Energy-efficient building upgrades are one of the most effective and cost-efficient conservation methods to take, according to a two-year study by New York-based McKinsey & Co. The study predicts that energy upgrades alone could reduce greenhouse gas emissions by up to 870 megatons by 2030, the equivalent of removing 170 million vehicles from the roads.

The corporate-funded report, “U.S. Greenhouse Gas Abatement Mapping Initiative,” includes interviews with government officials and private companies. Decreasing vehicle emissions is the second most effective conservation method, the McKinsey report says, followed by reductions in energy-intensive industries, expanding and enhancing “carbon sinks,” such as forests, and reducing emissions from electricity generation.

The report concludes that, while reducing emissions has short-term costs, it should stimulate economic development and growth. The entire report is available at www.mckinsey.com/greenhousegas.