Boston-based WegoWise, a building-performance analytics startup, says it was able to identify $137 million in lifetime energy savings in 2011 for buildings that are part of Mass Save's Low-Income Multifamily Program, which invests in energy-efficiency upgrades in low-income housing facilities across Massachusetts.

The multiyear program is being implemented by the Low-Income Energy Affordability Network (LEAN) and the Mass Save sponsors—Massachusetts utility companies—that have used the WegoWise platform to track and benchmark energy and water use at more than 45,000 low-income multifamily units in the state. Barun Singh, WegoWise founder and chief technology officer, says the platform enabled LEAN to look across entire portfolios of low-income housing to identify the "outlier" buildings that were underperforming. The building owners could then perform audits and target retrofits for the least efficient buildings.

"WegoWise has been instrumental in how we operate," says John Wells, LEAN co-chairman. "Now that we can capture total energy [and] water usage for multifamily properties, we can be far more strategic about our energy-efficiency retrofits and generate cost reductions."

Cities and municipalities increasingly are using benchmarking to measure building performance to identify where to target retrofits. The states of Washington and California and the cities of Seattle, San Francisco, Austin, Washington, D.C., Philadelphia and New York City have passed ordinances or laws requiring some form of building energy benchmarking.

In November, the San Francisco Public Utilities Commission (SFPUC) released a report that detailed energy usage information for more than 300 municipal buildings. The report found that overall energy use in 2011 declined 3.8% from 2010 and 1.1% from 2009, which translates to some $1 million less in 2011 energy costs than for 2010.

The SFPUC report was released before a local benchmarking ordinance went into effect in 2011. Charles Sheehan, SFPUC spokesman, says the city has been benchmarking for years. Entering the data into one report allowed the city to compare how buildings performed in relation to each other as well as to similar facilities throughout the U.S., he says.