In any control system that is functioning properly, the methods used to control a signal won’t be correlated with the signal they’re controlling.
Worse, there will be several variables that DO show relationships, and may give the wrong impression. You’re looking at variables A, B, C, and D. You see that when A goes up, so does B. When A goes down, C goes up. D never changes and isn’t related to anything else — must not be important, certainly not related to the rest of the system. But of course, A is the angle of the road, B is the gas pedal, C is the brake pedal, and D is the speed of the car.
In the past, GDP and resources use have always been tightly correlated. But this is just drawing a line through some data — it’s not based on any deep theory. And in fact, these correlations can change very quickly. Just as one example, here’s energy use versus GDP since 1949.
If you were sitting in 1970, you could look at this curve and claim, very confidently, that economic growth requires concomitant increases in energy use. And you’d be wrong. Because the trend is your friend til the bend at the end.
Karen Terry's house in Sante Fe, designed by architect David Wright, is perhaps one of the most compelling passive designs.
Stepping down its hillside site in four tiers, it nestles low into the ground. Thick adobe sidewalls create a strong sense of shelter and its banks of windows look resolutely to the sun. The image is very much of a house attuned to sun and earth.
Rather than providing the convenience of a constant indoor temperature regulated by a thermostat, a passively solar-heated house may go through an air temperature flux as great as 20ºF per day. People learn to live with this flux.
Living in a solar house is a whole new awareness, another dimension. I have the comfort of a house with the serenity of being outdoors—protected, yet tuned in.