Our buildings have a big environmental footprint, from their construction to their daily operation. In the U.S., residential and commercial buildings account for about 40% of the country’s energy use. A lot of that energy, it turns out, isn’t even necessary: It’s just being wasted. By just changing the way buildings control their lighting, heating, cooling, and appliances through smart energy analytics, a four-year initiative by Berkeley Lab saved $95 million per year in energy costs across 6,500 buildings.
When Sprint implemented energy management information systems (EMIS)—which includes sensors, meters, and data analytics software to allow building operators to see exactly when and where energy is being wasted—at its headquarters in Kansas through the Berkeley Lab effort, the company saved $400,000 in energy bills and more than 4.7 million kilowatt hours of energy a year. When Stanford University installed EMIS software at 315 housing and food-service sites, its electric bills went down 5% and its gas bills by 10%, saving the university’s residential and dining services $451,000.
“Usually when we’ve talked about building energy efficiency or performance, people’s minds go to design of the buildings, and things like LEED new construction certification,” says Jessica Granderson, deputy of research programs for the Building Technology and Urban Systems Division at Berkeley Lab, who led the four-year building efficiency campaign. But we don’t need large capital investments or complete redesigns to get big energy benefits. “There’s a huge untapped opportunity with these [EMIS] technologies that are focused on how we actually day-to-day operate and control our buildings. That’s another dimension of efficiency.”
If commercial buildings nationwide adopted these EMIS technologies and best practices, Berkeley Lab says the energy cost savings could total $4 billion. That means drastically fewer emissions and fossil fuel use. “Any time we talk about building energy use, there are environmental implications,” Granderson says. “The majority of electricity generated is used to power buildings, and buildings are accountable for a significant portion of greenhouse gas emissions. Those emissions are tied to the fuels we use for space heating and water heating and the electricity being consumed.”
Along with the monetary savings, the Berkeley Lab campaign drove an annual energy savings of 4 trillion BTU—a unit of measurement for heat energy. One trillion BTU is equal to 500 100-ton railroad cars full of coal.
Why are our buildings so inefficient in the first place? Many systems just aren’t optimized. An HVAC system might be making a building feel comfortable, but it’s heating and cooling simultaneously. Maybe an electric or air conditioning system was put into a different mode for maintenance, and never put back. Maybe a building isn’t actually programmed to shut down and set back overnight or on holidays.
The EMIS technology does have an upfront cost; on average, installation and software costs ranged from two to eight cents per square foot. Berkeley Lab says the investments pay for themselves in two years. The average participant in the campaign, whether a school, government, or other institution, saved $3 million in annual energy costs across their building portfolio.
Granderson sees this as this EMIS technology as a critical step toward “smart” buildings, and operating our buildings in tandem with a smart, clean energy grid. That also would lead to other benefits besides energy savings. “Buildings that are well-tuned, well-controlled, and operating as intended really sets the stage for the future, and that’s realizing the promise of healthy buildings, buildings that offer a high degree of service, productivity, and comfort to occupants,” she says. “That’s why we have our buildings in the first place. They’re not built just to consume energy.”