My solar PV system was one the reasons I went ahead and ripped out the gas furnace and put in a cold climate heat pump. No amount of solar generation lowered the gas bill, but with the heat pump that is yet another bill that is paid for largely by the panels on the roof. The continued rising costs of gas was another incentive to remove the low efficiency contractor grade gas furnace. In the USA we were also able to take advantage of the tax credit to pay for part of the heat pump installation before trump did away with the credit.

Can I ask what fuel you're using to heat your house now? Also do you have AC for cooling in your house already?