The consequence of cheap energy, is that we will use it.
Its not just about riding a bike instead of a car. Its something integral to our decision-making and prioritization matrices.
I've learned lately how it applies to house design, as I design a cabin on our new property.
You see, its very easy to design a house in a way that looks pretty, then find ways to duct heated or cooled air all over it. Such a process can leave the HVAC folks doing gymnastics, but that's what we pay them for. By contrast, prior to cheap ducted heat, and any air conditioning, house design was much more intelligent.
It is possible to design houses that help heat themselves in the winter and cool themselves in the summer. Its quite an artform. But here's some beginners tips, from the easy retrofit to crazy:
Landscape: Evergreen Trees on the North and West cut wind and reduce winter heat loss. Deiciduous trees on the South permit winter sun entrance, but shade and cool during the summer
Angle: You live at a certain latitude. I will live at 43.5. That means at noon, on the vernal and autumnal equinoxes, the sun will be 43.5 high in the sky. Since the earth wobbles 47.5 through the seasons, the noon height of the sun runs from 19 to 66 degrees. By putting a specific length overhang above my windows, I can allow the low winter sun to penetrate my house, but reflect the hot high summer sun.
Celestories are a row of windows between two layers of roof, offering passive lighting and winter heating through the entire house.
Prevailing wind direction (west around here) can be channeled with rocks and hills and forced into a house, or more effectively, pulled out of a high spot in the house with a negative pressure effect, as with these windcatchers.
Solar radiation on a glass/air-gap/black-surface can generate strong pressure gradients and airflow, allowing you easily exhaust hot summer gas, or inject heated air into your house in the winter (see solar chimney).
And of course ground temperature is always ~55F, handy in a million ways.
These are a tithe of options out there. But the best systems are always the simple, elegant ones, which aren't propped up by a million little motors and sensors. Its easy to fix a system by applying more energy. But that's neither responsible, artful or interesting. We can do better. The better system will eventually pay for itself, assuming energy costs don't rise to European levels. Then it will pay for itself sooner.