Conservation Guardians of Northwest Illinois

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Dark Sky, Did You Know?

1	A 175-watt mercury vapor dusk-to-dawn light wastes nearly half of its $50-60 yearly energy costs on light that goes up and never reaches the ground. A more cost-efficient option is to purchase a 70-watt high pressure sodium lamp with cap that directs the light downward (for about $130) that costs about $22 per year in energy, but wastes none of the light. The purchase cost can be re-couped in 3-4 years.
2	If you replace a 60-watt incandescent with a 15-watt compact fluorescent bulb and use it 6 hours a day, you would get the same amount of light but could save more than $40 in energy cost over the 4-year life of the bulb. You'll also save the cost of purchasing at least 8 incandescent bulbs during the lifetime of the compact fluorescent bulb.
3	In new residential construction a recessed canister underneath a porch roof or overhang is an excellent means of hiding light fixtures. They "light the object, not the source." If a house has wood siding and wall-mounted lights beside the front or back doors, it's possible to utilize an excellent light shield. Just have wooden boxes (painted the same color as the siding) built over the lights. This maintains a rustic look, too.