Heating a garage

Hello everyone,

I'm very new to all this but it looks like a very interesting DIY project. I am considering building this to heat my garage in the winter. Would it be possible to hook this up to something like a radiator? Not sure what would be the best fluid to use to ensure it wouldn't freeze over night. Any suggestions/tips are appreciated

Cheers

Hi Chachie.

Using the device to heat a transfer fluid should work well. You could place multiple collectors in series to get pretty much any energy input you wanted, tho unless you're collecting at a lower altitudinal point than your garage you'll need to use a pump. Not that that's really a problem.
A while back I looked into various oils as heat transfer fluids, but can't recall the numbers off the top of my head. It's surprisingly hard to find boiling point data for vegetable oils, but you wouldn't be getting anywhere near them for this application anyway, and smoke points shouldn't be an issue in an anaerobic environment.

I remember that the best oil performance wise was castor oil, but it's expensive. There was one very cheap and common oil which looked like it would work well, maybe sunflower, maybe cannola, something like that. Anti freeze doesn't work as well as you may have been lead to believe, motor oil and similar would be good if you want to pay for it.
No idea on freezing points, but generally the higher the boiling, the lower the freezing, and unless it get very seriously cold where you are there should be something that'll work.

Keep in mind that concentrated solar technology does require direct sunlight. Not so much for the energy content as the optics. So it'll work fine on a clear winter day, but any cloud will kill it.

Hi

How about used motor or gearbox oil. You think that might work ? If so which one would be better ?
Thanks

People do use motor oil, seems an ok option. Not looked into other kinds, but I'd imagine they'd work.

The relevant numbers are; specific heat capacity (how much energy it takes to heat a gram of the stuff one degree, the higher the number the more heat it'll hold at a given temperature), the boiling point (higher the better, you don't want pressure buildup in your system if it starts boiling), the smoke point (things busting into flames is generally not desired), and the cost. Toxicity is probably something to consider as well.

Admin wrote:

The relevant numbers are; specific heat capacity (how much energy it takes to heat a gram of the stuff one degree, the higher the number the more heat it'll hold at a given temperature), the boiling point (higher the better, you don't want pressure buildup in your system if it starts boiling), the smoke point (things busting into flames is generally not desired), and the cost. Toxicity is probably something to consider as well.

Wouldn't water work pretty well, mixed with just enough anti-freeze to keep it from freezing at lowest anticipated temperature? As long as the system was limited so boiling point was not reached. With tank type waterheaters installed in the billions world wide, spare pressure relief values should be trivial to obtain. But then you have to deal with the toxicity of any escaping anti-freeze. Hmmmmmmm. A system that allowed the water to drop into an insulated storage container at night might solve that problem. Then no antifreeze would be needed.