Back in the 70's my brother had designed a water wall for installation in a house.The wall was was passive solar energy collector and storage system.
No moving parts. Now the house was built with good insulation also. He built some of the houses in Virginia and documented all the data and the houses are still there today.

Now the place in VA where the houses are has the same sunlight (degree days) and temperature as Louisville, KY.
1250 sq ft, 3 bedroom ranch cost $75 per year to heat. Think what that would do to the coal industry, utility industry, and oil and natural gas industry if a lot of folks used it. If suddenly 20 percent of the house used it I guess the impact on large industries could throw us in a severe recession or worse.

Then ...Jimmy Carter lost the election and Reagan went the other direction My brother closed up shop the month after.
Yes politics touches everything and I mean everything. No one has figured out a way to own the sunlight. Maybe one day the Government will tax sunlight..not an absurd proposition when you think about what is taxed..property being one. It's all about the money and I guess there is nothing wrong with that.

There are ways to passively cool a house also.
A solar hot water heater is definately a no brainer.

All this not to be confused with solar cells.

Wow. maybe this post dies not belong here