While the federal government strives to reopen after a weeks-long shutdown, Washington, D.C. remains busy working on making its 30 million square feet of buildings more energy-efficient -- and it’s turning to startup FirstFuel for help.

That’s Wednesday’s news from the nation’s capital, where D.C.'s Department of General Services has announced that it’s working with the Lexington, Mass.-based data analytics startup to help it identify and carry out the most cost-effective efficiency projects it can find within its vast real estate holdings.

FirstFuel is one of a growing number of “virtual energy audit” providers that crunch massive amounts of data to yield insight into which buildings are wasting energy and how much they're wasting. That insight can be applied both to individual buildings, to bring them closer to their ideal states of energy use, and across portfolios, to see which properties represent the biggest return on investment for efficiency projects.

FirstFuel, which has raised $12.5 million in VC investment, leans heavily on fifteen-minute-interval meter data, collected from utilities from past years and on an ongoing basis, to apply what CEO Swapnil Shah calls its “inverse modeling” approach. It then combines that energy data with weather data, building location information and characteristics, and other site-specific information, and mashes it all into a set of strategies for owners and staff to roll out.

At the end of that process, the company measures and verifies the results over time, and adds that insight to its big-data stew. All in all, it promises a much more scalable and cost-effective solution than traditional methods of on-site energy audits, engineering assessments and project-by-project continuous commissioning do on their own.

Washington, D.C. has already joined cities like New York, Chicago and Seattle in putting energy benchmarking regulations in place for its public buildings, and earlier this year it launched its BuildSmart DC website to present energy and project data in a publicly available format.

“Our goal is to leverage data to make efficiency improvements in smart, big, and transparent ways, and FirstFuel’s advanced analytics are a key part of this effort,” Sam Brooks, associate director of DGS’s Energy & Sustainability division, said in Wednesday’s announcement.

(Shameless plug: I will be moderating a panel discussion entitled “Big Data for Energy Management Across Portfolios,” along with Shah, Brooks and Sandra Kwak, senior marketing and business development manager for energy data analytics startup AutoGrid, at Thursday’s VERGE SF conference in San Francisco.)

FirstFuel doesn’t go out and do the efficiency projects itself, leaving that to owners and contractors. But it has found that simple, nearly cost-free measures, like adjusting HVAC settings to avoid simultaneous heating and cooling or to turn the system on or off a few hours earlier or later, can account for just over half of the total efficiency opportunities across a wide swath of typical buildings.

In its initial 25-building run with D.C.’s DGS, FirstFuel has identified 19 million kilowatt-hours of energy reduction opportunity, or an average 24 percent energy use reduction per building. All told, more than 60 percent of available savings can be achieved through low- or no-cost operational changes, it found.

The next step will be to determine which buildings are wasting the most energy in ways that will require retrofits. Retroficiency, another Massachusetts-based virtual auditing startup, has found that the top 20 percent of buildings it sampled in a recent study had savings potential of more than 40 percent, while the bottom 20 percent only offered 3 percent savings.

Utilities are a target market as well, since they collectively hand out billions of dollars a year in efficiency rebates, incentives, cost-sharing grants, and other such funds and would like help spending that money more efficiently. Indeed, allowing the interests of utilities and the buildings that buy their power to align via big data is a big next step in the efficiency space -- something we’ll be discussing in more detail during tomorrow’s panel at VERGE SF.

Watch First Fuel CEO Swapnil Shah speak at Avant EE:

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