Help with building a solar sand heater

[Alexlikesfreeheat]

Hi, new member here looking for help.
I would like to set up a sand based solar heater to keep my garage warm over winter.
I was looking at two 550w panels put in series. Max power voltage on the panels is 41.9v and max current is 13.1A.
Inside a steel barrel filled with sand would be a Kanthal A1 coil.
What should be the resistance of the coil in the sand? A quick Ohm’s law calculation would suggest 3.2 ohms which for 16g (0.33ohms/foot) would be about 10’ of wire.

Also how do the panels directly connect to the coil in a safe manner? I imagine using some sort of cutoff switch in case temp gets too high.
I read that a bank of capacitors should be used to store and then quickly discharge into the coil for maximum efficiency but how much better would it be than just letting DC flow to the coil?

Thanks

 

[Solarcabin Channel]

How many sqft is the garage and is it insulated?

Why do you need it heated or at what time of day?

 

[Alexlikesfreeheat]

How many sqft is the garage and is it insulated?

Why do you need it heated or at what time of day?

Hi! It’s about 450sqft and yes insulated but not the garage door. I would like it kept comfortable all day and night and keep things from freezing…about 10c or 50f.

 

[Solarcabin Channel]

A 500 watt radiant heater like the oil filled or quartz with a thermostat set on low or a timer might be better for that.

They sell the quartz garage heaters on Amazon and I use a small 250 watt for a dump load in my cabin.

Any element type sand heater is going to require higher watts than your panels produce I think.