If we can turn sewage into energy, why not food—at least this is US-based Kroger’s plan for contributing to clean energy production initiatives.
US based Kroger unveiled a clean energy production system that will convert food that can't be sold or donated into clean energy to help power its Ralphs and Food 4 Less food division.
The system utilizes anaerobic digestion, a naturally occurring process, to transform unsold organics and onsite food-processing effluent into renewable biogas which is then turned into power for onsite operations.
Kroger’s anaerobic conversion system will process more than 55,000 tons of organic food waste into renewable energy annually and this will power the over 650,000-square-foot distribution center.
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The system will provide enough renewable biogas to offset more than 20% of the energy demand of the company’s food divisions.
Food waste is one of the least recovered materials in the municipal solid waste stream—yet it is simultaneously one of the most important materials that need to urgently be diverted from landfills. Food dumped in landfills decomposes to create methane, a potent greenhouse gas that contributes to climate change.
According to a UN report, “Food Wastage Footprint: Impacts on Natural Resources”—a shocking 1.3 billion tons of food is wasted or lost globally each year. This is equal to one-third of all food produced around the world. The result is massive economic loss and alarming damage to natural resources and the environment.
The direct cost to producers of food that goes to waste is currently US $750 billion annually worldwide, a figure that excludes wasted fish and seafood, the report states.
Diverting even just a portion of this to waste-to-energy (WTE) systems could free up large amounts of landfill space, while at the same time potentially powering vehicles and heating homes and factories.
Perhaps that’s why WTE is one of the fastest-growing segments of the global energy sector.
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Currently, there are some 800 industrial-scale WTE plants in more than three dozen countries around the world, and likely thousands of smaller systems at individual sites.
Aside from anaerobic conversion, which appears to be a bit off-putting due to the odors that float around these treatment plants, many companies are using heat to break down food waste into fuel and chemicals in what is known as thermal processing.
Thermal processing may turn out to be easier and more efficient than anaerobic conversion because it has the ability to handle all types of food waste.
By. Joao Peie of Oilprice.com