Is there any such thing as a "perfect" energy code? I recently posed this question to a colleague of mine - a gentleman with whom I have served alongside in multiple state code review committees over the years.

He poignantly offered, "While new energy codes may improve the energy efficiency of a building, it does not follow axiomatically that the building will use less energy."

Wait. What? I was hooked. Tell me more...

"The bigger philosophical problem for me has become that considering the Jevons Paradox and nature of the market, I don't think that any energy code will ever result in actually saving energy."

An interesting supposition. I decided to do some digging.

In the world of economics, the Jevons Paradox occurs when technological progress increases the efficiency with which a resource is used (reducing the amount necessary for any one use), but the rate of consumption of that resource rises because of increasing demand.

There are some interesting examples of the Jevons Paradox playing itself out in the built environment. There is also a compelling counterargument to the premise, which I fully subscribe to. I personally believe that it is imperative that we continue to pursue our high-performance endeavors because the alternative is certain failure to scale back energy consumption and curb carbon emissions.

Nevertheless, I decided to test this Jevons Paradox with regard to residential energy consumption. If the theory holds true, then for all of progress we have made since the energy crises of the 1970s (e.g., more efficient appliance, the Energy Star program, stringent energy codes), our increasing demand (e.g., larger houses, the proliferation of consumer electronics, the internet, and always-on "smart" appliances) will presumably result in a marginal net increase in residential energy use.

Pulling information from the Energy Information Administration - a division of the U.S. Department of Energy - our per capital residential energy consumption has gone up and down over the years. However, when I calculated the trendline, it was apparent that U.S. annual residential energy consumption per capita has risen about 1 percent every decade since the 1970s.

Somewhere, William Stanley Jevons has a smirk on his face.

Yet, as society strives to meet the resource demands of 9.7 billion people by 2050, many of them aspiring to live the same resource-intense lifestyle as U.S. residents, we may struggle to protect or restore nature and the benefits it provides us. Efficiency measures buy us time to make our whole economy more sustainable.