INTRODUCTION You would think that energy efficiency is relatively simple: perform an energy audit, install the retrofits and then reap the energy savings. Unfortunately, it doesn”t always work that way. We performed an energy assessment of several stores of a major retail chain in the San Francisco Bay Area and identified a handful of low-cost retro-commissioning measures that had very promising potential. We quantified the expected savings and costs and returned after the project was installed. We then measured the savings using various methods and found either minimal or negative savings. The problem we discovered was that on nearly every…