Wall and attic insulation are one of the most cost effective ways to reduce home energy usage. There is also significant innovation in this category with environmentally friendly materials. For the materials themselves — mineral wool, recycled denim, sheep's wool and cellulose — see Insulation under Green Materials.

There are a lot of options for energy efficient windows, and it is one of the most innovative categories for the home.

Smart electric receptacles, switches, and lighting provide convenience and control, and also help reduce energy usage across the home.

Radiant heating is the most energy efficient way to heat the home, and is a great complement to Solar power. Radiant heating also increases comfort, due to even distribution of heat through the environment.

Tankless water heaters have come down in price over the past few years. They reduce water usage, save energy, and electric tankless water heaters can be run from Solar power.

There are a huge number of options for coordination of smart home components, with Amazon and Google leading the pack.

Smart appliances are evolving in functionality and can help significantly reduce energy and water usage.

Zoned ductless electric heating and cooling is very efficient and works seamlessly with smart thermostats.

Electric car charging from power generated by the PV system lowers operating costs and can virtually eliminate greenhouse gasses emitted.

Solar landscape and patio lighting is both functional and beautiful, with design options for all homes.

Battery storage is a key component of a home PV system, as it allows storage of excess energy created for later use. There are significant ongoing improvements in both the cost and storage capacity of these systems.