I get that if your heart is set on having a heat pump you need a heat pump, and that's the end of all financial consideration.
But how does, say, $10K of heat pump compare to $10K of insulation and better windows/doors/roof, or $10K of solar panels and cheap ultra-low-tech repairable all-electric HVAC, or $10K of some other form of physical investment I'm not aware of?
If you have a perfectly serviceable means of heating that you are happy with, then it's a straightforward cost analysis (cost of consumables for the current heating method vs cost of electricity for the heat pump).
I can only give an example that applies to my situation: previously I burned ~2300l of diesel which cost around 2300EUR for the previous heating season. So the yearly energy consumption is about 24MWh (combustion heat of fuel multiplied by efficiency of the furnace of ~94%).
If I were to install air source heat pump, it would require about 8-9.6MWh (COP =2.5-3) of electricity per year (4000-4800EUR at the current fixed price offering from my electricity supplier of ~500EUR/MWh).
If I were to install a ground source heat pump (COP of 4.5-5.5), expected electricity consumption is between 4.3-5.3 MWh or ~2200-2600EUR/yr.
If I were to power the ground source heat pump using the electricity generated by my solar panels (Latvia currently has 1:1 net billing system, but there is a grid cost of ~50EUR/MWh) the expected yearly heating cost is ~210-260EUR.
At the previous electricity cost of ~100EUR/MWh, air source heat pumps for not-so-well insulated houses might be attractive option- but not at the current prices in Europe.
When I did the calculations this spring, the break even time for heat pump + solar installation was ~8 years (based on fuel and electricity costs at that time).
Right now it's around 4 years (and I might even get ~40% of the investment from a government clean energy incentive programme). However, I have to operate under assumption that a crazy dictator of a neighboring country doesn't decide to invade and wipe my house off the Earth...
Insulation almost always wins during initial construction.
Solar panels probably come in second because they create waste energy that unlocks free EV charging, etc, etc (but you will pay more than $10K for the system), so, thanks to sunk costs, other stuff becomes "free".
Heat pumps are probably the cheapest big bang for the buck upgrade for existing construction (especially if you have to replace your HVAC anyway). Minisplits are often a big win for retrofits of buildings without central air.
All of these things are dominated by labor costs, and we are in the middle of a labor shortage. You are unlikely to find realistic financials unless you get bids and compare with your personal energy rates.
We didn't do any of that.
We just assumed energy prices would continue to explode over time (we were right), and jumped off the inflation carousel by putting in solar and all electric appliances.
Also, we can't get natural gas service, and propane costs 4x per BTU more than natural gas around here. Most electrical appliance upgrades are subsided by the government to make them competitive with natural gas.
That made it a no brainer.
Since then, a bunch of indoor air pollution research showed that natural gas causes asthma, etc, etc. Also, the war in Ukraine started.
So, what are your health, future financial predictability, and engineering economics braincells worth? For us, the answer was "less than the installation cost of the system".
Also, after all they put us through, seeing a -$120 bill from PG&E each month makes me irrationally unhappy. ;-)
A heat pump is 3x more efficient at heating than a resistive electric heater, making it just about a wash with a gas furnace in most markets in terms of sustained cost. The hardware is more expensive, but not THAT much more expensive. When you include installation costs and amortize over a 20 year system life, the overhead is non-zero but quite low (10% or so). If you guess that gas is going to be more expensive in the coming decades where electricity is futureproof, it seems like a good bet to me. Ask me in 20 years.
Lived & owned homes for 20 years in an area where ASHP are standard installs as the climate range meant 100% of normal (outside of freak polar vortex) heating and cooling was covered by the heat pump. Inexpensive part failure is common annually - usually capacitors and fan motors. Usually expensive part or system failures occur around 10-15 years.
I get that if your heart is set on having a heat pump you need a heat pump, and that's the end of all financial consideration.
But how does, say, $10K of heat pump compare to $10K of insulation and better windows/doors/roof, or $10K of solar panels and cheap ultra-low-tech repairable all-electric HVAC, or $10K of some other form of physical investment I'm not aware of?