Kahle Wightman
For many, taking out the trash is part of a nightly ritual. Despite your best efforts in trying not to be wasteful, recycling what you can, and making do with all your food scraps, you still have an assortment of solid waste bouncing around in your trash bag as you toss it into the black bin outside. The containments of the trash bag vary day to day, but the trash bag itself is a constant variable in this routine. Not only do trash bags actas a hygienic barrier between you and your waste, but their main purpose is also to safely carry this waste to its primary destination: a landfill.
Landfill Gas to Energy
Although many are put off by the word “landfill,” the breakthroughs in the waste management industry in the last two decades should not be ignored. Today’s modern landfills are engineered to keep waste from entering the outside environment, as well as designed to capture the methane that arises from decomposing waste. A growing majority of these landfills use this captured methane to produce renewable natural gas, with countless new landfill gas-to-energy projects being announced on a weekly basis.
Landfill gas-to-energy technology is taking the U.S. by storm. Take California for example, the state with the highest number of LFG facilities. According to the U.S Environmental Protection Agency, California has 56 landfill gas-to-energy projects and counting. Across the country in Michigan, they have over 40. Down South,the state of Georgia has 18. The list goes on. Chances are, if your municipal solid waste is being collected by a waste management company every week, then it is being sent to a modern landfill designed for methane-capture and energy production.
This alternative energy source is powering homes and business all across the nation. From companies like Coca-Cola, to BMW, to entire neighborhoods and towns. The Monarch Hill landfill in Pompano Beach, Florida generates nearly 11 megawatts of electricity, which is enough to power 9,000 homes per day. Over in Las Vegas, the Apex Landfill (the largest landfill in the country) captures enough natural gas to power their fleet of garbage trucks, in addition to 11,000 local homes.
Plastic Bag Waste
Unfortunately, no matter how these landfills are engineered, plastics cannot contribute to this energy capture process. They take hundreds of years to break down in these anaerobic environments, meaning the billions of trash bags we send to landfills each year are literally being wasted.
Let’s say these trash bags were able to decompose within the time frame that a landfill manages the gases being omitted, how valuable would they be? If every single trash bag was designed for microbial breakdown in anaerobic environments according to ASTM D5526 testing standards, it would mean that in landfill conditions, a complete biological breakdown of the plastic would take place and leave only water, humus, and gases (CO2 and CH4) behind. Conservatively assuming that roughly 60% of the carbon in the material is converted to biogas within the time frame of gas collection, a 45 gallon, 1.5 miltrash bag would produce roughly 0.22 kWh of energy (based on the energy value of methane).
Now, 0.22 kWh doesn’t sound like much in the grand scheme of things, until you think about how many trash bags are being sent to a landfill every single day on both the commercial and residential side. To put it in perspective, one large hospital alone can use up to 1 million trash bags per year. How many major hospitalsare within a 100 mile radius of you at this very moment?
According to the U.S Energy Administration, the average American family uses 10,791 kWh annually to powertheir home. Using our 45 gallon, 1.5 mil trash bag example from earlier, that would be the equivalent of 49,000 bags in a landfill gas-to-energy facility. Although the number is tough to pinpoint, some accounts claim that Americans go through over 1.25 billiontrash bags per year. After punching in a series of zeros on your calculator, it’s easy to see how the value of one trash bag adds up.
Back Into Energy
Both producers and consumers of trash bags need to acknowledge where their waste is actually heading and embrace the innovations in landfill gas-to-energy technology. Our responsibility as stewards of both the environment and common sense, is to demand that trash bags should be designed to break down after disposal in the specific environment they end up in: landfills. This breathes new life into the concept of “circularity”, where there currently isn’t any circular-solution at all. It takes energy to make these trash bags, now let’s turn them back into energy.