A renewable energy source doesn’t have to be any farther than a garbage can. Just ask Paul Sellew, cofounder and CEO of Harvest Power, an odd but innovative addition to the energy sector. “Unlike wind and solar energy, which are intermittent, we produce renewable energy 24/7.” Harvest Power makes energy by using anaerobic digestion to break down organic material such as food scraps, grass, and brush into biogas, a mixture of methane and carbon dioxide, which can be used to produce electricity—at any time.

Paul Sellew explains how to make energy from trash

What is Harvest Power’s renewable energy made from? Food waste from grocery stores, restaurants, and industrial food processors, as well as leaves, grass, and wood brush.

What’s the process? Anaerobic digestion, in which microorganisms break organic matter into methane and carbon dioxide, which can then be turned into electricity.

Why create power this way? The EPA estimates that between 30 and 35 million tons of food waste is generated in the US each year. That waste could be used to create clean, renewable energy to power homes and other buildings.

Sellew started Harvest Power in 2008 with Nathan Gilliland, an industry executive who formerly managed $2 billion in utilities, power generation, and consumer product investments. “We felt that throwing organics out as waste materials was something that should change,” Sellew says. “We were dedicated to taking materials and repurposing them to higher and better uses.”

Although all businesses are potential organic material providers, certain businesses, such as grocery stores, large restaurants, and industrial food processors, are particularly good candidates. The company also sells the nutrient-rich mulches, fertilizers, and soil by-products created during the process to professional landscapers and homeowners.

Relying on a landfill-based waste-management system is a short-term solution to disposal and energy-source problems, Sellew says. “Those materials, from a value standpoint, are lost forever,” he explains. “The notion of putting waste on a truck and driving miles to a landfill, putting it in a hole, and covering it does not make sense.”

Just a few months ago, Harvest Power opened two commercial-scale ‘Energy Gardens’—one in Richmond, British Columbia, and one in London, Ontario. The London facility processes 65,000 tons of organic materials per year; the Richmond facility processes 40,000 tons from both businesses and private residences to help power Vancouver-area homes.

Sellew says most countries are taking their cues from Germany, which has been an anaerobic digestion pioneer. “Germany has created a good road map with the development of its renewable energy industry,” he says, “and to a large degree, the US has followed it.” With good reason. “By the EPA’s own admission, 30–35 million tons of food waste is generated each year in the US,” Sellew says. “Add in leaves, grass, and wood brush, and that’s 40 million tons per year of materials that can be repurposed to make energy.”

In 2011, Harvest Power was named to the Global Cleantech 100 list, produced by the Cleantech Group and the United Kingdom’s Guardian News and Media. The list denotes the top private clean-energy companies—who provide environmental technologies or processes that offer competitive returns for investors and customers—that are poised to make the most significant impact in the next five to ten years. Power to ’em.