Alliant Energy Corp. has turned its state-of-the-art natural gas-fired Marshalltown Generating Station in Iowa into a model for environmental and economic development success.
The $700 million, 650 MW combined-cycle baseload facility, which is sited on Alliant’s former coal-fired Sutherland Generating Station, is the biggest project in the Marshalltown area (pop. 27,552) in more than 20 years, bringing local jobs and growth.
Alliant retained HDR Inc., an architectural, engineering and consulting firm, to come up with the specifications for the cutting-edge plant. Once it was completed, Washington, DC-based Institute for Sustainable Infrastructure (ISI) honored the facility with the Envision Platinum award for its "significantly reduced" environmental footprint.
The Envision award is based on sustainable infrastructure criteria conceived by ISI with help from the Zofnass Program for Sustainable Infrastructure at the Harvard University's Graduate School of Design.
"Envision definitely helped our project team design and deliver more sustainability and economic benefits in the development of the Marshalltown facility," said Alliant President Doug Kopp.
He cited help in adding sustainable features to construct and site the plant, as well as advance “clean” energy use while reducing the environmental footprint.
Under the Envision criteria, the Marshalltown plant was graded in five categories: quality of life, leadership, natural world, resource allocation and climate/risk.
"These key areas contribute to the positive social, economic and environmental impacts on a community," an Alliant spokesperson said.
As the largest local development project in more than two decades, the power plant created jobs in all phases of its development, from design to start-up, averaging 650 personnel during construction. Forty percent of the jobs were filled by local residents.
"These new jobs brought significant revenue to local businesses, and the completed generating plant now employs 20 permanent employees,” the spokesperson said.
Along with also bringing millions of dollars in added local tax revenue, a new transmission pipeline links the plant to an existing Northern Border Pipeline Co. interstate line sized to handle future population growth.
"Improving the natural gas delivery system in the city also will lower the long-term delivery cost for gas to the community, saving residents and businesses an estimated $1 million annually," the spokesperson said.
In terms of addressing risks, Alliant completed an assessment of resource demands and supplies, as well as vulnerabilities for resources and infrastructure. As a result, the plant was designed to be "resilient and adaptive to potential changes," according to ISI.
Both the nearly completed Marshalltown station and the soon-to-be-started gas-fired Riverside Energy Center in Beloit, WI, are examples of how Alliant said it is modernizing generation.
Riverside, a 700 MW, combined-cycle gas-fired station, is sited on a large property that formerly included Alliant’s coal-fired Rock River Generating Station. Riverside is designed to power more than 500,000 homes and include a 2 MW solar facility to offset the gas station’s auxiliary power needs.
The construction of gas facilities in Marshalltown and Beloit creates “a multi-year boost to the local communities with hundreds of construction jobs,” Alliant noted.
Alliant, a public utility holding company headquartered in Madison, WI, provides customers in the Midwest with regulated electric and natural gas service, the company’s primary focus.
As the company’s growth platform, Alliant’s utility business is the primary target of future capital investments. The utility business consists of Interstate Power and Light Co. and Wisconsin Power and Light Co., subsidiaries that provide services to about 960,000 electric and 410,000 gas customers in the Midwest.