Solar Ready CCR Site Closures Help Energy Companies Move Toward a Sustainable Future
Electricity is the one big energy source that can be free of carbon emissions. You can make it from the sun. You can make it from the wind. Tap the heat of the Earth, hydropower. While all utilities are moving in a sustainable, environmentally friendly direction, Aliant Energy stands out for making progress and keeping rates reasonable for consumers.
At the recent USWAG Workshop on Decommissioning, Repurposing & Expansion of Utility Assets held October 2019, Eric Nelson presented on the opportunities for solar generation at closed CCR sites and provided an overview of civil and geotechnical considerations when redeveloping closed sites as solar generating assets. His presentation demonstrated these considerations through the use of a case study.
SCS Engineers has assisted Alliant Energy with the design and/or construction of multiple coal combustion residual (CCR) surface impoundment closures. Two of the completed closures are the former Rock River Generating Station in Beloit, Wisconsin, and the M.L. Kapp Generating Station in Clinton, Iowa.
Both sites were closed by incorporating Alliant Energy’s vision to create “solar ready” sites. The Rock River site is now home to just over 2 megawatts (MW) of solar photovoltaic (PV) generating capacity, which was developed on the footprint of the now-closed on-site landfill and ash ponds. Although no solar assets have been developed at the site, the M.L. Kapp ash pond closure represents another opportunity for Alliant Energy to repurpose a closed ash pond for clean power.
Two additional closure designs are in process that incorporates similar elements, making them available for future solar generating asset development.
Eric J. Nelson, PE, is a Vice President of SCS Engineers and one of our National Experts for Electric Utilities. He is an experienced engineer and hydrogeologist.
Even the simplest impoundment closures come with design challenges. It is a challenge to navigate project constraints, whether technical, regulatory, or financial, to design and implement an effective closure strategy. Cost often helps to determine the “balance” between project constraints when the future end use of a closed CCR surface impoundment or the property it occupies is undefined. When a post-closure end use is defined, finding balance among project constraints to best serve that future use provides rewarding challenges.
SCS Engineers has navigated this balancing act on impoundment closure projects during generating facility decommissioning. Through a presentation of case studies, you can learn how this team has approached ash pond closure planning and execution where the future use of the impoundment site ranged from undefined to the home of a new solar photovoltaic installation. Examples also include potential future industrial use or property sale.
Case studies will highlight how geotechnical, hydrological, regulatory, or simple physical constraints have influenced the design and implementation of CCR surface impoundment closures.
EUEC 2019 in San Diego, February 25-27, 2019. Conference details here.