From solar panels to airtight windows to geothermal systems and more, these experts are building and remodeling their homes ...

All that energy creates ... in less efficient spots. Those panels would generate 7,811 kilowatt-hours of electricity in the first year – covering roughly 70 percent of the home’s overall ...

There are roof shapes and ratios that maximize heat retainment and energy efficiency and, interestingly, ancient Italian architects and builders seemed to know it, too.