Editor's Note: To learn more about energy-efficient buildings, check out VERGE@Greenbuild, November 12-13, in San Francisco.

A growing number of companies are realizing the social, environmental and cost benefits of retrofitting their buildings.

Earlier this month, accounting giant Ernst & Young (ERSNP) announced the completion of an energy-efficient lighting system at its New York headquarters. The project – one of the city’s largest light retrofits – will cut the building’s annual energy use by nearly 2.9 million kilowatt-hours and reduce its CO2 emissions by around 2 million pounds.

The market for energy efficient retrofits in commercial buildings -- particularly in energy management software -- is set to grow exponentially. It will nearly double by 2020, according to a recent study by Pike Research. Published last month, the report predicts that the global market for retrofits will increase from more than $80 billion in 2011 to nearly $152 billion by 2020.

The emerging market is shifting away from one-time retrofits to making buildings more efficient on an ongoing basis through software, said Eric Bloom, a senior analyst at Pike. Traditional building companies like Johnson Controls as well as software companies like SkyFoundry are developing software applications that can help building owners monitor energy in real-time and regularly respond to inefficiencies and equipment malfunctions, Bloom said.

“The reality in the building industry is that most of the technology needed to make buildings more efficient has already been developed,” he said. “This will spur a shift from one-time, labor-intensive retrofits to an ongoing stream of small improvement measures that will add up to a more efficient building over time.”

Photo of control panel provided by Viktor Gladkov via Shutterstock

Next page: The most popular – and greatest untapped potential – place for energy-efficient retrofits