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Danish City to Power Water Treatment Plant Using Sewage

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Every city produces sewage, but now, Aarhus, Denmark is hoping to prove that their waste doesn't have to be, well, wasted. As New Scientist reports, the Danish metropolis will become the first city to power its water system using energy harnessed from sewage and wastewater.

After undergoing a $3.2 million renovation, Aarhus’s Marselisborg Wastewater Treatment Plant is now capable of creating heat and electricity out of biogas. The waste is served up as a meal to bacteria kept in 100-degree "digesters," or large tanks. Byproduct gases like methane are then burned, generating more than 150 percent of the electricity required to power the plant. Any surplus electricity is either used to supply fresh water to the city of 200,000, or is sold back to the grid.

The concept of using human waste as an energy resource isn’t a new one: Last year a study from the United Nations University’s Institute for Water, Environment, and Health reported that biogas produced by all the world’s human poop could provide energy to up to 138 million homes. Aarhus is the first city to integrate this innovative idea into their water system, and now cities like Chicago, San Francisco, and Copenhagen are interested in following suit.

For Aarhus’s success to be recreated elsewhere, water plants need to be big enough to produce large amounts of biogas and the wastewater they use has to be the right makeup (too much water dilutes the energy content). Cities also need to have the funding to make the necessary infrastructure upgrades. Aarhus Water’s investment in their plant was pricey, but savings in maintenance and electricity sold to the grid are expected to make it up in five years.

[h/t New Scientist]

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Are You Eco-Conscious? You Could Win a Trip to the Dominican Republic
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Do you love lounging on the beach but also want to take action to save the planet? You'll be able to do both if you're chosen to serve as a "sustainability advisor" for a luxury resort in the Dominican Republic, Lonely Planet reports.

The worldwide contest is sponsored by Eden Roc at Cap Cana in Punta Cana. The winner and one friend will receive a five-night stay at the Relais & Châteaux hotel, where they'll partake in specially curated activities like a food-sourcing trip with the hotel's chef. (One caveat, though: Airfare isn't included.)

You don't need a degree in conservation to enter, but you will need an Instagram account. Give the resort's Instagram page (@edenroccapcana) a follow and post a photo of you carrying out an eco-friendly activity on your own page. Be sure to tag the resort and use the official hashtag, #EcoEdenRoc.

The only requirement is that the winner meet with hotel staff at the end of his or her trip to suggest some steps that the hotel can take to reduce its environmental impact. The hotel has already banned plastic straws and reduced its usage of plastic bottles, and the sole mode of transport used on site is the electric golf cart.

Beyond the resort, though, the Dominican Republic struggles with deforestation and soil erosion, and the nation scored poorly on the 2018 Environmental Performance Index for the agricultural category.

Entries to the contest will be accepted until August 31, and you can read the full terms and conditions here.

[h/t Lonely Planet]

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Mark Ralston, AFP/Getty Images
How a Hairdresser Found a Way to Fight Oil Spills With Hair Clippings
Mark Ralston, AFP/Getty Images
Mark Ralston, AFP/Getty Images

The Exxon Valdez oil tanker made global news in 1989 when it dumped millions of gallons of crude oil into the waters off Alaska's coast. As experts were figuring out the best ways to handle the ecological disaster, a hairdresser from Alabama named Phil McCroy was tinkering with ideas of his own. His solution, a stocking stuffed with hair clippings, was an early version of a clean-up method that's used at real oil spill sites today, according to Vox.

Hair booms are sock-like tubes stuffed with recycled hair, fur, and wool clippings. Hair naturally soaks up oil; most of the time it's sebum, an oil secreted from our sebaceous glands, but it will attract crude oil as well. When hair booms are dragged through waters slicked with oil, they sop up all of that pollution in a way that's gentle on the environment.

The same properties that make hair a great clean-up tool at spills are also what make animals vulnerable. Marine life that depends on clean fur to stay warm can die if their coats are stained with oil that's hard to wash off. Footage of an otter covered in oil was actually what inspired Phil McCroy to come up with his hair-based invention.

Check out the full story from Vox in the video below.

[h/t Vox]

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