Solar panels and smart meters aren’t the only ways that homeowners can color their energy use “green.” According to recent data, upgrading homes with some basic measures can dramatically reduce energy use as well as carbon emissions.

In December, the American Council for an Energy-Efficient Economy (ACEEE), Washington, D.C., released a report, “Pathways to Residential Deep Energy Reductions and Decarbonization,” which finds that upgrading homes with measure such as thick insulation, thorough air sealing and efficient heat pumps can more than halve residential energy use and carbon emissions.

The report highlights so-called “deep retrofits,” which can cut a home’s energy use by anywhere from 58% to 79%. At the same time, these upgrades will also reduce the home’s emissions by 32% to 56%. Retrofits include a range of upgrades. Some are simple and inexpensive, while others are more costly. On the lighter side, homeowners can switch to LED light bulbs or buy insulated shades. A bigger investment might involve replacing a furnace, windows or the roof. ACEEE notes that for longer-term carbon reductions, residential users can shift to electric heating and cooling, especially through heat pumps.

In compiling the report, ACEEE analyzed retrofit packages based on the most common pre-2000 home type in each major U.S. climate zone. Not surprisingly, the results showed that a home’s age and location influenced which retrofits would be most effective and how much a homeowner would need to spend.

ACEEE also found that the most effective upgrades are more expensive than the average homeowner can afford. For this reason, it says the government needs to step up. According to Jennifer Amann, senior fellow for the buildings program and the report’s lead author, “The government needs to help scale these retrofits by subsidizing them, training contractors and encouraging electrification.”