How Do We Get Energy From Trash?


One man's trash is enough to power another man's home… and a bunch of it can power 20,000 homes… So what are we waiting for?? You guys, a company called GreenSky is taking in sorted municipal and commercial waste and outputting JET FUEL. Yep. Trash to airplane fuel. Boeing flew a 787 using biofuel last year to prove it could be done, but GreenSky wants to make enough fuel from trash to supply ALL the needs for London City Airport. British Airways has pledged to purchase ALL 50,000 metric tons of fuel from GreenSky! They're going to fly all over using your TRASH for fuel and also charge you to put a bag into the bin… not the trash bin, Brits, the OVERHEAD bin. Look, trash is everywhere. We throw away 4.3 pounds (2kg) of waste every day and 55% of all the trash generated in the United States goes into landfills. But, according to Scientific American, if we converted the 460 million tons of trash produced in North America properly, we could make 12.4 billion gallons (47B liters) of ethanol.

That's a lotta hooch — roughly the same amount as produced from all ethanol-bound corn. And the process is REALLY easy; all you need is to unleash some sulfuric acid to break down the cellulose, and some select enzymes and microbes to ferment the resulting slurry into fuel. Done, you're flying. Biofuel from trash is great, but we need to separate the trash BEFORE we can do that. So while we use that in the future, we can ALSO burn grandpa's trash too! In 1986 there were over 7,600 small dumps, today there are around 1900 mega-dumps which should have enough capacity for centuries of garbage. In 2008, power from landfills exceeded solar power production in New York and New Jersey, and it's expanded significantly in the last seven years. Of the 1900 landfills over 640 have added the technology to harness the power of landfill gases (LFGs) and converting them to energy. LFG is produced by anaerobic bacteria (bacteria that doesn't need oxygen) buried deep within landfills.

The anaerobic bacteria munch on our trash and poop out methane which would NORMALLY be real bad. Methane is 20 times more potent a greenhouse gas than CO2, and according to the EPA, municipal solid waste is the third-largest source of human-related methane emissions in the US. But, if we capture it before it floats up and makes climate change worse, we can use it for good AND chillax with some oil burning too. Methane is an odorless, colorless hydrocarbon (CH4), and because the bacteria are trapped underground, companies can find pockets and suck it out with high-vacuum pipes. Once collected, the methane is cooled, cleaned, and mixed with mercaptan to give it a detectable odor before they send it out to natural gas plants to be burned for fuel. Yep, natural gas can come from rock, or oil deposits but that's a "dirty" natural gas, a mix of 99 percent methane with some propane, ethane and sulfur and helium mixed in. The biomass methane is pretty much just CH4.

Bacteria are good like that. The EPA's Landfill Methane Outreach Program is hoping to encourage companies to set up on top of landfills and suck in as much methane as possible, because otherwise we're just letting dollars float away. As of 2013, LFG captured energy was powering 1.8 million homes. So just to recap, we throw away a lot of stuff and just let it sit there, but thanks to these technologies getting trashy could clean up the world..