Yes it is.
Some of the most cost effective solar's are:
* The electric attic fans, dramtically reduce you A/C load.
* Solar H20, if you make them from scratch and or kit and you are plumber and electrican enough to pull it off.
* Proper house orientation, if building from new, 20% of your heating for free if you do it right.
* The old Trombe Wall Passive Heating. Can be done as a retrofit, but maybe better new, and I don't know if anyone has revisited it today with maybe some techno-upgrades. in the lates 70's claims of 50% of you heating could be had from this wall.
Many if not all of these can be done without the Fedzilla benny bucks which is fine with me.
I had an Idea this a.m. a variant of the Trombe Wall that I need to run by my hvac / anything home guru that just might work.....
My parents were looking to retire to New Mexico (my mom’s home state) and were looking at lots of home designs. This was in the late 90s early 00s. Quite a few include some form of Trombe wall. They were seriously considering straw bale with a Trombe wall, but my dad started getting health problems, so they just stayed put.