Winter 2008 Issue of the Finger Lake Sierran
Our New Geothermal Heating and Cooling System
by Annie Koreman, Energy Chair, Finger Lakes Group
We have a 2,200 square foot 100 year old farm house in Trumansburg, New York,
which is 10 miles from Ithaca. Our house has had several additions and many
renovations over the years. During the winter we have kept our home pretty
cool and were heating with a woodstove, a 40 year old oil forced air furnace
and several electric ceramic space heaters. We were using 2 full cords of wood,
350 gallons of oil, and an undetermined amount of electricity, . . . and still
our house was cold.
In August of 2008 we had our new 3.5 ton geothermal heating, A/C, and hot water system installed. Our old furnace was about 85% efficient. Because efficiency really means how many units/BTU's of heat is produced from each unit of energy put in, you could also call it a coefficient of .85. Since geothermal units in the Northeast use energy from under the frost line (or in lower sections of bodies of water) which is a constant 50 degrees Fahrenheit, coefficients greater than 1.00 are possible. Our system heats with a coefficient of 4.50 so it is about 5.3 times as efficient as our old oil burner.
It is difficult to say just how much money we will save because they added
heat ducts to rooms that did not have them before, we will no longer use electric
space heaters, will use our wood-stove less, and we will have our thermostat
way up to 68 when we are home. The system also provides hot water and A/C (we
didn't want A/C, it just comes with it.. .and we did use it in August) which
is difficult to factor in. Of course it will save us money in the long run,
but our payback is immediate since it helps our environment which was our main
reason for doing it. There are estimates that this type of system takes 12
years to pay back. Most of our electricity to run our geothermal system comes
from our solar panels in the back yard which also helps lessen our footprint.
There are several options for geothermal units such as open or closed loop,
vertical wells, and coils just under the frost line. Ours is a closed loop
system with vertical coils sitting on the bottom of our 10' deep 1 acre pond.
Instead of forced air, you can have radiant floor heat, but then you don't
get the A/C. Total costs including excavation work for our system were about
$19,000. Dan Christy from GeoTherm in Tully, New York designed and installed
our system and we are very happy with it.
After a year of operation, we will let you know how much money and energy we saved. Please contact me if you want more information on our system or our experience.