You would assume the expensive part of a solar farm is the solar. Panels, trackers, racking, the acreage underneath it all.<\/p>\n
Minnesota Power is currently building two of them at the same time, picked out of the same auction, aimed at the same completion date. Comparing the two is about as close as this industry gets to a controlled experiment, and the variable that separates them is not the panels.<\/p>\n
It is the distance to a working grid connection.<\/p>\n
Boswell Solar broke ground on July 24 in Cohasset, in Itasca County. It is 85 megawatts on about 500 acres, and to reach the grid it needs a collector substation plus a 230-kilovolt line running roughly 2.5 miles into a substation that already exists.<\/p>\n
Regal Solar, near Royalton, is 119.5 megawatts on about 800 acres. To reach the grid it needs a brand new substation and 3.5 miles of collector line built from scratch.<\/p>\n
Same utility. Same 2023 solar request for proposals. Both targeted at mid-2027. One of them inherited its plug.<\/p>\n
The reason Boswell Solar has a substation waiting for it is sitting right there on the same site, still burning coal.<\/p>\n
The Boswell Energy Center broke ground in 1956 and started commercial operation in 1958. Two units are still running: Unit 3 at 355 megawatts since 1973, and Unit 4 at 585 since 1980. Units 1 and 2 were retired back in 2018.<\/p>\n
That is 940 megawatts of coal still on the property, with 85 megawatts of solar going up beside it rather than on top of it. Coal stops at Unit 3 in 2030, when it converts to natural gas, and at Unit 4 in 2035.<\/p>\n
Seventy years of generating on that spot bought a lot of steel. Minnesota Power says the array will use the existing electric infrastructure at the site, requiring only a collector substation and a short transmission line<\/a> to tie in.<\/p>\n Xcel Energy ran the same play on a much larger scale about 90 miles south, where 710 megawatts of solar now feed the grid through the wires of the Sherco coal plant<\/a>. What makes Boswell useful is that Minnesota Power happens to be building the counterexample at the same time.<\/p>\n Royalton is farmland. There is no retiring thermal plant, no existing switchyard, no decades of transmission investment sitting in the ground waiting to be reused.<\/p>\n So Regal gets the full bill: a new substation, and 3.5 miles of collector line to reach the regional grid. It is a bigger project at 119.5 megawatts and roughly 255,000 modules across 800 acres, so some of that is simply scale.<\/p>\n But the connection work does not scale with the panels. It scales with what was already on site, which at Royalton is nothing.<\/p>\n Both projects came out of the same competitive bid round, with an independent evaluator confirming they were the most cost-competitive options for customers. State regulators granted Boswell its site permit and the route permit for the line on January 15, with the project costed at $163.5 million<\/a> in the filings, according to the Duluth News Tribune.<\/p>\n Both arrays use bifacial modules on single-axis trackers, which is why the comparison holds up. Bifacial means the panels collect light bouncing off the ground and off snow, which in northern Minnesota is less of a novelty feature than it sounds.<\/p>\n The Boswell module count depends on which document you read, incidentally. The groundbreaking release says more than 178,000. The project fact sheet counts 177,675. Chief operating officer Josh Skelton told the crowd on site it was about 180,000. Same array, rounded three ways.<\/p>\n That fact sheet also carries the numbers nobody quotes: about 167,000 megawatt-hours a year, enough for roughly 19,500 homes, and around 85 construction jobs rising to 110 at peak. Hunt Electric and Lakehead Constructors are leading the build alongside local contractors, according to remarks Skelton made at the ceremony and reported by Northern Community Radio KAXE.<\/p>\n None of this is a Minnesota invention. FERC created a formal route for it in April 2018 under Order 845, which lets a new resource take over the unused portion of an existing plant’s interconnection service instead of starting from zero.<\/p>\n It has been picking up momentum. PJM loosened its rules on the mechanism in 2025, Virginia and Indiana lawmakers passed bills in February 2026 to encourage it, and PacifiCorp has been working through dozens of requests to bolt storage and solar onto existing points of interconnection out West.<\/p>\n The pressure behind all of it is the queue. Berkeley Lab found that the median project reaching commercial operation in 2025 had spent more than five years waiting<\/a> to get there.<\/p>\n Worth one caveat on Boswell specifically. Minnesota Power has described reusing existing electric infrastructure at the site, but it has not publicly detailed which interconnection route the project took, so the mechanism is not something to assert from outside the filings. What is documented is the outcome, and the outcome is 2.5 miles against 3.5 plus a substation.<\/p>\n For what it costs when the wire is the missing piece entirely, America’s flagship wave energy test site off Oregon has been sitting wired and empty<\/a> for the opposite reason.<\/p>\n Solar is the easy half to announce. Minnesota Power’s 2025 resource plan, covering 2025 to 2039, is still in front of state regulators<\/a> in docket 25-127, and the contested part is not the panels.<\/p>\n The proposal refuels Boswell Unit 3 to run on gas by 2030, partially refuels Unit 4 for 40% gas co-firing, and adds roughly 750 megawatts of new gas by 2035 on top of those conversions. Alongside it sit 400 megawatts of wind, 100 of storage, and 100 of industrial demand response by 2028.<\/p>\n Clean-energy groups are pushing back on the gas. Fresh Energy argued in May that the utility can meet demand with wind, solar, storage and demand response using the converted Boswell units as backup, and that committing capital to new turbines this early carries avoidable cost risk.<\/p>\n There is new money behind all of it too. ALLETE, Minnesota Power’s parent, went private on December 15, 2025, bought by Canada Pension Plan Investment Board and Global Infrastructure Partners at $67 a share, with roughly $200 million in committed customer benefits including a one-year base rate freeze.<\/p>\n Minnesota Power says nearly 60% of what it delivers is already renewable, against a target of more than 80% by 2030 and a state law requiring carbon-free electricity by 2040. Boswell and Regal together account for more than two thirds of the 300 megawatts of regional solar the utility committed to.<\/p>\nRegal is what the same utility pays when nothing is there<\/h2>\n
The panels themselves are close to identical<\/h2>\n
Reusing a connection has quietly become its own line of business<\/h2>\n
The gas half of the plan is the part still being fought over<\/h2>\n
Where this leaves both sites<\/h2>\n