IA — Power Infrastructure Updated 2026-07-17

Iowa

MISO Nuclear Solar Wind Storage Data Center PPAs Transmission Constraints

1. Grid operator and market structure

  • Balancing authority / RTO: Iowa utilities including MidAmerican Energy and Interstate Power and Light/Alliant Energy operate in the Midcontinent Independent System Operator (MISO) footprint, so regional generation interconnection, transmission expansion, and resource-adequacy constraints are principally MISO issues MISO, 2026-06-10.
  • Retail market structure: Iowa remains a traditionally regulated retail electricity state rather than a retail-choice state; EIA’s Iowa electricity profile reports full-service-provider sales and no meaningful energy-only provider sales U.S. Energy Information Administration, 2025-11-04.

2. Interconnection queue status (MISO)

  • Queue scale changed materially by March 2026: MISO’s March 24, 2026 generator-interconnection queue update reported 192 GW in the active queue as of March 6, 2026, down 38% from 308 GW one year earlier, while also identifying 76 GW of approved generation projects not yet constructed MISO, 2026-03-24.
  • Queue timing: MISO reported that there was no 2024 interconnection cycle, that the 2023 cycle began processing in Q4 2025, and that the 2025 cycle began in Q1 2026 MISO, 2026-03-24.
  • Large-load workstream: MISO’s January 30, 2026 Large Load Additions Workshop stated that the system is seeing an “unprecedented surge” in large-load interconnection requests primarily from data centers, and that MISO is developing reliability requirements around ramping, telemetry, load modeling, and transmission studies MISO, 2026-01-30.
  • Near-term regional forecast: MISO’s April long-term-load-forecast summary identified an expected 8-14 GW of data-center growth in 2026-2027 as a key near-term indicator and said public large-load announcements and expedited-project-review activity were increasing forecast uncertainty MISO, 2026-04-13.
  • FERC opened a MISO large-load proceeding: On June 18, FERC instituted Federal Power Act section 206 docket EL26-70-000, preliminarily finding that MISO’s tariff may be unjust and unreasonable because it lacks a consistent, transparent process for large and co-located loads. The order requires MISO to address transmission-service eligibility, cost-shift protections and cost-recovery agreements, behind-the-meter/co-location rules, flexible load, generation serving electrically proximate load, and an informational-reporting framework; it is a regional rulemaking proceeding, not a final Iowa tariff FERC, 2026-06-18.
  • Iowa-specific queue visibility: MISO’s public generation queue and 2026 queue update still do not identify Iowa data centers as a distinct load category, so Iowa data-center impacts are more visible in utility load forecasts, individual customer-rate filings, and local interconnection/resource-planning materials than in MISO queue labels MISO, 2026-03-24 MISO, 2026-01-30.

3. Ratepayer protection (large-load tariffs / cost allocation)

  • Alliant individual-customer rates: Alliant’s February 19, 2026 earnings materials list Iowa Utilities Commission docket TF-2025-0007 for a Google individual customer rate and TF-2025-0047 for a QTS-Cedar Rapids individual customer rate; EEI’s May 2026 large-customer tariff survey likewise states that IPL/Alliant’s ICR service agreement for Vulpine Power/Google was approved and that a second ICR service agreement for QTS was approved Alliant Energy, 2026-02-19 Edison Electric Institute, 2026-05-08.
  • Alliant load growth and rate freeze: Alliant’s Q4 2025 earnings slides say 3 GW of data-center demand is driving a 50% projected demand increase by 2031 from 2025 levels, while Alliant’s April 30, 2026 Q1 release says a new approximately 370 MW Iowa data-center electric service agreement raised total contracted data-center demand to approximately 3.4 GW; EEI’s May 2026 survey says Alliant has implemented a five-year Iowa base electric rate freeze supported by data-center growth Alliant Energy, 2026-02-19 Alliant Energy, 2026-04-30 Edison Electric Institute, 2026-05-08.
  • Alliant ICR pipeline: Alliant’s May 2026 investor slides identify a QTS 2 data center in Iowa and a separate 370 MW data center in Iowa, and list the expected filing of QTS 2 and 370 MW Iowa individual-customer-rate data-center contracts as items to watch Alliant Energy AGA slides, 2026-05-17.
  • No enacted statewide data-center tariff class: HF 2690 would have required a separate Iowa Utilities Commission data-center service classification and tariff schedule that directly assigned or proportionally allocated data-center service costs and mitigated cost-shifting to other retail classes. It was introduced February 23, drew six filed amendments on March 11-12, never received a House floor vote, and died on the calendar Iowa Legislature, HF 2690 bill text, 2026-02-23 Iowa Legislature bill history, HF 2690, 2026-07-16.
  • MidAmerican contract posture: MidAmerican states that its data-center and large-user agreements require customer-specific commitments, including paying for power for 10 years and early-exit penalties, to protect other customers from cost shifts MidAmerican Energy, 2026-06-10.
  • Local public-power cost allocation: Ames staff estimated that LightEdge’s proposed facility would begin at roughly 3 MW and could reach 25 MW over ten years; existing infrastructure could serve the first phase, while later phases could require a dedicated feeder and substation. The proposal stated that LightEdge would pay project-specific electric infrastructure costs, and the council delayed action July 14 while it develops broader data-center rules City of Ames staff report, 2026-06-23 KCCI, 2026-07-15.

4. Generation adequacy (new supply, storage, and shortfall concerns)

  • MidAmerican resource plan: MidAmerican’s 2024 Resource Evaluation Study split load between historical load and new data-center load and modeled the hourly profile of post-2021 data-center load; the study projected about 2.3% annual Iowa/South Dakota retail load growth for the next five years and 1.9% compound annual growth over the 20-year horizon MidAmerican Energy, 2024-11-01.
  • MidAmerican supply additions: MidAmerican’s public RES release describes an “all-of-the-above” plan to meet significant projected demand growth, and the RES preferred near-term portfolio included new solar and natural-gas combustion-turbine capacity to address load and capacity needs MidAmerican Energy, 2024-11-01 MidAmerican Energy, 2024-11-01.
  • Alliant supply pressure: Alliant’s 2026 investor materials identify data-center construction and commissioning sales in retail-sales growth and list new generation and customer-rate proceedings alongside Google and QTS ICR dockets Alliant Energy, 2026-02-19.
  • Alliant wind advance-ratemaking order: On March 11, 2026, the Iowa Utilities Commission approved advance ratemaking principles for IPL/Alliant’s proposed up to 1,000 MW of new wind generation in docket RPU-2025-0003; the order noted that IPL’s resource evaluation study identified a five-year action-plan need for 1,000 MW of wind, 500 MW of battery storage, 845 MW of natural-gas peaking, and 430 MW of combined-cycle capacity, with load-growth forecasting contested by intervenors Iowa Utilities Commission order, 2026-03-11.
  • Cedar River Generating Station permit: Iowa DNR issued air-construction permits on February 2 for IPL/Alliant’s new Cedar River Generating Station at the Prairie Creek site, including five approximately 18.8 MW natural-gas reciprocating engines (about 94 MW total) and an emergency diesel generator Iowa Department of Natural Resources, 2026-02-02.
  • Morgan Valley Energy Center: Alliant filed an Iowa Utilities Commission generating-certificate application in docket GCU-2026-0002 and, on July 15, a Linn County request to rezone approximately 160 acres for three natural-gas combustion turbines totaling about 720 MW, with operation targeted for 2030. Alliant says the plant addresses overall load growth, reliability, and regional capacity—not a single named data center—but it would be located near the state’s largest disclosed data-center load growth Linn County, 2026-07-16 Alliant Energy, 2026-07-16.
  • Duane Arnold restart: NextEra announced a restart plan for the 615 MW Duane Arnold Energy Center before the end of 2029, and Iowa reporting says Google is expected to take roughly 565 MW under a long-term power agreement, making the restart the most visible generation-supply development tied to Iowa data-center load in the February-July 2026 update window NextEra Energy, 2025-10-27 Iowa Public Radio, 2026-04-29.
  • Nuclear tax law: HF 2757, signed June 1, 2026, created a sales/use tax exemption for nuclear electric generation facilities and a nuclear workforce fund contribution of $2,200 per MW of approved nameplate capacity; the final fiscal note assumes a $1.6 billion Duane Arnold restart project and 615 MW of nameplate capacity Iowa Legislature, HF 2757 enrolled bill, 2026-06-01 Iowa Legislative Services Agency fiscal note, 2026-05-20.

5. Utility load forecasts (data-center driven growth)

  • New statutory forecast process: HF 2799 requires the Iowa Economic Development Authority to commission Iowa State University at least every two years to produce a public report forecasting future electricity use in Iowa and the Midwest and analyzing electric-transmission-system expansion plans; the first load forecast and transmission analysis must be published by December 31, 2028 Iowa Legislature, HF 2799 enrolled bill, 2026-06-02.
  • Utility data for the forecast: HF 2799 gives the Iowa Utilities Commission authority to compel public utilities to share information needed for the Iowa State load forecast and transmission analysis, subject to confidentiality protections, and allows the aggregate analysis to be used as evidence in commission proceedings Iowa Legislature, HF 2799 enrolled bill, 2026-06-02.
  • Forecast funding: HF 2799 creates an electric-transmission-system expansion planning and load-forecasting fund supported by electric-utility remittances of up to 0.02% of prior-year intrastate gross operating revenues Iowa Legislature, HF 2799 enrolled bill, 2026-06-02.
  • Current utility signals: As of July 17, 2026, the strongest public Iowa data-center load signals are Alliant’s approximately 3.4 GW of contracted data-center demand, MISO’s regional 8-14 GW near-term data-center-growth indicator, and MidAmerican’s RES data-center load split—not a state-published all-utility load forecast, which will not exist under HF 2799 until 2028 Alliant Energy, 2026-04-30 MISO, 2026-04-13 MidAmerican Energy, 2024-11-01 Iowa Legislature, HF 2799 enrolled bill, 2026-06-02.
  • New central-Iowa agreements do not yet equal firm load: Van Meter’s March 23 Microsoft development agreement covers one or more data centers and makes Microsoft responsible for city infrastructure costs, but does not state MW or a construction schedule. Norwalk’s March 5 Project West agreement enabled infrastructure and site preparation for a reported $12 billion campus, while the city still lacked an identified end user in late June; neither local agreement is evidence of a completed utility interconnection City of Van Meter, 2026-04-13 KCCI, 2026-03-06 KNIA/KRLS, 2026-06-29.
  • Published project MW estimates: MISO’s December 2024 informational list associated Microsoft Van Meter with 415 MW and Google Cedar Rapids with 600 MW; TAI’s March 2026 Cleanview-derived inventory estimates QTS Cedar Rapids at 616 MW, Microsoft Ginger East at 444 MW, Ginger West at 207 MW, Ruthenium at 113 MW, and Edged Des Moines at 13 MW. These estimates provide scale but are not substitutes for executed service agreements, ICRs, or completed interconnection studies MISO, 2024-12-06 Economic Impact Study of Data Centers in Iowa, 2026-03-12.
  • Industry-study electricity context: The Technology Association of Iowa’s March 2026 economic impact study reported that Iowa electricity sales increased 70% from 2010 to 2025, while Iowa’s average 2025 electricity price was 10.02 cents/kWh compared with a national average of 14.51 cents/kWh Technology Association of Iowa, 2026-03-12.

6. Behind-the-meter (BTM) / co-location / direct PPAs

  • Duane Arnold is a direct-supply development, not an Iowa BTM tariff order: NextEra and Google announced a long-term agreement tied to restarting Duane Arnold, but the public record reviewed for this update did not identify an Iowa Utilities Commission order approving a behind-the-meter data-center co-location tariff for the project NextEra Energy, 2025-10-27 Iowa Public Radio, 2026-04-29.
  • MISO regional context: MISO’s January 2026 large-load workshop discussed co-located generation/load and zero-injection generation interconnection agreements as potential tools for fast large-load service, but treated them as regional process options rather than Iowa-specific approved arrangements MISO, 2026-01-30.
  • FERC review now controls the next regional step: Docket EL26-70-000 specifically asks MISO to justify or reform its treatment of co-located and behind-the-meter generation serving large loads, including jurisdiction, definitions, transmission-service obligations, interconnection procedures, and protections against cost shifts. No final MISO compliance tariff had been approved by July 17 FERC, 2026-06-18.

7. Transmission constraints and upgrades

  • MISO transmission planning pressure: MISO’s January 2026 large-load materials describe Expedited Project Review for large loads, transmission planning, and new requirements needed to handle data-center-driven load additions; the same materials identify load forecast uncertainty and operating-timeframe forecasting for non-conforming large loads as reliability issues MISO, 2026-01-30.
  • JTIQ and ERAS: MISO’s March 2026 queue update says the Expedited Resource Addition Study process had 53 active applications totaling 27 GW and that the MISO/SPP Joint Targeted Interconnection Queue process had enabled 13 GW of generation with another 15 GW under study MISO, 2026-03-24.
  • State-level transmission analysis: HF 2799 makes load forecasting and transmission-expansion analysis a recurring state economic-development tool, which is a direct response to the scale of large-load growth even though the statute is not limited to data centers Iowa Legislature, HF 2799 enrolled bill, 2026-06-02.
  • Northwest Iowa site-cost commitment: MidAmerican said a future customer at the approximately 900-acre Salix site would be responsible for the full cost of generation, transmission, substations, and related infrastructure; no customer, MW amount, or interconnection agreement was public by the cutoff Iowa Public Radio, 2026-06-17.

Notes on data center impacts

  • Iowa’s most concrete data-center energy signals as of July 17, 2026 are (1) Alliant’s approved Google and QTS individual-customer-rate agreements, (2) Alliant’s approximately 3.4 GW contracted data-center demand and expected QTS 2 / 370 MW ICR filings, (3) MidAmerican’s customer-commitment model and RES load modeling, (4) HF 2799’s future state load forecast, (5) the Duane Arnold restart linked to Google, (6) new Alliant generation proposals totaling roughly 814 MW at Cedar River and Morgan Valley, and (7) FERC’s open MISO large-load proceeding. The public record still did not show a completed QTS 2 or 370 MW Iowa ICR filing, a statewide data-center tariff, or a final MISO large-load tariff Alliant Energy, 2026-04-30 Alliant Energy AGA slides, 2026-05-17 Alliant Energy, 2026-07-16 FERC, 2026-06-18.