Mike Smith wants to bring the green energy revolution to Vineland. He plans to take the world’s fastest growing plant and make it grow even faster. Then burn it to create a natural gas and transform that into energy.
Smith and his financial backers have invested about $300,000 so far in a leaf called duckweed that grows on ponds around the world. Working in a lab behind his farmhouse in Hamilton Township, his team at Ceres Energy Group has developed aquaculture and combustion technologies they say make this particular biomass far more profitable and reliable than other biomass energy sources. They hope to sell the Vineland city government on their idea, because they think duckweed can be the pioneering renewable energy source that city officials have sought in their energy expansion plans.
“Right now, it’s a big solar battery,” said Smith, who also runs Mother Earth Energy, a biodiesel company based in Chester, Pa. “It pulls in energy from the air, the sun, the water. The question is, how do you pull the energy out of this battery?”
Last year, scientists at North Carolina State University found duckweed produces five to six times as much starch per acre as corn, which is key because the starch is what’s used to create ethanol.
Nearly two years ago, the Department of Energy’s Joint Genome Institute linked up with Rutgers University researchers to sequence duckweed genetics to gauge the plant’s potential as a biofuel and wastewater cleaning agent. Joachim Messing, director of the Waksman Institute of Microbiology at Rutgers and a researcher on the Duckweed Genome Project, called duckweed “a perfect photosynthetic machine.”
Scientists say duckweed can be turned into a fuel, just like any other biomass can.
“There are a million plants out there from which you can make intermittent biofuels,” said Adam Sherman, project manager with the Biomass Energy Resource Center in Vermont.
Whether it’s corn, wood, switchgrass, manure, earthworms or duckweed, it all can be burned to become fuel, natural gas or even power, scientists say.
“The question isn’t whether it’ll work,” said Norman Smit, a spokesman for the Biofuels Center of North Carolina, a state-funded initiative to study prospective biofuels. “It’ll work. The question is whether it’ll be price-competitive.”
Smith’s team thinks they’ve found a way to grow enough duckweed to make it profitable. They’ve increased the growth rate of what Messing said is already the world’s fastest growing plant.
Several studies, such as a 2000 study published in the Journal of Arid Environments, found that increasing the level of carbon dioxide in the atmosphere from 450 parts per million to 550 parts per million would accelerate plant growth by more than 30 to 40 percent.
Ceres aquaculturist Ned Gaine has jacked up the carbon dioxide levels in the Ceres aquaculture facility to 3,000 parts per million, increasing the thickness of the duckweed leaves from about one-eighth or one-quarter inch to one inch. He’s also using four duckweed species native to the New Jersey area to diversify his samples and determine what combinations grow most quickly.
“We’re the only guys studying intensive aquaculture to speed it up,” Smith said.
“We feed this plant enormous amounts of (carbon dioxide), which is coming from the stack,” Smith said. “This is our secret sauce, jamming (carbon dioxide) down this plant’s throat. The polyculture helps too.”
Smith, who grew up on a Weymouth Road farm in Vineland, first came across the idea at the 2008 Green Expo in Philadelphia, through a conversation Smith had with engineer Rudy Behrings. Behrings had been following experiments in transforming algae into biofuels.
“Algae grows really fast,” Behrings said. “It doubles in mass in 90 minutes, but the problem with it is it’s a single cell organism. How do you get it out of the water? Many companies have worked with it and spent millions of dollars trying to do this, and they all failed.”
Behrings had worked on desalination project with Gaine, an aquaculture biologist who worked at Rutgers’ Multispecies Aquaculture Demonstration Center in Cape May.
“Rudy approached me and said, ’What can we harvest easier than algae?’” Gaine said. “I said, ’Duckweed.’ I knew it was being aquacultured.”
Behrings brought that up in conversation with Smith, and Ceres was born.
Their process after the duckweed harvest is deceptively straighforward. First, they skim the duckweed off their indoor ponds with a device similar to a pool skimmer. They run it through a poly-phasic separator, and the kinetic nozzle pounds the duckweed into a slurry, basically blowing it apart. Then it goes into a gasifier, which turns it into one-third natural gas and two-thirds charcoal. The natural gas is collected, which can later be converted to energy. The charcoal is saved, and it fuels the internal combustion engine that runs this whole process in the first place.
“The reason why this stuff is so wonderful is it’s so clean,” Smith said. “Its waste products are carbon dioxide and water vapor. We sequester the (carbon dioxide) and feed it to the next generation of duckweed. So this is a zero-carbon event.”
Ceres has proposed growing duckweed on wastewater on Landis Sewage Authority land near Vineland’s four-megawatt solar field, a plan under consideration by Vineland city officials. Duckweed typically grows faster on wastewater because of its increased levels of nitrogen, and it’s used as a water treatment agent in India and Australia.
Smith says Ceres will need about one acre per megawatt and can produce one megawatt per $2 million of investment, a rate that includes all capital costs.
If Vineland officials don’t go for it, he plans to build a plant to convert duckweed into natural gas that would then be sold to power suppliers.
Ceres has skeptics though. Anne-Marie Stomp, one of the North Carolina researchers looking at duckweed’s potential as a biofuel, said she doesn’t think the yields will be high enough to produce enough natural gas.
“Duckweed has been seducing people for at least 100 years,” Stomp said. “It’s because it’s a tiny little plant. It grows like a bat out of hell. But it’s a plant.”
The Ceres team thinks they’ve put together something that everyone else missed.
“You have the people who know duckweed,” Gaine said. “You have the people who know biomass. You have the people who know green energy. But nobody connected the dots.
“Connecting the dots,” Gaine said. “That’s all we’re doing, connecting the dots.”