[Bay Area, CA] – Calculating how much solar to get specifically when it comes to converting gas (therms) to electricity (kwh)?

I am in San Jose trying to calculate how much solar I need. I know how to look at PG&E usage, factor in future EVs, etc. But I have a gas furnace and gas water heater and am trying to figure out how to convert that usage to electricity usage for whenever i replace them in the future. They are both 9 years old and the house is too. I am not sure about their efficiency.

My last 12 months gas usage is 229 therms. 1 therm is 29.3 kwh so converting that to kwh is 229 therms * 29.3 = 6709 kwh. Heat pumps are apparently 3x efficient so 6709kwh / 3 = 2236 kwh is how much these appliances will use once converted to heat pumps?

Does this make sense?