WM's waste-based energy strategy progresses

By Anna Austin
In the midst of multiple new renewable energy investments and partnerships-most recently involving Canadian cellulosic ethanol producer Enerkem Inc., organic waste-to-biogas technology company Harvest Power Inc. and plasma gasification technology developer InEnTec LLC-"waste" is no longer an applicable term for the materials Waste Management has collected and handled for decades.

Carl Rush, vice president of WM Organic Growth Group, who directs the strategy behind WM's renewable energy investments, said the company's versatile presence in the biomass/biogas energy industry, aside from its goals of sustainability, is the key to WM's continued success. "With these investments-Enerkem, Terrabon, S4 Energy Solutions-each fills a potential niche within the recovery of material value," he said. "We are looking for those we think are closest to commercialization and have the highest likelihood of success, and we have invested with those who have met those criteria."

On WM's most recent announcement of forming joint venture company S4 Energy Solutions with InEnTec to develop, operate and market plasma gasification facilities using InEnTec's Plasma Enhanced Melter technology, Rush said the first major milestone will be to complete a 25-ton-per-day demonstration unit to prove the technology at scale. "It's been done at smaller scales, so we're proving it up at our Columbia Ridge Landfill in Oregon," he said. The unit is currently under construction, Rush added, and should be fully operational by the end of the year.

As InEnTec's technology produces syngas that can be used to make a variety of products including electricity, liquid fuels such as methanol/ethanol, hydrogen and, potentially, diesel, Carl said the products WM are focusing on are categorized into a value hierarchy the company has developed. "Electricity is the base case for outputs; the next level up is liquid fuels, which we are developing some of right now, and the next level up is the specialty chemicals and higher value products," he said. "Syngas has a lot of flexibility, so it becomes a function of how efficient and how effective the conversion technology is that you put on the back end."

WM also recently invested in organic waste-to-biogas company Harvest Power. "We made an investment, but what really intrigued us about Harvest Power was that they are pursuing biogas as an output of their technology, but also recognize that there may need to be first steps taken in the composting arena in order to get into the game," Rush said. Ideally, the relationship will extend beyond an investment, he added, and WM and Harvest Power are jointly looking at projects in the composting and anaerobic digestion sectors.

The same goes for WM's investment in Enerkem, which is currently operating a commercial-scale syngas-to-ethanol/methanol plant in Westbury, Quebec, and is constructing a 20 MMgy waste-to-biofuels plant in Pontotoc, Miss. "At this point it's an investment, but it's a different type of syngas technology than S4 Energy Solutions," Rush said. "We're keenly interested in what they are doing and are looking for opportunities to do things jointly with them while we watch their development, understand their technology and see what they can accomplish."

WM is well on its way to meeting its goal of generating the renewable energy equivalent of powering 2 million homes by 2020, added Wes Muir, WM director of corporate communications. When WM announced its goal in 2007, it generated enough renewable power for 1 million homes, he said.