From Food Scraps to Fuel: Fueling a Fleet with CNG Made from Waste
There’s no denying that some renewable energy technologies are more visually appealing than others, especially the highly visible ones that look decidedly more ‘space-age’, such as solar power and wind power, but it’s going to take a variety of approaches, including not-so-sexy technologies such as converting waste to energy, to create a true clean energy future.
One of the more common waste products in the developed world these days is food waste (which is a sad truth in a world where so many have so little to eat every day), and while food scraps can be converted into soil-building compost, or used to generate methane, it can also be collected and converted into compressed natural gas (CNG), which can then be used to fuel vehicles.
Jeff McIntire-Strasburg highlights how one business is doing it:
Turning Food Waste Into Compressed Natural Gas (CNG)
Anaerobic digestion is a process that uses microorganisms to break down biodegradable material in the absence of oxygen. South San Francisco Scavenger Company and its partner, Blue Line Transfer, are the first in America to use dry anaerobic digestion technology to convert food and yard waste into clean-burning compressed natural gas (CNG). Other digesters produce methane, which is then burned to generate electricity.
The company will use the fuel produced by its digester in its fleet of CNG-powered trucks. “We’re excited about the new digester because it allows us to turn compostable food scraps into fuel for the very trucks that collect those materials. It’s a truly closed loop system,” says company president Doug Button. “Plus, the process keeps organic waste out of the landfill and cuts greenhouse gas emissions—benefiting the communities we serve, the environment and our company.”
Made by Zero Waste Energy, LLC, the Blue Line Transfer anaerobic digester produces up to 500 diesel gallon equivalents (DGE) each day of carbon negative, renewable CNG. In addition, the process provides digestate, a nutrient-rich substance that will become certified organic compost. Compared to traditional composting, the dry anaerobic digestion process creates fewer greenhouse gas emissions and other air pollutants.
SSFSC plans to process 11,200 tons of food waste and food soiled paper every year from its customers in South San Francisco, Brisbane, Millbrae, Colma and the San Francisco International Airport. The new technology will serve an expanded push to sign up businesses for food scrap and food soiled paper collection.
Reprinted with permission.