City skylines have long been a symbol of innovation and prosperity. What you can’t see is that these same buildings are some of the largest energy consumers in the United States and are therefore responsible for significant amounts of the nation’s carbon pollution.

In August 2015, President Obama and the U.S. Environmental Protection Agency released the final Clean Power Plan, regulating carbon pollution from existing power plants for the first time. Since then, many cities have released Climate Action Plans, setting targets for carbon emissions. The success of these two initiatives are mutually dependent. EPA’s Clean Power Plan requires strong local action, and the Climate Action Plans of cities, in turn, need national policies to ensure affordable, reliable, low-carbon electricity. Georgia Tech has modeled low-cost pathways for compliance with the Clean Power Plan that accelerate the transition from coal plants to cleaner sources of energy. By also emphasizing energy efficiency, these pathways could temper the recent rapid growth of new natural gas combined cycle plants, and making the transition to a cleaner energy future more affordable.

A new analysis of the effects of such clean power pathways illustrates how commercial building owners and occupants can benefit from more efficient and more affordable air conditioning, lighting, electronics and other equipment, and from improved building shells as well as rooftop solar systems. For example, the analysis found that commercial building owners and occupants in the United States could realize annual electricity savings of $11.3 billion (6.7%) in 2030, compared to the business-as-usual case, if states were to adopt the Clean Power Plan pathway described above.

With a focus on energy efficiency, new integrated heat pump systems could replace the less efficient units that are commonly used on the rooftops of office buildings, schools, restaurants and big-box stores, tackling one of the most rapidly growing energy uses in the United States – air conditioning. Other policies include stricter building codes and strengthened equipment standards. These would produce a significant reduction in energy bills and carbon emissions.