Page 10 - Advanced Technology for Energy and Water Saving

Presented with the challenge of heating and cooling e‘ciently, some

of the energy-e‘cient options include geothermal, along with more

“renewable” sources, such as biomass/wood heat and electric heat

pumps. Let’s look at the pros and cons of four HVAC systems:

© GEOTHERMAL HEATING

AND COOLING

GEOTHERMAL HEAT PUMP (GHP) uses refrigerant-filled underground piping loops,
installed horizontally or vertically, to exchange heat with the earth. These systems
work well in both warm and cold climates. A good GHP is able to move three to five
times more energy than it consumes. Models are available for use with forced-air
A hydronic distribution systems. While
or
the hydronic models don’t get water as hot as a
conventional boiler (122°F, compared to 150°F or
more) their low temperature output is a perfect
match for radiant floor heat.
The primary limitation to a geothermal system
is its relatively high installation cost—often
double what a similar on-demand hot water
system might cost. After installation, however,
the only real cost is running the electrical pumps.
In theory, you could combine a solar PV system
with geothermal heating/cooling and have zero
operational costs.
Another consideration, of course, is the lifespan CREDIT: RUSS PARRISH
of the system. While estimates vary, the consensus
seems to be that the indoor components of a
geothermal system last 15-25 years, while you Natural Warmth. Pools large and small can be efficiently
can rely on the underground loop for 50 years. heated with geothermal systems
Keep in mind that even if you spend $30,000 on a geothermal installation and it lasts 25
years, replacing the indoor components at that time will probably be less than half your
original investment.
Geothermal also protects you from potential price shocks associated with fossil fuels.
Natural gas prices, while still relatively low, are on the rise, and the extraction process
known as fracking has come under increasing scrutiny. There is no guarantee that future
prices will remain stable. For a primer on geothermal heating, download this PDF from
NV Energy.

10ADVANCED TECHNOLOGY FOR ENERGY AND WATER CONSERVATION