DIY solar powered heat for my garage studio for next to nothing
Now that cooler fall weather is firmly here and freezing cold winter is around the corner, I’ve been thinking about moving my clay, glazes and tools to the communal heated studios of the Colorado Potters Guild. As a mom to an elementary school age child, however, I love the flexibility of being able to work from home when and where I find free time and schlepping back and forth to the guild is really going to be a downer for me. So, I started a search for an inexpensive heat source for my garage/studio that can be left unattended overnight.
Well, you know how it is when using the internet to research – one link leads to another and all of a sudden, I discovered a gazillion DIY solutions for supplemental heat powered by the sun on a shoe string budget. If I knew we were going to be staying in our current home for awhile, I’d install photovoltaic solar panels on the house and my studio, but it looks like we’ll be moving within 1-2 years.
The photo above is from a project detailed on the Hemmings Motor News Blog and shows how to make a homemade solar convection heater that uses commonly available materials both recycled and readily available for almost 0$ – absolutely less than $100.00 if you have to buy everything.
Project list includes:
- Have to have south facing wall or window that gets direct sun for a good part of the day
- empty clean aluminum cans
- weather proof caulking
- screws and assorted hammers, screw drivers etc.
- black all weather paint (for grills)
- glass or acrylic panels (recycled windows would probably work great)
- dryer vent tubing or other
- insulating panel, foam or batting
- low volume fan
- dryer vent
- metal flashing
While the project does require cutting holes into your wall, this site illustrates a similar set up mounted in a window instead of a wall which requires no cutting of holes into an exterior wall – which is pretty cool because this makes it portable (perfect for apartment/condo dwellers).
So how does it work?
Cool air is pulled in from the bottom inside wall vent and as it’s warmed by the sun in the solar chamber, the heat rises naturally and it expelled back into the same room higher up on the wall – natural convection heating. On sunny days, a 30-50° increase in temperature can be achieved with this system.
The downside of the system is that it only works while the sun is shining, so at night or on overcast days, it won’t really provide heat, so it really only functions as a supplemental heating system. The price is right, however, and here in sunny Colorado it is well worth the effort. If installed in a more temperate climate in the south, supplemental heat wouldn’t be needed at all.
On the website, Instrucables, this project uses window screens instead of aluminum cans and was adapted from a $350.00 solar heat project that Gary Resa author of Build it Solar built for his barn and that was published in The Mother Earth News and Home Power magazines. If you download Gary’s pdf with photos and plans, he provides a graph that looks at outside air temp, solar chamber output, inside temp at different times of the day and night which is incredibly helpful since I want to prevent my clay and glazes from freezing. Even at night it looks like his barn workshop stays above freezing even though the outside temp can get to 10-20° F in the winter where he lives in Montana. His project is also very detailed an provides safety recommendations such as adding metal flashing to vents since most buildings in the US use wood framing.
Here are some photos of similar projects here (I looked for more information about this set up, since the maker of the project claims that enough heat is stored to adequately heat the space overnight, but could find none), here, and here.
A commercial alternative for those of you who aren’t on a budget is made by Cansolair out of Newfoundland, Canada for approximately $2800.00 installed and can heat approximately 1000 square feet of living space.
Visit this website to see Cansolair’s Canadian patent application for design drawings for a better understanding of how this type of passive solar space heating works and for design ideas.
Solarsheat is another commercial option with varying sizes available from $1290 per unit and can be wall or roof mounted. This is the smallest usit – though the company makes larger ones depending on space heat requirements.
This video shows a similar set up as the recycled can solar heat collector, but with 3″ aluminum dryer venting instead of recycled aluminum cans.
This is a longer 16 minute video from Green Power Science who made a solar collector heater using just cardboard, paint and wood and it can be mounted on a wall or roof. The author does advise people to use weather and heat proof materials for a permanently installed unit of your own making.
Pros of solar heat collectors:
- inexpensive to free
- uses solar energy to heat spaces which saves money
- Less dependence on fossil fuels
- not too difficult to make – no special skills needed
- depending on the size, you could heat your whole house or just an outbuilding/shop/garage
- Supplemental heat – doesn’t work well on overcast days and not at all at night
- Not a terribly attractive addition to the house – though some aren’t bad
I showed my husband the plans and we’re going to try to make one. Probably an amalgamation of several plans and we are going to make it with safety in mind.
I will need to add supplemental heat to the garage/studio for overcast days and nighttime, but in my search for solar powered space heaters, I found the following electric heater that should do the trick.
Eco Heaters are high energy efficiency convection heaters that are mounted on a wall and cost about 3¢/hour to operate – If I used it from 10pm – 8am, the cost would be approximately .30/day during the winter months. If I can get a satisfactory result from the DIY solar heater, I’m going to buy one of these and install in in my garage studio – I should only have to operate it at night when the temp is expected to be below freezing. It is also portable, so when we move, I can take it with me.
Meanwhile, my husband and I are going to try making on of these removable storm window solar panel heaters for a south facing window on the main floor of our house just for kicks. The panels are capable of delivering 120° F + of supplemental heat on sunny or partly sunny days and if you have a thermostat installed in your home, the main heat source won’t come on at all until the temperature drops. We have gas forced air as heating for our home and normally program our thermostat to raise the temp to 65°F only between 6am – 9am and then again 4pm – 9pm. During sleeping hours and daytime hours, it’s set at 55°F – the house heats up pretty well during the day due to many south facing windows.
Meanwhile, I’ve loaded a packed kiln for a bisque firing and will have one additional bisque to fire tomorrow which will leave me 5 days to glaze and fire. I imagine I’ll have to press my old manual Paragon into service to get all my work fired in time for the Guild’s sale next weekend.