Frequently Asked Questions about Sundog
What is envisioned on this site?
300–400 MW solar array, ideally manufactured by Heliene in Mountain Iron, Minnesota. Heliene’s recently upgraded plant has the capacity to build 550 MW of solar panels per year.
Wind turbines
Iron-air battery and/or other forms of energy storage. Form Energy is already piloting their iron-air battery in Cambridge, Minnesota. This type of battery relies on large cells of iron pellets (Minnesota-mined iron could be used) and produces a battery with 100+ hour life. Other options include producing green hydrogen with excess electricity and pumped hydro storage in abandoned mine pits.
Using carbon-free electricity from solar, wind and hydro, Minnesota mines and steel companies would be able to create a supply chain that creates carbon-free steel in northern Minnesota. This approach can draw on similar projects, such as the Bighorn Solar/EVRAZ steel plant in Pueblo, Colorado and SSAB’s HYBRIT carbon-free steel plant in Lulea, Sweden.
Who owns the site?
PolyMet and Teck collectively own the LTV Erie plant site as part of a joint venture called “NewRange.” The plant site is comprised of buildings, power and rail infrastructure, and mine tailings basin. Previously, the plant site was part of a bankruptcy proceeding when LTV Erie closed more than 20 years ago.
Who would own the SUNDOG project?
Currently undetermined, but the site could be owned and operated by an existing electrical utility, or owned independently with power purchase agreements for the clean electricity it would produce.
How much would it cost?
At this early stage, a precise cost cannot be established. Below are a few useful points of comparison:
• A 300 MW solar array alone would cost approximately $300 million, but factors including cost of panels, cost of anchoring systems, and upgrades to connect to the power grid could increase the cost.
• The LTV Erie site is polluted and the tailings basin would need to be capped and decommissioned, which could cost over $100 million.
• Form Energy is estimating the cost per kwh of their iron-air battery system at approximately $20/kwh. Using this as an estimate, the cost of a 100 MWh battery would be around $200 million.
• The cost of acquiring the LTV Erie plant site is unknown, but the environmental liabilities of over $100 million mean that covering the cost of cleanup under state and federal programs could reduce the cost of acquiring the property.
Where would money come from?
Federal, state, IRRRB, and private sources of funding could all be part of an overall package. The recently passed Inflation Reduction Act contains several types of tax incentives that could be utilized. Previous unsuccessful proposals for mines and coal power plants in the same area have received tens of millions of dollars in aid from all levels of government. In 2016, the Minnesota Legislature approved over $80 million in construction and production incentives to build a siding plant nearby. While the plant was never built, it illustrates the capacity to aid a proposal in this area.
Can you build a solar array on top of the existing tailings basin?
Yes. The site would first need to be cleaned up—tailings basin capped, dam shored up, and polluted water captured and treated. Solar has been installed on lined solid waste landfills and reclaimed mines across the globe. While there are geotechnical challenges to overcome, there are many examples to draw on from similar installations.
Is it too far north?
No. Solar arrays have been successful in northern climates and high latitudes. In one example, Xcel Energy is planning to build a 460 MW solar array in Becker, Minnesota. Shorter winter days are counterbalanced by longer summer days, and solar panels are actually more efficient at lower temperatures.
Is there enough space?
Yes. A 300 MW solar array would require about 2,100 acres of space. The tailings basin is approximately 1,400 acres in size, and there are thousands of acres of adjacent brownfield from the defunct LTV Erie mine that would provide sufficient space for a solar array of the needed size.
Is there sufficient transmission infrastructure to move power from the site?
Recent upgrades to the line connecting the site to the defunct Taconite Harbor coal plant would allow for excess electricity to be moved on to the grid. Additional transmission upgrades may be required, depending on the installed capacity. On-site use of much of the power would limit the need for extensive off-site transmission.
How many jobs would this create?
Utility-scale solar arrays create a significant number of construction jobs. For example, a similar sized solar array in Texas projects approximately 500 skilled construction workers would be employed. Cleaning up the LTV Erie site and shoring up the tailings dam would also be a major construction project employing hundreds, as would restoring and repurposing existing buildings. The number of ongoing, permanent jobs depends on what value-added manufacturing can be attracted to the site. As an example, the EVRAZ steel mill in Pueblo, Colorado employs 1,000 workers powered by the Bighorn Solar array next to the factory. Also, this vision could protect existing employment of approximately 4,000 workers at Minnesota taconite mines by creating a value-added “clean steel” product.