What is the scrubber and how does it affect you?
Issue Facts

By: Ken Colburn, Symbiotic Strategies, an independent consultancy providing assistance to states on issues relating to climate change, and Mary Beth Walz, state rep. from Bow (with subsequent updates by LFDA editors).
In 2006, after negotiations among representatives from the Legislature, PSNH and various environmental groups, New Hampshire enacted a law requiring PSNH to install pollution control technology known as a scrubber to reduce by 80% emissions of mercury at its coal-burning Merrimack Station in Bow, NH. In 2006 the cost of the scrubber was estimated to be $250 million.
By late 2008, however, the cost had nearly doubled to $457 million. There is the prospect of federal requirements to reduce climate-altering carbon dioxide emissions through some form of carbon pricing during the expected life of the plant. Some people estimate that carbon fees could significantly increase the cost of electricity from Merrimack Station during its projected life. Also, it is possible that additional pollution abatement requirements will be mandated in the future.
State authorities approved the scrubber project and construction began in March 2009. In 2009 certain commercial ratepayers asked the N.H. Public Utilities Commission (PUC) to review the scrubber cost increase. The PUC’s authority is established and limited by state law. The PUC declined to review the costs of the scrubber before the project is completed, when it will conduct a prudency review of costs incurred. The PUC based its decision on the basis that state law mandated that the scrubber be constructed. The commercial ratepayers appealed the PUC’s decision to the NH Supreme Court. In August 2009 the court rejected the appeal on the basis of standing; ratepayers haven’t yet been charged for the scrubber. The commercial ratepayers also advocated for a law requiring a far-reaching study related to the scrubber, but the law was not enacted. Challenges by environmental advocates and merchant power generators, some of whom would like to see the plant retired, have subsequently been lodged under federal and state statutes and regulations.
In November 2011, PSNH said the scrubber would come in $35 million under budget, chalking up the savings to a dip in the cost of materials and lower-than-anticipated construction costs. The total estimated project cost shrunk to $422 million for the scrubber, which started operating in September 2011, but won't be fully operational until 2012 or 2013. New Hampshire Business Review in November 2012 called the scrubber "a major contributor to PSNH's preliminary estimate of a January rate increase from 7.11 cents per kWh, to 8.97 cents." The sentiment was subsequently confirmed by PSNH spokesman Mike Skelton, speaking with New Hampshire Public Radio.