Seacoast NRG

Public Service of New Hampshire announced yesterday that its new wood-fired power plant at Schiller Station in Portsmouth is now online and generating power.  As part of its Northern Wood Project, PSNH replaced one of its three, 50-megawatt coal-fired boilers at Schiller Station with a new wood-burning boiler of the same size.  The new boiler burns wood chips harvested from forests in New Hampshire.  PSNH claims that overall emissions from the Schiller Station plant will be reduced by more than 380,000 tons annually.

Schiller Station is PSNH’s oldest fossil fuel plant, having begun operation in 1949.  The plant has been updated several times to reduce plant emissions, particularly to control the emission of nitrogen oxides.  In this lastest upgrade for the $75 million Northern Wood project, PSNH claims that compared to the coal boiler it replaced, the new boiler will reduce nitrogen oxides emissions by 70%, mercury emissions by 90%, sulfur dioxide emissions by 95%, and greatly reduce particulate emissions. 

With regard to carbon dioxide emissions, it is true that burning wood is often considered to be carbon-neutral, since the carbon emitted has been recently sequestered, and the regrowing of trees will supposedly re-sequester the released carbon (I would argue with this belief btw:  letting a tree fall and rot into the ground clearly seems carbon neutral; felling a tree and completely burning it’s biomass does not.)  What is even less clear is the environmental impact of the transportation required to fuel the new boiler.  The coal consumed by Schiller typically arrives by ship, wherea the wood chips are brought to the plant in trucks–50 or more truckloads per day.