Basically, you're looking for incandescent or halogen bulbs in your house. Incandescent are those round light bulbs that we had been using for a century or so to light our homes. Halogen bulbs are either small cone-shaped bulbs or little rod-like bulbs often found in desk or track lighting.

There are a number of slightly different units for comparing how much light a light bulb appears to put off, but the one that is often used to compare compact florescent (CFLs) and incandescent bulbs, for example, is lumens. Fortunately, most manufacturers of efficient bulbs put on their packages what the equivalent inefficient bulb is. For example, a 13 watt CFL is comparable to a 60 watt incandescent bulb. The best thing is to look at what wattage bulbs you currently use and then go to the store and find efficient bulbs that claim to have similar outputs. You can alternatively use this website to compare incandescent and CFL bulbs.

Go through your home and replace your inefficient bulbs with more efficient new ones. And don't forget to still be vigilant in turning them off when not in use. Keeping lower energy lights on for longer periods of time defeats the purpose of replacing them in the first place. As a final note, if you are wondering what to do with your CFLs when they die, check out our FAQ question addressing that issue.