Whether it comes in the form of liquids, protein shakes, chocolate bars, or leafs of kale, food is energy. The body needs it for fuel.
Increasingly, however, food—specifically unwanted, or unused food—is proving to be a source of a different type of power: electricity and heat.
Despite all the admonitions to clean their plates, American consumers produce a huge amount of food waste. Households throwing out apple cores, cafeterias dumping unused macaroni and cheese, restaurants tossing out less-than-perfect radishes that won’t look great on the plate, espresso joints getting rid of wet coffee grounds—it’s all garbage. Some is recycled or used quickly, through programs like Share our Strength. Some goes into compost heaps. But most of it is simply carted away at considerable expense to landfills.
Harvest Power, a young start-up based in Waltham, Massachusetts, had a different vision for food waste. The firm, which was named one of America’s 50 Most Innovative Companies by Fast Company, operates three “energy gardens” (two in Canada and one in Florida) where it turns leftovers and discarded food into electricity and heat.
Founded in 2008, the company got its start by using organics—food scraps, plant waste—to make soil and fertilizer. Through 40 different sites around the U.S., the company processes about two million tons of organic waste each year. But Harvest Power believed it could use the same material to generate power. In the fall of 2010, it bought an anaerobic digestion project then under construction in London, Ontario. The system had the capacity to generate 2.8 megawatts of energy, an amount sufficient to power 1,400 homes.
How? In anaerobic digesters, organic material is mixed on a huge pot with massive quantities of tiny bacteria. As the scraps break down, the process releases biogas or synthetic gas that can then be deployed to generate both electricity and heat. As the Environmental Protection Agency notes, “one of the natural products of anaerobic digestion is biogas, which typically contains between 60 to 70 percent methane, 30 to 40 percent carbon dioxide, and trace amounts of other gases.”
Having bought one energy garden, Harvest Power next decided to grow its own. It raised several rounds of venture capital, including an impressive $100 million in April 2012, and another $15 million in July 2012.
It has plowed those funds into building out its network and constructing new energy gardens. Last September, Harvest Power opened the largest such food-to-power plant in North America, in Richmond, British Columbia. It can take up to 40,000 of detritus each year. “This facility represents the innovation, passion and commitment required to usher in the future of organics management,’ said Paul Seelew, the founder and chief executive officer of Harvest Power. The company says the Richmond plant makes enough energy to power about 9,000 homes annually in addition to producing lots of soil.
In February, Harvest Power opened its third facility in Bay Lake, Florida, near Orlando. When it’s fully up and running, this plant can handle about 120,000 of organic junk each year and “while producing 5.4 megawatts of combined heat and power,” the company says.
The beauty of the business model is that peer pressure and a desire to save money pushes area companies to supply Harvest Power with the “fuel” it needs to make electricity. The company started a public relations campaign — “Orlando or Landfill? Responsible Food Recovery” — noting that every second in Central Florida alone, some 24 pounds of food waste are dumped uselessly into landfills. In March, FreshPoint Central Florida, a huge distributor of fresh produce, struck a deal with Harvest Power. The company will take all FreshPoint’s leftover food matter—things like “fruit and vegetable peels, strawberries tops, corn husks, and pineapple cores” and plant it in its “energy garden.”
Thus far these efforts are quite small scale. But they are quite promising. Many of the fuels we use to generate electricity —natural gas, oil, coal—are abundant yet finite. It takes an extremely, extremely, extremely long time to grow new supplies. But America’s massive food and restaurant industry produces a huge amount of food scraps and waste every day—and every day the country’s highly productive agricultural system grows a new supply. Every piece of garbage that is diverted from a landfill is a penny saved. When that garbage is diverted into a vat of energy-producing soup, it becomes a penny earned.