And
because plastic ground loops are supposed to last 50 years or more, the payoff
for homeowners and the environment can last for generations.
Can I
retrofit one?
Retrofitting
the ground source system is not difficult, as long as it is feasible to bury
the ground loop. On hot days, the house needs ducts to distribute cool air.
Those same pipes can provide warm air in winter.
Contact
us
If you
need to update your heating and hot water system. Please contact us. We will
give you the most professional guidance and free quotation.
