Gross solar-to-loss ratio calculator

A ratio above 100% is possible in a seasonal sum but cannot prove every hour is heated by solar.

Units

F_{\text{gross}} = \frac{100 \times Q_{\text{solar}}}{Q_{\text{loss}}}

Calculator

Enter the values you know and leave one box empty. Calculate finds the empty one, the result or any input.

Given

F_{\text{gross}} = \frac{100 \times 48{,}000{,}000}{66{,}000{,}000} \approx 72.727

Symbol	Meaning	Unit
$F_{\text{gross}}$	gross energy ratio; not the delivered heating fraction	%
$Q_{\text{solar}}$	solar gains over period	Btu
$Q_{\text{loss}}$	calculated losses over same period	Btu

Symbol	Meaning	Unit
$F_{\text{gross}}$	gross energy ratio	%
$Q_{\text{solar}}$	solar gains over period	kWh
$Q_{\text{loss}}$	calculated losses over same period	kWh

Results are estimates for study and screening. Check the inputs, units and assumptions before you use them for design, billing or contract decisions.