Winter in the Earthship (not quite)

We didn't make it into the building this fall. Between Ruth's cancer and Liam's death we fell short, both emotionally and practically, on a number of key projects. We both took new jobs and that has been a (mostly positive, but still "mixed") blessing. Up here, even a 7 hour a day job sets you on the road in the dark and gets you home in the dark in December. This winter has been exceptionally cold too, at least compared to the last six or seven, with December temperatures often falling below zero (f) and staying for days. We expect some of this in January but this year we got two months of bitter cold instead of one.
The up side is that we got to test the thermal mass of the building without any added input*. Despite several days and many nights well below zero (f) the temperature in the building has never dipped below 24 (f). I sat down there one day, -28 (f) outside, 27 inside, realizing that I had almost 50 degrees difference. Then I noticed that the sliding glass door (which will open into the greenhouse when the greenhouse is built) hasn't been finished or even sealed.

The old (1904) house has a fuel oil (diesel for those in warm climates) furnace that is only about 15 years old. While I deeply hate buring fossil fuel for heat that is what we've got and I don't see a practical conversion at this time. Between the price of the oil and the periodic and untraceable breakdowns with this furnace I am even more adamant about not spending another winter in this house.
The house was built for a coal furnace (the "coal room" is still intact in the basement - I use it as a sandblast booth). The original occupants expected to wear thermal underware all winter, to bundle in sox, sweaters, and several layers of clothing, and to add mittens, boots and coats to go outside. They used copious numbers of quilts at night. Someone had to get up a couple hours before everyone else and make a fire, heat water (thaw, if frozen), etc.
Our expectations are quite different now. Unrealistic, I think, or at least unsustainable. We will, I suspect, slowly switch over to electric heat, but much of this will be generated by burning coal. The coal industry advertises that we have 250 years worth of coal now, but if that is 250 years at current usage, and our usage will quintuple as we switch away from oil to coal, we are looking at 100 years or less, all the while adding a staggering amount of CO2 to the atmosphere.

Our jersey gets a little pissy when the barn is -15 (f) and milking become a trial for both of us. In seeing that the temperature in the sheltered building stays so close to freezing without anybody breathing in there it occurs to us that an earth-sheltered barn would be a pretty good idea. I'm also spending a lot of electricity keeping water liquid for the livestock, and, if respiration would be enough to keep the interior at 33 (f) or above I wouldn't need a water heater at all.

While plans are still being finalized, we will start digging for an earthsheltered barn this spring. The second floor, a hay loft basically, may well be a greenhouse, we'll see.

This last summer my boss put in a commercial heat pump system of a style that is becoming popular out here. A 10' deep by 5' wide trench is dug through the yard and PEX pipe is coiled at the bottom of the trench with the ends run through the basement wall. His application uses several seperate runs of PEX. A water/glycol mix is pumped through the tubing picking up heat in the winter and leaving heat in the summer. A heat compressor/evaporator unit in the house strips calories and heats air that is blown through the existing duct system. He got a true test this last month and figure that in the subzero weather he has been spending about $8 per day to heat his large, old farmhouse.


*Caveat: Almost no added input... Marna brought us a little cast iron box stove that we installed at Thanksgiving and I have set a fire in it maybe six times since. We'll sit by the fire and talk about the house for a couple of hours and let it go out. The stove serves as radiant heat but does not heat the air very much, at least it hasn't in the short times we've run it. I assume that the calories are being stored in the nearby concrete. I have been playing with a 12v computer fan for forced outside air but have not drilled the box yet for a permanent connection to the stove. I'm looking for a cast iron toilet flange as the 4" drain pipe will fit the 4" flexible venting tube perfectly and can be bolted to the side of the box stove. The fan, a little underpowered, runs off a car battery that is charged by a 15wt solar panel. The panel sits on the roof and is covered with snow occasionally, but nothing is running off it right now besides the fan.

FYI:
http://www.blackhawk-studios.org/earthship/
This link is much more eaisily updated and is likely to have more current information. Google has, well, issues with security. I feel for them, I really do, but it makes uploading to this site much more difficult than uploading to my own.