Putnam County, Illinois: Power, Data Centers and the Local Economy
Home to Granville Township, Granville and Hennepin Township
The power plants that defined Putnam County are changing. Putnam County is home to Granville Township, Granville, Hennepin Township and Magnolia Township. Next door, LaSalle County has 322 MW of planned generation. 306 MW has retired here since 2019, including Hennepin Power Station (coal, 306 MW, 2019). Unemployment was 3.9% in August 2026, against 4.9% in 2019. Employers here counted 2,002 jobs in 2025, up 6.7% from 2019.
Cities and towns in Putnam County
Putnam County is home to Granville Township, Granville, Hennepin Township and Magnolia Township.
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 Putnam County
1st = the most. Ranks cover counties with a value on record.
| Measure | Then | Now | Change | Rank in Illinois |
|---|---|---|---|---|
| Population (2020 → 2025) | 5,624 | 5,619 | ▼ 0.1% | 94th of 102 by size |
| Total jobs (2019 → 2025) | 1,877 | 2,002 | ▲ 6.7% | 15th of 102 by growth |
| Average annual pay (2019 → 2025) | $49,572 | $73,073 | ▲ 47.4% | — |
| Unemployment rate (2019 → August 2026) | 4.9% | 3.9% | ▼ 1.0pts | — |
| Generating capacity added since 2019 | — | 4 MW | — | |
| Generating capacity retired since 2019 | — | 306 MW | — |
4 MW of that came online in 2019 or later, mostly solar. Its power plants have 4 MW of capacity, 100% of it solar. Ameren Illinois Company is the largest utility serving Putnam County, one of 2 with territory here. Its residential customers paid an average 15.26¢/kWh in 2024. 5,619 people live here, down 0.1% since 2020.
Who powers Putnam County
Net change in operating capacity since 2019: −302 MW. Colors follow the fuel legend above.
Utilities with service territory in Putnam County
| Utility | Ownership | Service | Residential customers (systemwide) | Residential price, 2024 | Commercial share of sales |
|---|---|---|---|---|---|
| Ameren Illinois Company | Investor Owned | Bundled | 1,060,894 | 15.26¢ | 28% |
| Corn Belt Energy Corporation | Cooperative | Bundled | 34,710 | 15.76¢ | 28% |
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 2
| Technology | Capacity | Share |
|---|---|---|
| Solar | 4 MW | 100% |
| Largest plants | Owner | Technology | MW | Since |
|---|---|---|---|---|
| Putnam Solar 1 | Pivot Energy | Solar | 2 MW | 2024 |
| Putnam Solar 1B | Pivot Energy | Solar | 2 MW | 2024 |
Retired since 2019
| Plant | Technology | MW | Year |
|---|---|---|---|
| Hennepin Power Station | Coal | 306 MW | 2019 |
The Putnam County labor market
| Industry (2025) | Jobs | Average pay | Concentration vs U.S. |
|---|---|---|---|
| All industries | 2,002 | $73,073 | 1.00 |
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 Putnam County
No data center, local measure or delayed project is on record in Putnam County. Illinois has 28 local measures on record statewide.
Putnam County and its neighbors
Of the 3 counties that border Putnam County, LaSalle 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 |
|---|---|---|---|---|---|---|
| Putnam County | 5,619 | ▲ 6.7% | 4 MW | — | — | — |
| Bureau County | 32,510 | ▼ 13.9% | 752 MW | 16 MW | — | — |
| LaSalle County | 107,773 | ▼ 7.2% | 2,824 MW | 322 MW | — | — |
| Marshall County | 11,473 | ▲ 1.3% | 146 MW | 178 MW | — | — |
More of Illinois
Putnam County, answered from the record
Who provides electricity in Putnam County, Illinois?
2 utilities have service territory in Putnam County in the EIA-861 2024 report: Ameren Illinois Company, Corn Belt Energy Corporation. The largest, Ameren Illinois Company, charged residential customers 15.26¢/kWh on average in 2024.
What power plants are in Putnam County?
2 operating plants with 4 MW of capacity. The largest is Putnam Solar 1 (2 MW, solar).
Are there data centers in Putnam County?
The SAVRN Data Center Map has no data center in Putnam County. The nearest activity on record is next door in LaSalle County.
Is Putnam County adding jobs?
Employers counted 2,002 jobs in 2025 against 1,877 in 2019 (+6.7%, BLS QCEW).
Does Putnam County have a data center moratorium?
No county-level measure is on record for Putnam County. Illinois has 28 local measures statewide, listed on the state page.