Whole Trees 90% of Rothschild, WI Biomass Incinerator Fuel

- by Kevin Murphy, February 26, 2014. Source: Wasau Daily Herald

[[{"type":"media","view_mode":"media_large","fid":"169","attributes":{"alt":"","class":"media-image","style":"width: 333px; height: 221px; float: left; margin-left: 10px; margin-right: 10px;","title":"Photo: Corey Schjoth"}}]]The recently built power plant at Domtar paper mill is getting only 10 percent of its fuel from logging waste, which originally was supposed to supply nearly all of the plant’s energy needs.

The 50-megawatt, $255 million power plant went online in November to provide steam for Domtar’s paper operations and a clean source of power for WE Energies. The plant will burn 500,000 tons of biomass annually, said Cathy Schulze, a WE Energies spokeswoman.

WE Energies told the Wisconsin Public Service Commission in its permit applications, which were required to build the facility, that logging waste would supply the vast majority of the plant’s fuel. The PSC approved the plant’s construction over the objection of neighbors and critics in the wood industry who said forest waste would not provide enough fuel for the operation and that the plant inevitably would drive up wood prices.

The first months of operation have proven critics might have been right, as the plant has turned to new sources, including freshly cut trees, for fuel.

“We fully expect this trend to continue, especially in light of the likely spread of the emerald ash borer,” Paul Farron, WE’s manager of strategic issue, wrote to the PSC on Friday in a document obtained by Daily Herald Media.

The emerald ash borer is a bug that has decimated millions of ash trees across the Upper Midwest. It now has moved into Wisconsin and is creeping toward the Northwoods, which is where much of the biomass fuel was to originate.

Domtar initially targeted tree tops and other logging waste as its anchor fuel for the power plant, said Jeff Plunkett, the company’s procurement manager. Instead, wood from land cleared of trees for expanding farms and housing developments and residue from saw mills and paper mills has been a “huge source for us,” he said.

“It’s been a pleasant surprise not to have to go into the woods for biomass,” said Plunkett, because wood residue is more expensive to procure than the sources it is now using.

Plunkett said he can’t predict where the plant will get most of its fuel in the future, but he is satisfied with the track that has been established in the first several months of operations.

“We won’t change if we don’t have to. The flow of material is there and we believe that 500,000 tons a year is an amount we will reach and consume on an annual basis,” he said.

Assessing the impact of biomass harvesting is a responsibility WE Energies took on when it received PSC approval to build the plant at Domtar. It is asking PSC approval for two studies after polling Wisconsin Council of Forestry members and Biomass Harvesting Guideline Advisory Committee members.

One study, a scrub oak assessment, would identify the range of those trees and their age within Domtar’s 23-county procurement area. In Farron’s letter to the PSC, scrub oak was identified as “ideally suited for biomass harvesting,” because it yields few logs or pulpwood, has drawn little commercial interest, and regenerates through clear cutting.

The other proposed study would assess guidelines for biomass harvesting sites. There are little data on what occurs to a site after a biomass harvest. The study would include 10 “in-woods” assessments of biomass timber sales in Domtar’s procurement area to assess impacts on streams and wetlands, rutting, regeneration, tons taken per acre and soil samples to determine various nutrient levels.

The studies would cost $30,000, would be managed by Domtar staff and the results would be shared with members of the Wisconsin Council on Forestry and the Biomass Harvesting Guideline Advisory Committee.