Severe freezes occur only occasionally in winter, with temperatures below −10 °C (14°F) being very uncommon, and temperatures below freezing uncommon in many coastal areas.
I note the last line – 14°F) is « very uncommon » as this corresponds to your own input minimum…
So your minima is (at least) "uncommon"..
(even if your maxima is "demanding" !)
So although your above post addresses a panel question, excuse me for ignoring the panel business, since my first reaction would be to compare your heating requirement in more detail, against the reference MO GH, to put things into some sort of perspective.
Once that is done, you could then examine improvements (as they suggest...) to adapt the MO GH design to meet your requirement of 65°F.
Again, not wanting to be a bore, IMO the required top-up heat would NOT come from a solar panel in any case, but from another heat source than solar (such as gas or electric heating, generator, lighting etc.).
So (finally...) turning to your heating requirement, of 56 kW of heat.
(apologies for using metric again…) (it’s become a bad habit…)
your temperature difference is 65°F – 14°F
that is 18.3 (say 19°C) minus –10°C
giving a TD of 29 kelvin
56 kW ÷1.163 = 48,150 kcal
÷ 29 = 1660 liters of water
(= 438 USG, or 365 imperial gallons)
crosschecking : from your spreadsheet:
power = 193,244 BTU ÷ 51°F = 3789 lbs of water
divided by 8, = 473 USG.
(The 35 gallon difference in the USG is because I calculated my kelvins for 19°C, not for 18.3 °C, which is your 65°F requirement).
Therefore, to recap,
- the Missouri Greenhouse could almost meet your requirements, as-is, using the same approach but perhaps with the additional insulation that they forgot to install on the backwall...
- You will most likely need additional heating to hit the 65°F requirement.
- This would come from another heating source than solar (gas, electric, generator etc.)
- paid for by the money you would save by not constructing panels.
In addition, without getting involved in your business plan, if as you say U are likely to have to change site at some time, and your GH is presumably knock-down, not having to transport and re-erect panels would no doubt be a considerable saving.
Good luck with the rest of your thinking !
__________________(1) "Heat goes from hot to cold, there is no directional bias"
(2) It's wrote, "voilà" unless talking musical instruments...