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Minnesota Power (MP), based in Duluth, Minnesota provides electric services to around 144,000 retail customers, and about a dozen large industrial enterprises in northeast Minnesota. The majority of the power at Minnesota Power is generated from low-sulfur, low-mercury coal from the Powder River Basin. Faced with ever-more-stringent emission regulations at the state and federal level, the company initiated a $240 million project in 2006 to reduce emissions from the 350 megawatt Boswell Energy Center Unit 3, company’s second largest generation unit.

Building a Greener Future at Minnesota Power, USA
In this video: Al Rudeck, Vice President of Generation at Minnesota Power gives overview of Minnesota Power
and explains the project with Hitachi Power Systems America. (0:47) (interviewed in February, 2011)

Hitachi Power Systems America (HPSA) provided a comprehensive technology solution that helped Minnesota Power meet their lower emission targets as the part of aggressively scheduled three-year project. The retrofit package from Hitachi Power Systems America included Selective Catalytic Reduction system and Wet Flue Gas Desulfurization system.

Helping Minnesota Power Meet Emission Targets, USA
In this video: David Paz, Regional Sales Manager at Hitachi Power Systems America discusses the relationship
with Minnesota Power and the process in working with Minnesota Power on their Boswell Unit 3.

Hitachi Power Systems America successfully constructed and tested the Minnesota Power’s retrofit project, which resulted in a 99 percent reduction in sulfur dioxide (SO2) emissions and a 92 percent reduction in nitrogen oxide (NOx) emissions.

*Source: Minnesota Power

Go through the next sections of Hitachi case studies to get detailed information on how Hitachi Power Systems America helped Minnesota Power (MP) to meet the emission regulations for their Boswell Energy Center Unit 3.

Minnesota Power (MP)


Products & Services
Selective Catalytic Reduction (SCR) system, Flue Gas Desulfurization (FGD) system

Power generation

Release Date
May, 2011, prior to Hitachi Power Systems America’s business transfer to Mitsubishi Hitachi Power Systems

Solutions By
Hitachi Power Systems America, Ltd.


Minnesota Power’s Challenge

Minnesota Power (MP) commenced a proactive emissions reduction project at the Boswell Energy Center Unit 3, with aim to reduce emissions of sulfur dioxide, nitrogen oxides, particulate matter, and mercury, in advance of the implementation of new environmental emission regulations. Minnesota Power needed the support of technology suppliers, engineers, and construction contractors, and looked for a technology supplier to help complete their mission.

Minnesota Power Emissions Reduction Project P1 USA
In this video: Al Rudeck discusses the complexity and proactive decision to embark on
Boswell Unit 3 emissions reduction project, including decision of choosing HPSA for project. (1:15)

The Mission

For the Boswell 3 plant, Minnesota Power commenced a proactive project to reduce sulfur dioxide emissions by 99 percent, nitrogen oxide emissions by 92 percent, mercury emissions by 95 percent, and particulate matter by 95 percent.

They determined that their project scope would include the following Air Quality Control System equipment:

  • Low Nitrogen Oxide [Low NOx] Burners
  • Selective Catalytic Reduction System [SCR]
  • Carbon Injection System
  • Pulse Jet Fabric Filter
  • Wet Flue Gas Desulfurization System [WFGD]

MP sought support of several technology suppliers, who could achieve the project emission goals. Through a competitive solicitation process, Hitachi Power Systems America offered a solution, which included the SCR system, WFGD system, and interconnecting ductwork as a comprehensive system, along with a complete set of guarantees for their entire supply.

The state-of-the art technology of Hitachi Power Systems America stood out from the competition. Being at the forefront of SCR technology innovation and a world leader of SCR systems and NOx catalyst, HPSA was uniquely positioned in the power generation industry as a provider of complete coal-fired SCR systems, featuring their proprietary plate type catalyst and patented SCR reactor hood.

Minnesota Power Emissions Reduction Project P2 USA
In this video: Tom Coughlin, Project Manager, Minnesota Power, shares goals for the project,
importance of selecting the right partner to achieve success, and how this was achieved.
(0:41) (interviewed in February, 2011)

Minnesota Power established an aggressive three-year schedule for the execution of complete emission reduction project, and the commitment done by Hitachi Power Systems America to meet this schedule strengthened their selection for the project team.

Minnesota Power Emissions Reduction Project P3 USA
In this video: Tom Coughlin shares challenges faced and collaboration with Hitachi Power Systems America,
and views on Hitachi as a technology solutions provider. (0:26)


Hitachi Power Systems America’s Solution

Hitachi Power Systems America provided a comprehensive package of equipment to Minnesota Power that included a Selective Catalytic Reduction (SCR) system, a Flue Gas Desulfurization (FGD) system, and an interconnecting ductwork.

Both HPSA systems incorporated vital components to resolve MP’s challenge, and included following:

SCR system

  • Design based on a physical flow model of the flues, inlet hood and reactors that promote uniform distribution of flue gas to enhance performance and avoid ash plugging.
  • Patented reactor hood eliminates the need for turning vanes that can cause accumulation of ash on the catalyst.
  • HPSA’s proprietary phosphorus-resistant catalyst, specifically designed for Powder River Basin applications.

FGD system

  • Design based on computer and physical flow models of the absorber vessel, along with internal components for high efficiency operations.
  • Single absorber vessel constructed with corrosion resistant alloy to treat 100% of the flue gases emitted from the unit.
  • Hitachi-tested internals and auxiliary components for delivering reliability, long life, and ensure trouble free operation.

Reducing Emissions at Minnesota Power, US Part 1
In this video: David Paz discussed Hitachi Power Systems America’s technology expertise
and proprietary Catalyst design. (1:09)

To meet the aggressive project timeline, a collaborative effort between Hitachi Power Systems America, Minnesota Power, and their engineering & construction contractors was crucial.

Reducing Emissions at Minnesota Power, US Part 2
In this video: Don Miller, Site Construction Manager, Hitachi Power Systems America,
shares challenges and collaboration between Hitachi Power Systems America and Minnesota Power
during the 3-year project. (0:49) (interviewed in February, 2011)

Hitachi Power Systems America brought together a highly experienced project team that included project director, construction manager, procurement specialists, engineers, and others. Together, they executed the design and procurement effort in a timely manner to support the project construction and start-up schedule. Constant interaction between HPSA and the MP team in an open and cooperative atmosphere ensured success of this complex retrofit project.

Reducing Emissions at Minnesota Power, US Part 3
In this video: Tom Geiselman, Lead Mechanical Engineer, Minnesota Power,
who worked closely with Hitachi Power Systems America,
discusses aspects of the project and engineering process. (0:34) (interviewed in February, 2011)


Result & Benefits

After the construction completed in November 2009, Boswell Unit 3 resumed operations and carried out performance tests by February 2010.

Achieving a Cleaner Future in Minnesota, US Part 1
In this video: Rick Fannin, Operations Superintendent, Minnesota Power,
discusses highlights of project and performance testing following completion of the project and success
achieved through various upgrades made to Boswell Unit 3. (1:01), (interviewed in February, 2011)

Results & Benefits

Minnesota Power surpassed all of its emissions goals with the following results:

  • Emissions of sulfur dioxide (SO2) reduced by 99 percent
  • Nitrogen oxides (NOx) emissions reduced by 92 percent

*Source: Minnesota Power

Achieving a Cleaner Future in Minnesota, US Part 2
In this video: Al Rudeck shares results on emission reduction and benefits to the community
after successful completion of the project. (0:43)

The operation of the equipment supplied by Hitachi Power Systems America met all expectations, while the follow-up inspections confirmed the equipment to be in proper working condition.

As a total solution provider, HPSA has continued to support and serve Minnesota Power through its Aftermarket Group for Boswell Unit 3 and its future AQCS (Air Quality Control System) needs.

Achieving a Cleaner Future in Minnesota, US Part 3
In this video: Tom Coughlin shares future collaboration
planned with Hitachi Power Systems America. (0:31)

About Hitachi Power Systems America

Hitachi Power Systems America, Ltd. (HPSA) is a wholly owned subsidiary of Hitachi America, Ltd. HPSA provides engineering, procurement, and project management services associated with boiler, turbine, and Air Quality Control System (AQCS) requirements for new plants and retrofit applications.

As a part of Hitachi’s evolving strategy, Hitachi Power Systems America focuses on the growth in regional markets to improve existing facilities and Greenfield installations in the North American Power Market. Hitachi recognizes US as one of the largest consumers of electricity in the world, and commits to support the growth of the industry with its outstanding portfolio of products and services. The stable price and ample supply of coal is creating brisk demand for new plant construction. Stringent environmental standards are stimulating demand for the retrofit type of products that form a part of Hitachi's core competency.

Hitachi Power Systems America also houses the Company’s Global Center of Excellence for the Power Emissions Market, including Wet Flue Gas Desulphurization, Selective Catalytic Regeneration, Catalyst Sales, and Total Air Quality Control Systems Solutions.

HPSA is based in Basking Ridge, NJ, and has an experienced staff that possesses a broad-based background in power generation and pollution control practices. Henry Bartoli heads the company as President and CEO. Earlier, he had served as Executive Vice President of the environmental businesses of Hitachi America, Ltd. - Power and Industrial Division.

Customer Profile

The Minnesota Power (MP), based in Duluth, provides electric service to around 144,000 retail customers and about a dozen large industrial enterprises in northeast Minnesota. Its largest asset is the Boswell Entergy Center, a coal-fired plant in Cohasset, Minnesota, which has a total power output of over 1,025 megawatts (MW) from four units.