Swapping your five most frequently used light fixtures or their bulbs for Energy Star-qualified compact fluorescent lamps can save money -- more than $165 a year, according to Energystar.gov, a U.S. Department of Energy and the Environmental Protection Agency website.

Fluorescent lamps use an estimated 75 percent less energy, generate 75 percent less heat and last up to 10 times longer than incandescent light bulbs. And while a $2 four-pack of incandescent bulbs may seem like a better deal compared to $2 to $15 a piece for these lamps (for 40, 60 or 100 watt lamps, respectively), the more efficient fluorescent lamps use about $130 less in energy costs per bulb over their lifetimes, according to Energystar.gov.

Let's say you're lighting up 10 rooms with three bulbs each. Switching to the pricier compact fluorescent lamps actually saves you nearly $3,900 in the long-run, according to Energystar.gov.