It looks like coal; it burns like coal; in some ways, it even behaves like coal. But at it's core, all it is is ordinary, everyday wood.
Poplar trees could help power the Michigan State University campus, if a proposal is approved, by harvesting their wood and changing its form into pellets that jive with the setup of university's current coal plant.
"We're trying to increase the level of renewability of the electrical power that we produce," said Chris Saffron, an assistant professor in MSU's Biotechnology and Agricultural Engineering Department. "So yes we're trying to make our power plant more green."
To turn wood to pellets, Saffron says the simplest way is to use a process called torrefaction. Wood is heated without oxygen, weakening it. That makes it easier for it to be ground into a powder form.
The ground powder is then put into a machine that packs it into small pellets, for optimization purposes.
Picture two dump trucks: one filled to its limit with powder, the other with pellets. Though they take up the same amount of space, the pellets are more dense, which means they are able to provide more energy. Simply, pellets give you more bang for your buck.
"It's like upgrading the biomass to a form that is more easily burned by your power facility," Saffron said. "The material we're producing burns just like coal burns. It's heating value is similar to coal's. It's grindability is similar to coal's. You can store it outside in a pile like you can coal. So it looks like coal and it burns like coal."
Coal is cheaper, but torrefied wood is cleaner, Saffron said.
As for the source of the wood, MSU plans to plant ten-acre plots of poplar trees yearly for six years. Each crop takes six years to grow, meaning after all the fields are planted, MSU could count on a ten-acre harvest year after year.
But MSU says it needs more wood than it can produce on its own. If the proposal were to be approved, Saffron says the school would look to private landowners for help.
Saffron says MSU's pursuit of green technology can only help the school and its community.
"It certainly makes our energy more green," he said. "But it's really more of what the university can do for everyone else. We're demonstrated a technology that could be adopted commercially in the near future."