As one writer in Seattle King5’s Home & Garden section wrote: “It isn’t enough that the world should go green. It should go dark green. As in, turn off all the unnecessary lights, please.

Here are some myth busters about turning lights on and off from Green Energy Efficient Homes

Turn off lights when you’re not using them

The International Dark-Sky Association has been around for several decades, Many people see the issue of turning off the lights at night as something that’s merely aesthetic, a topic that has little to do with the health of our planet and our night skies.

But the over-illumination of the night sky actually has two very important environmental implications. For one, most outdoor lighting shines out and up, causing unnecessary amounts of light in the natural environment. This sky glow can actually harm the migration, mating, and feeding habits of all kinds of wildlife—from frogs to turtles to bats to moths. These creatures, mistaking our lights for the moon, or scared away by the lack of privacy, either have to find other ways to get where they’re going, or they die trying. This causes enormous losses that we’re only now beginning to understand.

But another important issue at stake is that of energy inefficiency. By sending light where it’s not needed—up and out, rather than down—we’re actually spending money to light up areas that will never be used by humans. This results in tons of energy down the drain, and loads of CO2 up into the atmosphere.

Choosing dark sky compliant lighting, then, makes us good environmentalists—the greener for having taking notice of the eco-impacts of our outdoor lighting choices. I, for one, am happy to go a litter darker, if it means I can be a little greener.