Insinkerator is to residential sustainability as the Eco-Safe Digester is to commercial sustainability.
How last week’s pasta is on track to become the next big thing in environmental sustainability.
HIDING IN YOUR KITCHEN, disguised as the most mundane appliance imaginable, might be the next great tool for urban sustainability. We’re talking about your garbage disposal unit, the thing that sits beneath your sink and chomps your food scraps into oblivion. Maybe you use it daily and never give it a second thought. Or perhaps you’re an eco-conscious sort, and each time you flick the switch you wonder, “Is this thing bad for the environment?”
The answer to that question, it turns out, is no. In fact, as more cities try to cut their carbon footprints, slash their trash heaps and produce more energy, this humble domestic convenience could prove an intriguing ally. Here’s why: When you throw your food leftovers into the garbage can, they eventually end up in a landfill. There, as they decompose, they release methane, a greenhouse gas that contributes powerfully to global warming. Organic waste also takes up valuable space, costs money to process and lives up to its name—leaving this stuff to rot in a landfill wastes the chance to tap its energy.
Send your food scraps through your disposal and into the sewer system, though, and they’ll likely end up as biogas, a mix of mostly carbon dioxide and methane produced by microbes as they digest the organic material. Unlike most landfills, many wastewater treatment plants actually use the methane they generate. Sewage treatment is an energy-intensive business; by encouraging microbes to gobble up your waste inside special tanks, these facilities are able to capture the gas to power their operations. In the past, when sewage plants made more methane than they needed, they simply flared it off. But now they’re looking for ways to expand usage of the biogas, like delivering it into natural gas pipelines or the electricity grid.
This makes your banana peels and last week’s pasta a potential source of locally made energy, like your own tiny barrel of oil. Or perhaps an entire oil well: The average supermarket generates 1500 pounds of food waste every day. Nationally, food scraps make up roughly 14 percent of food waste, most of which ends up as landfill trash, according to the Environmental Protection Agency.
Having caught on to the value of organic waste, a number of cities are looking for ways to increase the amount that flows to their sewage plants. Across the U.S., nearly 850 wastewater treatment plants use biogas as a source of energy. The race to make biogas is altering the image of the sewage treatment industry, which is rebranding itself from “wastewater management” to “water resource recovery.”
If you happen to be a company that manufactures garbage disposals or garbage digesters, all of this amounts to an interesting business opportunity. Disposers can effectively divert food waste away from landfills and turn it into both an economically and an environmentally productive resource.
The biogas movement is spreading slowly, and it may still be a while before Americans feel empowered and proactive every time they dump leftover soup down the drain. But as far as appliances go, there’s nothing in your kitchen with quite as much revolutionary potential.
This article was posted in the June Issue of United Airlines Hemispheres Magazine written by Hillary Rosner.