 Our energy efficient house is located in Los Angeles, California.  The 3 energy reducing features in our home are solar panels, Energy Star light bulbs, and Energy reducing windows.

House Description  Our house contains three energy reducing features. First we have energy reducing solar panels. These are a connected assembly of photovoltaic cells. The solar panel can be used as a component of a larger photovoltaic system to generate and supply electricity in commercial and residential applications. The efficiency of a panel determines the area of a panel given the same rated output.

House Description(continued)  A single solar panel can produce only a limited amount of power so most installations contain multiple panes. A photovoltaic typically includes an array of solar panels, an inverter, and sometimes a battery and a solar tracker and interconnection wiring. Next, is the energy star light bulbs which can save 75% of energy or more; you will see a $14 dollar fixture on your energy bill. Our third energy saving feature is energy efficient windows. Energy-efficient windows eventually pay for themselves through lower heating and cooling costs, and sometimes they pay for lighting costs.

Sources  =lighting.pr_lighting_landing   ceEnergy.htm  energy-efficient-windows