Briefing Highlights One Possible Solution to Growing Problem of Food Waste | Article

The Environmental and Energy Study Institute (EESI) and the American Biogas Council (ABC) recently held a briefing about the numerous challenges posed by the 17 million tons of organic wastes produced in the United States each year — to human health, water and air quality, and to communities that must manage these wastes. The briefing focused on how anaerobic digestion offers solutions to many of these pressing issues, especially the growing issue of food waste.

Companies and individuals who are turning waste management challenges into opportunities in their communities spoke about how they are using biogas systems at farms, landfills and wastewater treatment plants to deliver both environmental and economic benefits to their communities. However, despite these successes, the United States is improperly disposing of most of its organic wastes, contributing to climate change as well as degraded water and air quality.

The most glaring waste issue in the United States is food waste. Both the U.S. Department of Agriculture (USDA) and Environmental Protection Agency (EPA) report that about 40 percent of U.S. food is needlessly wasted. This translates to more than 38 million tons of food waste in 2014, according to the EPA. In a country where 16.5 percent of households with children are “food insecure,” the issue of food waste is especially gut-wrenching. Only five percent of that waste was diverted from landfills and incinerators. Currently, food waste makes up a larger share of landfills than any other kind of material.

The USDA and EPA have set a goal of reducing food waste by 50 percent by 2030, through source reduction, redirecting usable food to the hungry and recycling inedible food waste through composting and anaerobic digestion. However, even if edible food waste is greatly reduced, there will still be numerous sources of non-edible wastes, such as food processing waste and spoiled food, not to mention manures and human wastes. Adding food waste to existing biogas systems makes great environmental and economic sense, yet is still not widely deployed.

A recent EPA report shows that as of 2015, there were only 154 biogas systems processing 12.7 million tons of food waste a year. For comparison, the same number of digesters processed 2.2 billion gallons of liquid wastes, mainly at waste water treatment facilities (These numbers are likely somewhat higher in reality, but are based on survey response rates—137 of the 154 facilities responded to the survey). California boasts the highest number of biogas systems (30), with Wisconsin second (17), and New York and Ohio tied for third (13). As of 2015, fifteen states still had zero digesters.

There are tremendous benefits to digesting food waste, either at stand-alone facilities or comingling food waste with other wastes within biogas systems. At the ABC-EESI briefing, the benefits of comingling food waste with other wastes were discussed. If municipalities ban food waste from landfills, biogas system owners, like farmers and waste water treatment facilities, can generate additional revenue by accepting food waste. Co-digestion of food waste and biosolids (human waste) or manure also creates more end-products and a more efficient system than a single-stream digester.

To tackle the growing issue of food waste, several states have instituted mandatory organics recycling, with California being the largest state to do so. Clarke Pauley, of CR&R, operator of North America’s largest biogas system, discussed how his waste management company is utilizing food waste to create fertilizers and renewable natural gas that it uses to run its fleet of near-zero emission trucks. The organics recycling law in California is providing the financial incentive for organics recycling and biogas to thrive in the state.

Both Bryan Sievers, of Sievers Family Farms, and Chris Peot, of D.C. Water, discussed the benefits of comingling food waste with the wastes their facilities are already processing. Sievers explained they started off just using manure from their farm, but now they incorporate local food waste, chick hatch waste, meat production and processing waste, and waste from local ethanol and diesel production into their plant. Food waste has brought their biogas system’s production up from around 40 percent capacity to 100 percent capacity. Additionally, they harvest their cover crops and add them to their digester, instead of killing them with an herbicide.

According to the American Biogas Council, there are currently 2,000 operational biogas systems in the United States. Some are in wastewater treatment facilities, some are on farms, some are in landfills, and a few only handle food waste. ABC sees the potential for 13,000 more biogas systems in the United States. Those 13,000 new systems would require $40 billion in new capital investment, and create 300,000 construction jobs and more than 20,000 new, permanent long-term operational jobs.

By Tim Manning and Jessie Stolark

For more information see: