Home solar energy.

You want your house to face south.  With big picture windows, facing south, to pick up sunlight.  You might need to buy a new house, or do some very heavy duty remodeling if your house faces the wrong way or lacks the necessary picture windows.  This works for me, on a sunny winter day my windows pickup enough warmth from sun that my furnace doesn’t run until the sun goes down.  While the sun is up it pours enough warmth into my house to keep it pleasantly warm all day.  No moving parts, no huge and leaky silicon solar cells, no DC to AC inverters, no battery banks, no deals with the electric company to keep my lights on after sundown. 

 You also want some big eaves to keep the summer sun out while letting the lower winter sun in.  You want your roof in a light color, not black, to ease the load on the air conditioner in the summer.  Here in North America the prevailing winds come out of the west, so you want some windows on the west side to open to let in some breeze.  And about the same amount of window on the east side that opens, so the breeze can blow right thru the house.  Some shade trees to shade the house in the summer are good too.

 Builders might keep these ideas in mind.  They don’t add much, if anything, to the cost of the house at the time it gets built.  They do yield a more comfortable and more energy efficient house.