Home Heating Efficiency
If your numbers are accurate (that seems like a shockingly low price per therm for 2020):
10.57 cents buys you 13,989.2 BTU at a COP of 4.1 in the heat pump.
14.14 cents buys you 96,700 btu in the furnace, or 95,000 in the boiler.
A dollar buys you 132,348 BTU at the heat pump, or 671,852 at the boiler, or 683,875 at the furnace (&quot;heating fuel cost&quot;, ignoring the fact that all of them use additional electricity to move the heat around)
At those prices, you want to use the heat pump for cooling only, unless you have excess electricity to burn (Solar panels and no buy-back, just offset) or the two gas sources can't keep up on a cold day.