Small, window-mounted heat pumps could bring massive energy savings — and quieter, individualized temperature control — to tenants and others living in multi-unit apartment and condo buildings with centralized heating, the AP reports. New advances have both increased the efficiency, and decreased the size of heat pumps such that some are now about the size of a window unit air conditioner, if not less obtrusive.

“Look, I even have it for decoration,” Regina Fred told the AP, describing the new units in her Queens apartment as “very beautiful.” Fred’s heat pumps were installed as part of a NYC Housing Authority pilot project to cut energy costs and climate pollution. Building operations are responsible for more than one-quarter of global climate pollution and centralized steam boilers burning oil or methane gas not only lose 30% to 80% of their heat to leaky ductwork, but the one-setting-heats-all nature of the systems can leave some tenants shivering while others open windows to cool their overheated apartments.

Heat pumps are so efficient they reduce climate pollution even if powered by a fossil fuel-heavy grid, and small, easy to install models like Fred’s represent an especially effective way to lower building emissions because they obviate the need for new construction. (Window units: AP; Grid: Canary Media)