I wouldn't expect you could just one day say "All buildings will be upgraded, no matter what."The part where every building under goes significant renovation. How is that paid for. Come on man? Stop playing
I think for commercial buildings you increase property tax a little for each item not upgraded and give them a tax break once they've achieved all the target upgrades.
For government buildings you just start chipping away. Start where you can both make the biggest impact and where you're losing the most money due to inefficiency.
For residential give tax incentives for upgrading specific items. After a given set of time charge some additional property tax for items that are not upgraded.
But I've got one issue here. I love, LOVE, my natural gas appliances. My tankless water heater is a big one. Electric tankless heaters just don't work as well. Same for my stove top, you can pry my gas burners from my cold dead hands.
