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Should we mine copper and nickel in Minnesota … to help defeat climate change?

It’s an argument that has become popular among supporters of the Twin Metals and PolyMet projects. Yet the clean energy case for copper-nickel mining hasn’t exactly won over skeptics in Minnesota.

PolyMet Mining hopes to build one of the state’s first copper-nickel mine.
PolyMet Mining hopes to build one of the state’s first copper-nickel mines.
MinnPost photo by Walker Orenstein

Just as steel made from Minnesota’s iron ore powered the U.S. military to victory during World War II, supporters of copper-nickel mining in the state say the industry could help defeat another global challenge: the climate crisis.

Demand is on the rise for renewable energy and electric cars that rely on copper, nickel, cobalt and other metals. And as the world continues to transition away from fossil fuels, the need for those minerals will only continue to grow. 

In August, Gov. Tim Walz told MinnPost the state should allow mining if it expects to reach a carbon-free future. “There’s 5.5 tons of copper in every megawatt of solar, and it comes from somewhere,” he said.

That argument has grown popular with Twin Metals Minnesota and PolyMet Mining, which hope to build the state’s first copper-nickel mines, as well as their political allies. It’s often used to ease concerns that a boom in so-called sulfide mining could pollute Lake Superior and the Boundary Waters Canoe Area Wilderness (BWCA) with toxic mine waste and acidic runoff.

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Yet the clean energy case has not won over ardent skeptics of copper-nickel mining in the state. Environmental groups say a focus on recycling and mining in more favorable environments can ensure an energy transition without risk of water pollution in Minnesota. Some have accused mining companies of being insincere to say they’re helping fight climate change when they have not advocated for clean energy policy at the Legislature.

“Actions speak louder than words for these mining companies,” said Kathryn Hoffman, CEO of the Minnesota Center for Environmental Advocacy. “We need policy change to move us toward a clean energy economy.”

Will a green boom need an influx of metals?

The statistic Walz cited — that there’s 5.5 tons of copper used to produce every megawatt of solar power — is frequently promoted by the Copper Development Association (CDA), an industry marketing group. The organization also says there’s up to 4.7 tons of copper in every three megawatt wind turbine, plus a need for the metals in batteries that store clean energy and power electric vehicles.

The metal is so popular because it can conduct heat and electricity well and is easily bent into wires or sheets. The CDA says without copper, electrical equipment like motors and cables would use 20 percent more materials. Copper can also be recycled time and again.

Nickel, the other primary mineral Twin Metals and PolyMet would mine, is a crucial component of many batteries used by electric cars. The same is true for cobalt, which is needed in lithium-ion batteries and would be mined. (Steel is also critical to wind turbines.)

Demand for renewable energy and electric vehicles is growing. Wind and solar could soon be cheaper than coal and gas across the United States, and electric vehicles continue to sell at higher rates globally.

Nickel, the other primary mineral Twin Metals and PolyMet would mine, is a crucial component of many batteries used by electric cars.
In Minnesota, Xcel Energy’s path to carbon-free energy by 2050 includes massive expansion of renewables. By 2030, the company hopes to add 3,000 megawatts of solar power, enough for more than 650,000 homes, and launch the biggest wind expansion in its history by 2022.

A 2017 World Bank report says if the world builds enough wind technology to keep global warming to a 2 degree increase — a benchmark in the Paris Climate agreement — there could be a roughly 250 percent hike in industry demand for copper and nickel through 2050. For solar, it could be about a 300 percent increase. For energy storage technology, the need for nickel could rise nearly 1,200 percent.

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That doesn’t mean the United States can feed the world’s appetite for metals on its own. The country trailed Chile, China and Peru in 2018 copper output. The U.S. has less in reserves than even Australia and Mexico, according to the U.S. Geological Survey. It’s an even smaller part of the nickel industry, producing less in 2018 at least a dozen countries, including Canada, China and Australia. Its reserves pale in comparison to those countries, as well.

Still, Minnesota has a lot to contribute. The sites that Twin Metals and PolyMet hope to mine are within the untapped Duluth Complex, which holds the world’s second largest copper deposit and its third largest nickel deposit.

Bruce Richardson, a spokesman for PolyMet, said the company doesn’t know how much metal produced at their mine would eventually be used for renewable energy and other environmentally friendly technology. A commodity sold in a world market “could end up anywhere,” he said in an email.

Nickel production and reserves for selected countries in metric tons
Country2018 productionReserves
New Caledonia210,000N/A
United States19,000110,000
Source: U.S. Geological Survey
Copper production and reserves for selected countries in thousand metric tons
Country2018 productionReserves
United States1,20048,000
Source: U.S. Geological Survey

But Richardson said the company’s focus “remains on bringing on new production responsibly” to meet the mineral demand. “The metals for green technologies have to come from somewhere … so why not from Minnesota?” he said.

Kathy Graul, a spokeswoman for Twin Metals, said “if we don’t mine the metals that are needed to meet the demand and advance the green economy, we simply can’t make the transition to carbon-free technologies.”

Reduce, reuse, recycle

Many opponents of copper-nickel mining say the need for metals that create green technology is not justification enough to risk water pollution from PolyMet and Twin Metals.

Sulfide mining carries risks to water that iron ore mining does not. When the ore-bearing rock is exposed to air and water, it can create an acidic runoff and leach heavy metals into waterways. Such pollution has plagued the industry, although Twin Metals and PolyMet maintain they can meet state environmental standards with modern mining technology such as intensive water treatment.

PolyMet’s project, owned by Swiss mining behemoth Glencore, has all permits to begin construction and is working to finance its $1 billion open-pit mine near Hoyt Lakes. The project would sit in the watershed of the St. Louis River and Lake Superior. Twin Metals, owned by Chile’s Antofagasta, would be in the watershed of the Rainy River and the BWCA. The company expects to submit a plan for its underground mine near Ely to regulators this year.

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State Rep. Kelly Morrison, a DFLer from Deephaven, said she is concerned the state’s environmental laws aren’t tough enough and worried the state’s financial assurance package with PolyMet will leave taxpayers, not Glencore, on the hook for cleanup. 

Morrison said the world is “vastly underutilizing recycling of these metals” and should always be looking for ways to build a carbon-free economy that involves little to no mining. A United Nations report from 2013 says more than 50 percent of “end-of-life” copper, nickel, cobalt and palladium is recycled, but that metal recycling could be improved. The World Bank research on future metal needs does not factor in recycling.

Still, Morrison said recycling isn’t likely to cover all the demand for metal, and the U.N. report says there are significant barriers to higher recycling rates. But Morrison said mining in drier places should still be the priority. Most hard rock mining in the country takes place in the West. Many of the world’s largest copper mines are in deserts, like Chile’s Atacama. (Although those mines have drawn environmental concerns, too.)

Glencore's corporate offices in Switzerland
Courtesy of Glencore
PolyMet’s project, owned by Swiss mining behemoth Glencore, has all permits to begin construction and is working to finance its $1 billion open-pit mine near Hoyt Lakes.
“I would just hope that we would do it in the safest possible way when you look at people, water, and the economy,” Morrison said. “And I would make the case that is not what we currently have set up in the case of PolyMet or Twin Metals.”

Hoffman, of the MCEA, said PolyMet and Twin Metals would be “barely a bug on the windshield of the global copper market” if built. An increase of a capacity at existing mines could “dwarf the effects of PolyMet,” she said.

No green-mining harmony in state politics

If mining supporters and clean energy advocates have a shared interest in advancing renewable energy, they have not forged an alliance in Minnesota.

Prominent renewable power groups Fresh Energy and the Center for Energy and Environment declined to comment for this article. An Xcel Energy spokesman did not respond to a request for comment.

Peder Mewis, a regional policy manager for the nonprofit Clean Grid Alliance, told MinnPost the Iron Mining Association  — a supporter of copper-nickel mining — has been an influential roadblock to policy at the Legislature that aims to speed up the transition from fossil fuels to carbon-free energy. Twin Metals and PolyMet have stayed away from the debate. That has irked some as hypocritical, or a missed opportunity for a strong political partnership.

Gov. Tim Walz
Gov. Tim Walz
The main priority of many DFLers and some Republicans is “clean energy first,” a regulation that would make it tougher for the Public Utilities Commission to approve new fossil fuel power projects. Walz’s proposal for a carbon-free energy grid by 2050 is another agenda-topper for many environmental groups and Democrats.

Mewis said he has worked to convince mining advocates that “clean energy first” could boost wind energy and increase the need for steel. Separately, the North Dakota and Minnesota chapter of the Laborer’s International Union of North America has promoted the legislation as a potential boon for the copper and iron ore mining industries.

Richardson, the PolyMet spokesman, said his company is “neutral” on the clean energy regulation and Walz’s carbon-free energy plan. Twin Metals declined to comment on either piece of legislation and said the market is already moving toward a greener economy.

Nancy Norr, chairwoman of Jobs for Minnesotans, a coalition of construction unions, Minnesota Power and pro-business organizations like the Chamber of Commerce, said her group “stands in alignment with Governor Walz” on the need for copper, nickel iron and more to support a greener economy. But the organization is also neutral on the bills at the Legislature.

Kelsey Johnson, president of the Iron Mining Association, told MinnPost that power rates have jumped 60 percent since 2007 for her energy-intensive industry, which is supplied by  the northern utility Minnesota Power. She said big utilities like Xcel Energy are already moving to clean energy by 2050 without stricter government mandates, and new regulations could impose higher prices on smaller power companies and their customers. 

Minnesota Power said it’s on track to provide 50 percent renewable energy by 2021, but Bethany Owen, president of its parent company ALLETE, said the company is “mindful of the impacts the pace of change has on our customers and communities.” They didn’t comment on the legislation at the Capitol.

Plus, Johnson said Minnesota’s iron ore mines generally don’t supply steel for wind turbines. The state’s iron ore is commonly used as steel for construction materials and household appliances. “As we continue to move forward toward a more green economy, we have to take into consideration industries like American iron and steel and our cost competitiveness as we compete on a global market,” Johnson said.

State Rep. Jamie Long
State Rep. Jamie Long
In response, Hoffman said mining companies that are sincere about fighting climate change should lobby with the MCEA for Walz’s carbon-free 2050 plan. She noted Glencore, PolyMet’s majority owner, has a massive portfolio of 26 coal mines.  

Rep. Jamie Long, a Minneapolis DFLer who is a top House negotiator on “clean energy first” and Walz’s carbon-free plan, recently told a crowd of SEIU union members that it’s a “false choice” to say Minnesota needs to mine for copper to beat global warming.

On the forefront of this divide is the BlueGreen Alliance, which includes pro-mining labor unions like the United Steelworkers and more skeptical environmental groups like the Sierra Club. Mike Williams, the BGA’s national deputy director, said they don’t have a position on PolyMet or Twin Metals, though he said Twin Metals has “substantially higher” environmental concerns.

“It’s an incredibly critical topic,” Williams said. “One, it’s contentious and it’s contentious for a reason — mining is a very intrusive and sometimes very polluting process. Two, we can’t have a modern society without these minerals and materials. And three, it does provide good jobs.”

This post has been updated to clarify Peder Mewis’ views on Minnesota Power’s role in the politics of clean energy at the Capitol.