Smart buildings are key to a greener future. These companies are leading the charge

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Lights are on in all the conference rooms. Each room is cooled to the same pre-set temperature. But there's only one person on the entire floor.

This is an all-too common phenomenon—and problem—in commercial spaces big and small across the U.S. (and never more so than in the time of Covid, with few people working in big-city buildings). As the country pushes toward a cleaner future, making buildings more efficient is key. Energy efficiency is a "vital part of the sustainability story" and a "very needle-moving dimension of decarbonization," Raymond James noted in a recent report.

Recognizing the environmental impact of buildings, President-elect Joe Biden has made sustainable buildings a priority within his climate plan. Building newer and cleaner buildings plays a part, but that's not enough: older buildings also need to be upgraded. As states and cities beef up their building codes, there's a real opportunity for a number of companies working on digitizing buildings, three of which stand out: Honeywell, Johnson Controls and Schneider Electric. All three offer digital platforms for customers that monitor and track every inch of a building's metrics. The systems harness the power of big data and machine-learning to deliver the best overall experience, tailored to the needs of each specific customer, whether it be an office building, a hospital, a shopping mall, or an airport.