New Unit of Measurement Honors Energy Efficiency Champion

There's a new unit of measurement in town.

The Rosenfeld – named after the "father of energy efficiency" Dr. Art Rosenfeld – will help standardize references to “energy saved”, rather than such variable calculations as “avoided powerplants” or “cars off the road.”

It is hoped that, with frequent use, the Rosenfeld will join the Watt and Joule as widely used measurements that not only help evaluate and measure the science to which they apply, but also honor the achievements of their namesakes.

The announcement took place at a special symposium honoring Art Rosenfeld at the University of California Davis. Here, Dr. Rosenfeld's colleagues Dr. Jonathan G. Koomey and others from Lawrence Berkeley National Laboratory in California presented their article, "Defining a Standard Metric for Electricity Savings", which describes the Rosenfeld as being equivalent to the following:

...the average coal plant capacity of 500 MW, a capacity factor of 70% (the average capacity factor of existing US coal plants from 1996 to 2007), and systemwide T&D losses of 7% (rounded up from 6.7% for ease of recall). This combination of parameters would yield annual electricity delivered at the meter of about 3 BkWh/year. Using the carbon burden for US utility coal and the efficiency of average existing coal steam plants, the emissions saved are almost exactly 3 million metric tons of CO2 (Mt CO2) per year.

Complicated as the formula may sound, it is a simplification of more complex energy efficiency measurements – and "all simplifications are imperfect," as the article notes. Dr. Koomey and his colleagues go on to say that "the Rosenfeld can best be used in rough back-of-the-envelope calculations and high-level summaries of analysis results for less technical audiences."

Accuracy notwithstanding, the Rosenfeld offers the energy efficiency lexicon a new tool with which to talk about climate change. By standardizing the link between energy saved and infrastructure, the term will help promote what Dr. Koomey and his colleagues call "a significant shift from the status quo ... an internalization of societal costs that heretofore have not been included in the operational and investment decisions of electric utilities."

In other words, the Rosenfeld is a simpler way of talking about energy efficiency's benefits to the economy, the environment and energy security.