Northgate Turns Food Waste into Energy

Northgate Markets has adopted St. Louis-based Emerson’s Grind2Energy system, which turns food waste into energy, to help address food waste across its stores.

The first California grocer to adopt the solution, Northgate found that its scraps from fresh-prepared operations added up quickly: Just one of the chain’s stores used six cases of avocados each day to prepare guacamole and other fresh items, equaling nearly 300 avocado pits and skins requiring disposal – but in somewhere other than a landfill, as required by California legislation that took effect in April. Grind2Energy’s process grinds food waste using a specially engineered, industrial-strength InSinkErator grinder. The waste is converted into a slurry, which is safely stored in sealed tanks before transportation to the Joint Water Pollution Control Plant, a Sanitation Districts of Los Angeles County facility and one of the largest wastewater treatment plants in the world.

From the plant, the material is put into an anaerobic digester, where bacteria and other microbes snack on the decomposing food in enclosed tanks. As the waste breaks down, the microbes release methane, which is then captured and used to generate energy.

Results already have been significant: Renewable energy, created from the chain’s food scraps, has been enough to power 52 homes and heat 78 homes for a month. The scraps have generated 20,394 pounds of nutrient-rich fertilizer. They’ve also made a big impact on greenhouse gas emissions, eliminating the equivalent of driving 234,385 miles.

In addition to the environmental benefit, Grind2Energy helps chains like Northgate Markets meet guidelines set forth by the Mandatory Commercial Organics Bill. The legislation requires high-volume commercial operations, such as supermarkets, to divert food waste from landfills.