How to build a movable passive solar heat sink?
Kokodad
| Posted in PassivHaus on
My wife & I are remodeling a house to accomodate a 133 inch long dining table when fully expanded. Most of the time the table is closed to a 60 inch diameter. We will install a south facing window approx. 7 ft. long x 4 ft. high. Except for when the table is fully expanded (1% of the time), we could have a passive solar heat sink inside the room near the window, but need to move it to accommodate the table when fully expanded. Have been thinking of something water filled. We could install a faucet & drain in the room. A movable sink would also allow it to be unused during the summer.
Any ideas?
Thanks, Robert
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Replies
Robert,
It would be useful to know your geographical location or climate. Some parts of the country, like Colorado or New Mexico, receive useful amounts of sunshine during the heating season. Others, like Vermont and upstate New York, do not.
Concerning your proposal:
1. I wouldn't do it. The amount of heat that could be gathered by this device is unlikely to be worth the investment required to manufacture and install the device.
2. In the 1970s, many owner/builders experimented with water-filled heat storage devices. Virtually all have been dismantled and removed, for the following reasons:
a. They leak.
b. They take up useful indoor space.
c. The block views to the south.
d. They reduce the amount of light entering the home.
e. They don't gather enough useful heat to justify themselves.
3. To answer your question: Yes, you could build such a device. It is technically possible. Remember, though: by definition, thermal mass is heavy. Providing a lot of thermal mass in a movable device will be an engineering challenge.
Martin -- Thanks. Your assessment that it isn't worth it is well taken and most likely what we will do - nothing. We live in Flagstaff, AZ at 7,000 ft. elev. Relitively speaking, lots of sunshine, but cold in the winter.
Robert
I am currently thinking the same question. Another thought I had besides the water heat sink would be to have a table with a dark stone top. Anybody have thoughts on this idea?
Huge thick soapstone slab, nice. You can shape it with carbide wood working tools and build it yourself. If you are on a slab, the weight would not matter. Build a beefy base for this table for sure.
How about radiant floor heating? The unheated water pipes in the summer would act as a heat sink (water is more efficient at thermal battery than stone by a factor).