Marshall County, Iowa: Power, Data Centers and the Local Economy
Home to Marshalltown and State Center
Marshall County sits inside the data center build-out. The SAVRN Data Center Map lists 1 data center in Marshall County. Marshall County is home to Marshalltown, State Center, Le Grand and Melbourne. The Moratorium Tracker holds 1 local measure here (1 in force); the latest is “Proposed county moratorium on data centers”. Unemployment was 5.5% in August 2026, against 3.9% in 2019. Its power plants have 1,190 MW of capacity, 75% of it natural gas, the 3rd largest fleet in Iowa.
Cities and towns in Marshall County
Marshall County is home to Marshalltown, State Center, Le Grand and Melbourne.
Unincorporated communities (governed by the county): Green Mountain.
Residents are 2025 Census estimates for the part of each city, town or township inside this county. Census publishes no annual estimate for unincorporated communities.
What changed in Marshall County
1st = the most. Ranks cover counties with a value on record.
| Measure | Then | Now | Change | Rank in Iowa |
|---|---|---|---|---|
| Population (2020 → 2025) | 40,100 | 39,890 | ▼ 0.5% | 15th of 99 by size |
| Total jobs (2019 → 2025) | 16,580 | 15,942 | ▼ 3.8% | 64th of 99 by growth |
| Average annual pay (2019 → 2025) | $45,942 | $58,469 | ▲ 27.3% | — |
| Construction jobs (2019 → 2025) | 519 | 508 | ▼ 2.1% | 59th of 81 by growth |
| Unemployment rate (2019 → August 2026) | 3.9% | 5.5% | ▲ 1.6pts | — |
| Generating capacity added since 2019 | — | 3 MW | — | |
| Generating capacity retired since 2019 | — | 0 MW | — |
3 MW of that came online in 2019 or later, mostly solar. Construction employs 508, down 2.1% since 2019. Employers here counted 15,942 jobs in 2025, down 3.8% from 2019. Interstate Power and Light Co is the largest utility serving Marshall County, one of 5 with territory here. Its residential customers paid an average 17.90¢/kWh in 2024, above the 13.77¢ median for Iowa utilities. 39,890 people live here, down 0.5% since 2020.
Who powers Marshall County
Net change in operating capacity since 2019: +3 MW. Colors follow the fuel legend above.
Utilities with service territory in Marshall County
| Utility | Ownership | Service | Residential customers (systemwide) | Residential price, 2024 | Commercial share of sales |
|---|---|---|---|---|---|
| Interstate Power and Light Co | Investor Owned | Bundled | 417,153 | 17.90¢ | 29% |
| Midland Power Coop | Cooperative | Bundled | 11,939 | 13.60¢ | 12% |
| Consumers Energy Coop - (IA) | Cooperative | Bundled | 6,922 | 15.00¢ | 13% |
| Grundy County Rural Elec Coop | — | — | — | — | — |
| City of State Center - (IA) | — | — | — | — | — |
Customer counts, prices and sales shares cover each utility's whole system in the state, not only this county. Commercial sales include data centers.
Operating power plants 6
| Technology | Capacity | Share |
|---|---|---|
| Natural gas | 897 MW | 75% |
| Wind | 274 MW | 23% |
| Petroleum | 15 MW | 1% |
| Solar | 3 MW | 0% |
| Battery storage | 0 MW | 0% |
| Largest plants | Owner | Technology | MW | Since |
|---|---|---|---|---|
| Marshalltown Generating Station | Interstate Power and Light Co | Natural gas | 709 MW | 2017 |
| Marshalltown | Interstate Power and Light Co | Natural gas | 189 MW | 1978 |
| Vienna Wind Farm | MidAmerican Energy Co | Wind | 150 MW | 2012 |
| Laurel Wind Farm | MidAmerican Energy Co | Wind | 123 MW | 2011 |
| Alliant SBD 9107 JBS USA | Industrial Energy Applications Inc | Petroleum | 11 MW | 1992 |
| State Center | City of State Center - (IA) | Petroleum | 7 MW | 1972 |
The Marshall County labor market
| Industry (2025) | Jobs | Average pay | Concentration vs U.S. |
|---|---|---|---|
| All industries | 15,942 | $58,469 | 1.00 |
| Construction | 508 | $73,265 | 0.60 |
| Data processing and hosting | 12 | $153,756 | 0.24 |
Concentration is the BLS location quotient: 1.0 means the industry holds the same share of local jobs as it does nationally. Industry rows count private employers; cells BLS suppresses are left out.
Data centers and local rules in Marshall County
1 data center in Marshall County is on the SAVRN Data Center Map.
Local measures 1
| Measure | Status | Date | |
|---|---|---|---|
| Proposed county moratorium on data centers | In force | 2026-09 |
Marshall County and its neighbors
Of the 6 counties that border Marshall County, Poweshiek County carries the most build-out activity: data centers, planned generation and operating plants combined.
| County | Population | Jobs since 2019 | Operating MW | Planned MW | Data centers | Local measures |
|---|---|---|---|---|---|---|
| Marshall County | 39,890 | ▼ 3.8% | 1,190 MW | — | 1 | 1 |
| Grundy County | 12,361 | ▲ 0.1% | 242 MW | — | — | — |
| Hardin County | 16,455 | ▼ 4.5% | 153 MW | — | 1 | — |
| Jasper County | 38,153 | ▼ 7.1% | — | — | — | — |
| Poweshiek County | 18,368 | ▼ 6.0% | 538 MW | — | — | — |
| Story County | 101,291 | ▲ 1.8% | 431 MW | — | — | — |
| Tama County | 16,796 | ▼ 3.2% | 180 MW | — | — | — |
More of Iowa
Marshall County, answered from the record
Who provides electricity in Marshall County, Iowa?
5 utilities have service territory in Marshall County in the EIA-861 2024 report: Interstate Power and Light Co, Midland Power Coop, Consumers Energy Coop - (IA), Grundy County Rural Elec Coop. The largest, Interstate Power and Light Co, charged residential customers 17.90¢/kWh on average in 2024.
What county is Marshalltown, IA in?
Marshalltown is in Marshall County, Iowa. About 27,536 people live there (2025 Census estimate).
What power plants are in Marshall County?
6 operating plants with 1,190 MW of capacity. The largest is Marshalltown Generating Station (709 MW, natural gas).
Are there data centers in Marshall County?
Yes. The SAVRN Data Center Map lists 1 data center in Marshall County.
Is Marshall County adding jobs?
Employers counted 15,942 jobs in 2025 against 16,580 in 2019 (-3.8%, BLS QCEW). Construction went from 519 to 508.
Does Marshall County have a data center moratorium?
The SAVRN Moratorium Tracker holds 1 local measure for Marshall County, 1 in force.