This home is on the 2013 Solar & Green Building Tour.
Twenty years ago I built a new house with the intent of heating it almost entirely with a wood stove. I installed baseboard electric heat as a back up for when I was out of town. That worked well. But about fifteen years later I decided to upgrade the back-up, replacing the baseboard electric with a gas furnace/forced hot air system. At the same time I installed central A/C. I continued to heat primarily with wood, but decided to no longer get up at night to feed the stove so the gas played a larger role in heating the house. As I reached my late 60’s I tired of carrying in wood every 2-3 days in the coldest weather. I started considering alternatives.
I started with a NYSERDA energy audit. I knew there were tax breaks available for energy upgrades and guessed that I might make savings by replacing some of my windows. It turned out that the auditor, Dan Gibson, did tests that showed that my house was quite tight and well insulated. He calculated my Home Heating Index = 3.7 (Heating BTUs/conditioned area X HDD) based on previous fuel use, which he said was very good. The house is also quite tight, just 1.3 times the Building Airflow Standard. Windows would save little. He did suggest I consider a geothermal system. After he explained what it was I proceeded to investigate it by inviting two contractors to further explain their systems and to give me cost estimates. I chose Marty DeVitt of Thermal Associates (Glens Falls, NY). In addition to the prime contractor I would need someone to dig a hole for me. I had another choice to make.
I had two option. I needed 600’ of underground pipe to warm or cool the water that passed through it into the geothermal compressors. I could dig two 300’ wells or a 600’ looping trench 3-4’ deep, (the contractor I chose insisted that even 3’ was sufficient). Comparing the prices of a well digger and a local excavator, I chose the latter option, (I have sufficient land for such a trench).
The NYSERDA audit probably took place in the spring of 2010. By August the geothermal system was installed and working. No problems were encountered. Air conditioning worked as needed. During the heating season the temperature maintained a constant 67 degrees even in the face of some very cold days. At the same time I occasionally used a small gas stove for esthetic reasons. I continued to use the wood stove most evenings for the same reason but never using more than 2-3 pieces of wood at a time. After the heating season I recalculated my Home Heating Index = 2.1 (an excellent rating). This assumes I used the same amount of propane for hot water and cooking as before. This is difficult to confirm because the geothermal heat pump also contributes to my hot water. The 2.1 means I cut my purchased/hauled BTUs by about 40%, with a lot less wood carrying, and with the PV will insulate our heating energy costs as well.
I would like to have lowered the overnight thermostat five degrees, but was advised not to by the geothermal contractor. He explained that when the thermostat was raised in the morning the system would use its electric heater back up as it sensed a sharp differential between the thermostat and actual temperatures, (this same system kicks in when the temperature drops suddenly and the geothermal cannot keep up. In my case this didn’t happen often). “Pick your ideal temperature and leave it there” advised the contractor. The only time when I do not do this is when I leave the house for a week or more. When I return I try to raise the temperature with the wood and gas stoves.
Geothermal uses quite a bit of electricity instead of propane or wood to heat my house. It is essentially a large compressor like a freezer. In part to deal with this I decided to investigate solar electric generation.
As my house faces south with no trees shading it I was a good candidate for that. I invited Olya Prevo of Alteris Renewables (now Real Goods Solar), who is associated with an electrician I know and trust to make a proposal. She did a very careful study and offered several proposals: one using roof panels only that would provide 35-40% of my annual need. One that would add free standing panels that could provide 100% of my annual need. The former offered a payback in 8-9 years. The latter in 18 years. I chose the more modest proposal which would involve 27 roof mounted panels and connect into the power grid so that I could return to the grid peak power that I did not need at that particular point in time. I could then recover that power when I needed more than I was generating.
There was a delay in beginning the project because panels were unavailable. Finally the work was finished in April ’11. On average it has produced slightly more power than predicted; I project I should produce 5770 kWh the first year.
Results to date have been about what I expected though not entirely quantifiable as mentioned above. I don’t plan to make any more improvements at this time. I used home equity loans to pay for this and it is nearly paid off.
My wife and I are retired teachers and we live in this house I built on 30 acres. I used to be part owner of a u-pick strawberry farm. Now I have a modest vegetable garden, enjoy my house and travel when we can. I can be reached through the Member email.