[pjc50]

Incremental improvements are the only way. Only you can make the decision as to what's viable for you. How's your insulation? Political engagement matters too: is there anything you'd like to lobby for or against?

I declared solar PV viable for me in Scotland at 56N, due to the available feed-in tariffs, and it's working pretty well. House not so old but the gas heating bill is unpleasantly high.

Don't overlook transport in global warming, it's not just about the house.