It looks like there are (at least) two people posting, and their requirements would be very differently met.
One lives in an area in Texas where the avg Janurary temperature is 49.3 F degrees,
...and the other lives in Rochester, MN, where the average January high temperature is 20 F and the average low temperature is 8 F.
You both will be flailing in the dark if you don't do a heat balance before you begin.
And if you're going solar, you'll need to do a solar analysis, too.
It's ironic, but to design a heating system for fossil fuel is easy, but the fuel is expensive. To design a system for low temperature heating is expensive (in terms of equipment and in terms of the time spent analyzing the heat load and how you can meet it with renewable... but the heating is very cheap.
But any way you slice it, if you want to go renewable, insulate, insulate, insulate!
Just ask someone who did it... ask randen.
-AC