It may be the best-kept secret in home real estate: For a couple of hundred dollars, a prospective buyer can add a formal energy audit to the standard inspection. That audit might save the buyer thousands of dollars in future operating costs by pinpointing features of the house that need correction to improve efficiency. It might also be a tip-off to a sobering reality: This house is an energy guzzler. And that might prompt the buyer to say: Either the asking price comes down, the seller fixes the problems, or I walk!

A solar micro-inverter converts direct current (DC) electricity from a single solar panel to alternating current (AC). The electric power from several micro-inverters is combined and fed into an existing electrical grid. Micro-inverters contrast with conventional string or central inverter devices, which are connected to multiple solar panels.

A rising trend of super-efficient, solar-powered new homes allows homeowners to combat rising energy costs by giving back to the power grid. Some owners are even realizing a small profit from their home's power-generating capacity. Intelligent house layout and design,