This post originally appeared on Business Insider.
Chevrolet has found a unique use for the discarded cases of its Volt batteries—and it involves bats and ducks.
The Chevy Volt battery cover is made of thermoset, a type of plastic that’s difficult to recycle. And once the batteries are ready for use, the thermoset cases that shipped them become useless. Not anymore.
GM’s waste reduction expert, John Bradburn, gives new life to these cases by turning them into shelters for bats—and, with some tweaks, for wood ducks, owls, eastern bluebirds, and scaly-sided merganser.
Bradburn and his team have installed 700 nesting boxes for critters at GM’s 40 wildlife habitat sites in the past five years. A box can house up to 150 little brown bats, one of the most common species found in North America.
But research shows that bats are dying in great numbers due to the spread of a disease called white-nose syndrome. The loss of these nocturnal flying mammals is a dangerous development for the planet. Bats help maintain ecological balance by eating 2,000 to 5,000 insects in one night, and more than 500 species of flowers rely on them for pollination. A study in Science magazine even found that loss of bats could cost North American agriculture $3.7 billion.
A nesting box can at least make life a little easier for bats looking for a roosting spot. Here’s how Bradburn puts together a bat box using wood scraps, battery cases and nails:
In a recent tweak to the bat box, Bradburn went a step further by swapping the scrap wood used for laying pallets inside the box with old circuit trays pulled out from GM’s SUVs and truck engines.
“When I held the circuit tray up the length was about right and the width was perfect,” he said in a press release. “I figured with some epoxy adhesive applied and sand sprinkled on it to make for a grittier surface, bats would have no problem hanging on.”
See also: Scientists Just Created This Explosion-Powered Robot That Hops Around Like a Frog
