

And buy them according and after you’ve done everything possible to insulate your house, whether in the colder or warmer climates.
In the USA there are silly rules that you can only get 120% capacity of your last years worth grid consumption as solar installed. So if one were to follow your advice and do all the energy efficient improvement prior to solar, then you would be restricted to getting a much smaller array. I understand why they have the rule, but its easy to circumvent by just having artificially oversized consumption for a year in your house, and you can then get the larger array you want before then doing all the energy improvements post-array installation.
I’ll say generally speaking in most places it isn’t, however, once you go solar, you may increase your electricity usage as you move away from carbon based energy. Before solar we had natural gas furnace heating and two gasoline cars. Now we have two EVs and a cold climate heat pump with zero natural gas and zero gasoline consumption. So I wanted the larger solar capacity to cover the increases in electricity we knew we’d have.
Its worked out pretty well. We have fairly large electricity bills ($400ish) in Jan and Feb, a small bill in March, and usually a tiny bill (under $10) in April. Then no bills for the rest of the year. Also keep in mind that is TOTAL energy costs, no gas or gasoline bought anymore.