Making buildings energy-efficient is harder than we think, for reasons that are unclear

A reader (hi, Pete!) pointed me to a story from LawandEnvironment.com about a study which found that making buildings more energy efficient is harder than we think, even when factoring in the fact that it's harder than we think:

Over the past 20 to 30 years, every important building component has improved in energy performance. From air conditioners to lighting to windows, construction crews today have an array of green technologies at their disposal.

Once they're put together, though, the finished building performs no better than its predecessors of two or three decades ago. The parts have gotten better, but not the whole.

The whole story is here. It references a longer piece that's behind a paywall, which in turn references a study by Greater Philadelphia Innovation Cluster for Energy-Efficient Building, a DOE "energy hub" connected with Penn State.