The “Rosenfeld”: Energy Efficiency’s New Metric

Move over Watt; the new metric of the moment is the “Rosenfeld.”

In the current era of increased investment in energy saving activities, the importance of communicating energy efficiency’s benefits in a clear and standard manner to decision-makers and constituents is underscored. Yet, many expressions of energy savings can be difficult to conceptualize or lack standard reference. In expressing potential electricity savings, “avoided power plants,” for instance, often replaces the more abstract “billions of kilowatt hours saved” to describe the potential of efficiency measures. However, there are many sizes and types of power plants, and the metric can mean different things to different people.

In “Defining a Standard Metric for Electricity Savings” published in the March 2010 issue of Environmental Research Letters, a group of scholars proposes a new metric, the “Rosenfeld,” which provides a simple and standard manner for referring to the electricity savings potential of efficiency activities. The metric is named in honor of Dr. Art Rosenfeld, who is considered by many to be energy efficiency’s foremost scholar and advocate.

In the article, one Rosenfeld is defined as "one avoided 500 MW coal plant operating at 70% capacity in that year" (assuming 7% T&D losses). The article details the circumstances where the Rosenfeld can be used appropriately - including in “back-of-the-envelope” calculations and high-level summaries for less technical audiences.

To find out how to use the “Rosenfeld” in your analysis and learn more about Dr. Art Rosenfeld’s contributions to the field of energy efficiency. Read “Defining a Standard Metric for Electricity Savings.”