UNC considering using torrefied pellets in place of coal

_CORRECTION: Due to a reporting error, the original version of this story incorrectly attributes a statement that the University had postponed maintenance for about 20 buildings to Stewart Boss. The statement came from a PowerPoint presentation provided to the reporter. The Daily Tar Heel apologizes for the error. _

The next step towards a coal-free UNC might be a risky one.

While the University awaits the results of wood pellet tests from the spring, it has started to consider torrefied wood pellets.

This type of pellet produces more energy, but the market might not be able to provide the quantity UNC needs.

The University’s Department of Energy Services issued a bid June 13 for contracts to supply UNC with torrefied wood pellets for tests in September, said the department’s director Ray DuBose.

Torrefied pellets have energy output levels similar to those of coal, which are higher than the those of regular pellets.

The torrefaction process exposes pellets to heat, which removes moisture from the pellets and makes them easier to burn.

In addition to having higher energy output than regular pellets, torrefied pellets can be transported in uncovered rail cars. Normal wood pellets cannot, an inability that posed a problem for would-be suppliers in the spring.

Another difference between the types of pellets is that regular pellets are found in North Carolina and Virginia, but torrefied pellets have not been produced on the scale needed for testing.

“We do not even know that this material is available today,” DuBose said.

Chris Hopkins, a research assistant at N.C. State University who studies biomass, said torrefied pellets might not be available in time for UNC’s goal of tests in September.

Commercial-scale torrefied wood production only recently became available in Europe, and similar facilities will not open in the United States until December, he said.

“I’m not sure how UNC is going to fill their torrefied wood order,” he said.

DuBose said the University discussed torrefied wood with suppliers who confirmed they would be able to deliver pellets on time in the quantities UNC desires.

The spring tests had been scheduled for last fall, but were delayed when the initial supplier was unable to deliver its order.

UNC is testing biomass in order to find an energy source to replace coal by 2020.

Stewart Boss, co-chairman of the Sierra Student Coalition, said the group plans to monitor the torrefied wood pellet tests to make sure UNC is conducting the tests in an environmentally friendly manner.

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