With big buildings in St. Paul responsible for more than 40% of the city's greenhouse gas emissions, the city will now require owners to keep track of their energy and water use.

Called "benchmarking," the practice is gaining traction across the country as a way of pushing building owners to reduce their contribution to climate change by raising awareness of the resources they consume.

Minneapolis adopted its own benchmarking ordinance in 2013, and reported that energy use in private commercial buildings dropped 5.5% between 2015 and 2018. Edina and St. Louis Park have also passed benchmarking requirements. So have Chicago, Denver, St. Louis and other cities.

The state of Minnesota has adopted a goal to reduce greenhouse gas emissions by 80% by 2050.

St. Paul has laid out an even loftier climate goal: carbon neutrality by 2050. To get there, the city's buildings will have to become far more energy efficient. In St. Paul, 42% of greenhouse gas emissions are associated with heating, cooling and other energy use in commercial, multifamily and industrial buildings. Residential buildings account for another 20%.

The policy changes will require tracking in about 700 buildings in St. Paul, said Russ Stark, chief resilience officer for the city of St. Paul.

"The idea is that you manage what you measure," Stark said. "The act of taking the time to pay attention to energy and water use actually leads to exploration of ways to use less."

Cities across the country are recognizing that they have to reduce energy use in buildings to achieve their climate goals, said Sheri Brezinka, a regional director for the U.S. Green Building Council.

"Cities and communities that step up in a leadership role through benchmarking, whether it's mandatory or a volunteer program, [are] really key to helping make a difference on climate change," she said.

Brian Field, the property manager for a 13-story office building in downtown St. Paul called Infor Commons, said the building has reduced its energy use by at least 20% since it began voluntarily tracking the data more than 10 years ago.

"Building owners and property managers look to benchmarking as a step to find out where they are, or where they've been," Field said.

An analysis by the Environmental Protection Agency found that benchmarking can reduce energy use by an average of 2.4% each year.

"You can't make a difference with energy efficiency unless you're measuring it first," said Alison Lindburg, building energy policy manager with the Midwest Energy Efficiency Alliance.

People are fascinated by data, Lindburg said — think about how many people track their sleep, their steps or the temperature in their home.

"As more and more people understand what benchmarking actually is, you actually start to look at like, 'Wow, this is how much energy my building is using.' "

Cleo Krejci (cleo.krejci@startribune.com) is a University of Minnesota student on assignment for the Star Tribune.