|Project by summerfi||posted 12-19-2013 11:12 PM||2523 views||18 times favorited||37 comments|
I live in a cold climate, and heating my workshop in the winter can be an expensive problem. We’re not allowed to heat with wood where I live due to air quality restrictions. The options are electric or natural gas. I have an overhead natural gas heater in my shop, but it adds a chunk to my utility bill and is also somewhat noisy. Fortunately, the front of my shop faces due south. That got me to thinking maybe I should try to capture some of nature’s free energy.
After researching several solar heating options, I settled on a design similar to this because of it’s simplicity and low cost. The design couldn’t be simpler. It is totally passive, consisting of a transparent panel installed in front of your insulated garage door. The door is raised on sunny days to allow sunshine and radiant heat to come in, and closed at night or on cloudy days to trap the heat inside.
Here are pictures of my version of this heater installed on my shop.
The heater consists of four 48” wide x 8’ tall removable panels. The frame is made of 1x pine that I cut on my small sawmill. The transparent material is clear polycarbonate corrugated panels like are used on greenhouses and patio roofs. The only other materials are some black spray paint, clear caulking, foam weatherstripping, and screws. The 26” wide polycarbonate panels are available from Lowes for $21.62 each. In total, I have less than $200 in the project. In addition, I had previously installed 1 1/2 inches of foil-backed polyisocyanurate foam insulation on the inside of my garage door.
So how does it work? Since installing the heater last Sunday, we’ve had three sunny days. If the sun shines all day, and I open the garage door in the morning, by mid-afternoon the inside temperature has proven to reach 30 to 35 degrees higher than the outside temperature. Right now the temperature outdoors is 25 degrees, and inside my shop it is a pleasant 60 degrees. I’ve not turned the gas heater on all day. The highest temperature I’ve achieved so far was 70 degrees on a day when the high outside temperature was in the 40’s. I anticipate that as days get longer and warmer, I will have to keep the garage door partially closed, or open it only for a portion of the day, to keep it from getting too warm inside for comfortable working.
This is a picture from inside the shop looking out.
In addition to warming the shop, this 8’ x 16’ “picture window” also lets in a lot of light. This should help save on electricity too. Not only does the solar heater warm the body, but it also helps warm the spirits. The bright working environment is much more pleasant to be in during cold winter days than a closed up shop.
While I’ve had this in operation for less than a week, the results I’ve seen so far make me think it’s going to be a big success. When Spring comes, I’ll simply remove the four panels and store them away. They are made to be light and easily moved, and they can be installed or taken down in about 15 minutes.
-- Bob, Missoula, MT -- "Of all the tools I own, my favorite is a good sharp pocket knife." - My Dad