Capital Program Planning for Montana Electric Utilities

by | Oct 21, 2026

Montana · Electric & Grid Utilities

Montana is doubling down on coal and gas while the West bets on transmission. Your capital plan is where those bets get paid for.

NorthWestern Energy just became Colstrip's majority owner, brought a new gas plant online under a cloud of litigation, and is fielding data-center inquiries the grid has never seen — all while a $6 billion line prepares to tie Montana into two grids at once. Each of those moves reshuffles the projects on your list. Invizion helps electric utilities re-sequence a capital portfolio in a click — and defend every decision.

See how Invizion helps utilities See what Montana utilities face Download the briefing (PDF)
The bottom line: Montana is doubling down on coal and gas — a 55% Colstrip stake and a new Laurel gas plant — just as data centers arrive and a $6 billion line prepares to tie the state into two grids. The utilities that stay ahead will be the ones whose capital plans can re-sequence as fast as those bets change.
11+1
Companies that had sought NorthWestern power for Montana data centers as of early 2026, on top of three signed deals.
20282
Year WECC warns the West could begin facing energy shortfalls, with the Basin and Northwest most exposed.
55%3
NorthWestern's majority stake in Colstrip after acquiring 592 MW from two exiting Washington utilities for $0.
$700M4
Federal DOE grant to advance the North Plains Connector, the first line bridging the eastern and western grids.

The Montana Landscape

Four forces are moving your project list at once

None of these is theoretical, and none of them waits for your next budget cycle. Together they mean the capital plan you approved last year may already be the wrong plan.

Demand — Load Growth

Data centers arrive in a slow-growth grid

NorthWestern has signed agreements with at least three data centers in 18 months, and by early 2026 at least 11 companies had sought access to its power — each capable of consuming as much energy as a small city.1

For a utility serving roughly 413,000 Montana electric customers, a single large load is a capacity commitment that competes with everything else on the list — which is why cost-allocation and a large-load tariff are now live questions at the Commission.1

Reliability — Resource Adequacy

Thin margins across the West

WECC's 2025 assessment warns the West could see energy shortfalls as early as 2028, with the Basin and Northwest subregions most exposed and roughly 80% of their planned additions still classed as speculative.2

Montana's own plan is contested: the PSC voted 3–1 to reject NorthWestern's 2026 resource plan after an independent review found it failed to justify expensive new generation.5

Generation — The Transition

Doubling down on coal and gas

While neighboring states exit coal, NorthWestern became Colstrip's majority owner in January 2026, taking 592 MW from Avista and Puget Sound Energy for $0 as Washington's climate law forced them out.3 A federal repeal of the MATS rule spared the plant a roughly $350 million upgrade decision.7

Alongside coal, the utility brought its 175 MW Yellowstone County (Laurel) gas plant online in late 2024 — after a district court vacated its air-quality permit in 2023 and the Montana Supreme Court reinstated it while ordering a greenhouse-gas study.6

Capital — Transmission & Grid

A $6 billion line and a growing rate base

The North Plains Connector — a 420-mile, up-to-525 kV, 3,000 MW HVDC line from Colstrip to North Dakota — would be the first major tie between the eastern and western grids, an estimated $6 billion investment led by Grid United and ALLETE.8

On the distribution side, NorthWestern's 2024 rate filing sought about $193 million in additional annual revenue at a 10.8% requested ROE, driven by the gas plant, poles, and pipelines.9 New obligations don't replace the backlog — they stack on it.

Who Runs Montana's Grid

One dominant investor-owned utility, a merchant coal fleet, and a deep cooperative bench

Montana's grid is carried by NorthWestern Energy, a smaller investor-owned utility in the east, the merchant-owned Colstrip complex, and more than two dozen rural cooperatives and tribal power entities. The pressures are shared; the accountability path differs.

Investor-owned & merchant

Retail rates regulated by the Montana PSC

NorthWestern Energy ~413,000 Montana electric customers · 850,300 total across MT/SD/NE110
Montana-Dakota Utilities (MDU) Electric & gas across eastern Montana
Talen Energy — Colstrip Merchant operator of Colstrip Units 3–43

NorthWestern now holds a 55% majority stake in Colstrip after acquiring 592 MW for $0 from two exiting Washington utilities.3

Cooperatives, public power & tribal

Governed by boards & members, not PSC rates

Montana's rural electric cooperatives More than two dozen distribution coops statewide
Basin Electric Power Cooperative G&T; 138 member systems across nine states incl. MT11
Big Horn County Electric Cooperative Took part of a 58 MW Colstrip block12
Energy Keepers, Inc. (CSKT) Tribally owned; operates the former Kerr Dam12

Flathead Electric Cooperative is Montana's largest distribution cooperative; most coops buy wholesale power and share the same supply and reliability pressures.

Rate-Setting & Oversight

Every capital dollar has to be defensible

Whether you answer to the Public Service Commission or a member board, the question is the same: why this project, why now, why at this cost?

  • Montana Public Service Commission (PSC) — five commissioners elected to four-year terms from five districts regulate NorthWestern's and MDU's rates, capital recovery, and resource plans.13
  • 2023 rate case: in October 2023 the PSC approved an $82 million electricity increase for NorthWestern's roughly 406,000 customers — about $25 a month for a typical home, and hotly contested.9
  • 2024–25 rate case: NorthWestern sought about $193 million in added annual revenue at a 10.8% requested ROE, then implemented a 17% electricity increase in May 2025 without approval after the nine-month statutory window lapsed.914
  • Integrated Resource Plan: the PSC rejected NorthWestern's 2026 IRP 3–1 after an independent review found it did not justify new generation and barely addressed climate — approvals are not a formality.5

Funding On The Table

The money is moving — can your plan absorb it?

Montana utilities have more grid capital in play than in a generation, and much of it is transmission-scale. The constraint is readiness: which projects qualify, which are shovel-ready, and how the timing lines up.

  • DOE grant: $700M for the North Plains Connector (2024) — to advance the nation's first transmission tie between the eastern and western grids, anchored at Colstrip.4
  • North Plains Connector: ~$6B total — a 3,000 MW, 420-mile HVDC line led by Grid United and ALLETE, targeting operation around 2032.8
  • DOE GRIP: a $10.5B national program under the Bipartisan Infrastructure Law is still deploying grid-resilience and transmission dollars utilities can compete for.15
  • Colstrip's zero-dollar catch: the 592 MW cost $0 to acquire, but NorthWestern expects about $18 million a year in O&M just for the added shares — ongoing capital, not a one-time buy.12
  • IRA elective-pay (direct-pay) credits let cooperatives and tribal utilities like Basin Electric and Energy Keepers monetize clean-energy tax credits they once couldn't use.

Where Invizion Fits

Turn Montana's grid build-out into a defensible capital plan

Invizion is scenario-based capital portfolio optimization built for utilities. When load forecasts jump, a grant lands, or a retirement date moves, you don't re-plan by hand for weeks — you model it and decide with a record to stand behind.

1

Model the “what-if” before it's forced on you

A data-center interconnect, a delayed transmission line, a moved retirement date — build the scenario and see the impact on the whole portfolio, side by side with today's plan.

2

Re-sequence 500 projects in a click

When priorities move, Invizion re-orders the portfolio automatically — accelerating, stretching, or deferring projects against the constraints you set, not weeks of spreadsheet surgery.

3

Give regulators or your board a defensible record

Every prioritization and trade-off is captured. When you're asked “why this project, why now,” the answer is documented — not reconstructed after the fact.

Montana's Grid, In Brief

Questions Montana utility leaders are asking

Short, sourced answers — the same facts we dig into with utilities looking at their capital programs.

Is electricity demand really growing in Montana?
Historically Montana has been a slow-growth, coal-heavy grid — it generated about 26.9 million MWh in 2024 with coal as its primary source.16 The new pressure is data centers: NorthWestern signed at least three deals in 18 months, and by early 2026 at least 11 companies had sought its power.1
What's happening with Colstrip?
As Washington's climate law forced Avista and Puget Sound Energy out at the end of 2025, NorthWestern took their 592 MW for $0 and became the 55% majority owner of Montana's largest power plant in January 2026; a federal MATS repeal then spared it a roughly $350 million upgrade decision.37
What is the North Plains Connector?
It's a proposed 3,000 MW, 420-mile HVDC line from Colstrip to North Dakota — the first major tie between the eastern and western grids — an estimated $6 billion project that landed a $700 million federal DOE grant in 2024.48
Does the Public Service Commission set my rates?
The PSC — five elected commissioners — regulates rates and resource plans for investor-owned utilities like NorthWestern and MDU. Cooperatives and tribal utilities set their own rates through member boards.13
What grid funding is available in Montana?
The North Plains Connector won a $700 million DOE grant, and the $10.5 billion federal GRIP program is still awarding grid-resilience and transmission dollars utilities can compete for.415
How does Invizion help Montana electric utilities plan capital?
Invizion is scenario-based capital portfolio optimization for utilities. It lets you model how a data-center load, a Colstrip cost, a grant, or a transmission decision reshuffles your whole project list, re-sequence the portfolio automatically, and keep a defensible record of every decision for the PSC or your board.

Go Deeper

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About the Author

GB

Guy Barlow

President, Invizion

Guy Barlow leads Invizion, a capital lifecycle management platform for water and wastewater utilities. He has spent two decades at the intersection of utility capital programs, funding, and analytics, helping utilities make faster, more defensible capital decisions.

Explore Further

See how utilities keep capital plans defensible

Invizion helps utilities model, optimize, and defend their capital programs. Explore how it works, or read our latest thinking on capital planning across the utility sector.

Explore Invizion

This briefing was last reviewed September 2026.

Sources

  1. Montana Free Press — NorthWestern data-center agreements and ~413,000 customers, 2026. montanafreepress.org
  2. WECC 2025 Western Assessment of Resource Adequacy — possible Western shortfalls by 2028; Basin/Northwest additions ~80% speculative. feature.wecc.org
  3. Montana Free Press — NorthWestern now owns 592 extra MW / 55% of Colstrip, acquired for $0, 2026. montanafreepress.org
  4. Montana Free Press — Montana lands $700 million for the North Plains Connector, 2024. montanafreepress.org
  5. Montana Free Press — PSC rejects NorthWestern's 2026 IRP 3–1 after independent review; costs up ~40% since 2022, 2026. montanafreepress.org
  6. Montana Free Press — Montana Supreme Court reinstates 175 MW Yellowstone County (Laurel) gas plant permit, orders GHG study; permit vacated 2023, 2025. montanafreepress.org
  7. Montana Free Press — EPA repeal of MATS rule spares Colstrip a ~$350M upgrade; Montana's largest generator, 2026. montanafreepress.org
  8. North Plains Connector — 420-mile, up-to-525 kV, 3,000 MW HVDC line, Colstrip MT to North Dakota, ~$6B, Grid United & ALLETE. northplainsconnector.com
  9. Montana Free Press — NorthWestern rate hike request ~$193M, 10.8% ROE, 175 MW $310–320M gas plant; Oct 2023 $82M increase for 406,000 customers, 2024. montanafreepress.org
  10. NorthWestern Energy — About Us: 850,300 customers across Montana, South Dakota, and Nebraska. northwesternenergy.com
  11. Basin Electric Power Cooperative — generation & transmission cooperative owned by 138 member systems across nine states. basinelectric.com
  12. Montana Free Press — Colstrip a significant obligation: ~$18M/yr O&M for added shares; 58 MW to Big Horn County Electric and Energy Keepers, 2025. montanafreepress.org
  13. Montana Public Service Commission — five commissioners elected to four-year terms from five districts. psc.mt.gov
  14. Montana Free Press — NorthWestern implements 17% electricity rate increase without PSC approval after nine-month window, 2025. montanafreepress.org
  15. U.S. Department of Energy, Grid Deployment Office — $10.5 billion Grid Resilience and Innovation Partnerships (GRIP) Program. energy.gov
  16. U.S. Energy Information Administration — Montana Electricity Profile: ~26.9 million MWh net generation (2024), 10.83 cents/kWh, coal primary source. eia.gov