Why This Site

New power generation needs three things: land, a connection to the grid, and transmission to move the power. Assembling them from scratch takes years. The Hennepin plant site already has the land and the transmission, and an established point of interconnection to build from.
The Hennepin Power Plant has occupied this property in Putnam County for decades. The site carries established transmission equipment connecting it to the regional grid.
The Hennepin Power Plant has retired. Vistra announced the closure in August 2019, one of four Illinois plants retired to comply with the state’s revised Multi-Pollutant Standard rule governing emissions across the fleet.
Placing new assets on ground like this reuses infrastructure that already exists instead of building it somewhere else from nothing.
The Hennepin plant site, Putnam County, Illinois.

What Is Under Consideration

TechnologySolarUtility-scale solar generation.
Capacity under evaluation24MWSolar capacity being evaluated for the site.
CountyPutnamPutnam County, Illinois.
Project scope changes as development work proceeds, and no decision to construct has been made. Any project at the Hennepin site would depend on market conditions, permitting, interconnection and other approvals.

What a Project Here Would Mean

Building a project at the Hennepin site would deliver a one-time economic stimulus to Putnam County — capital investment at the site, wages for local trades, and spending through the local supply chain.
The figures below are what that was modeled to produce.
Capital investment$70MModeled investment at the plant site.
During construction64Jobs supported in Putnam County over the construction period.
Local earnings$5.5MEarnings for local workers during construction.
Local economic output$7.5MAdded economic activity in the county during construction.
Economic impact figures were modeled for Vistra by Dr. David G. Loomis, Strategic Economic Research, LLC.

This Has Been Done Four Times in Illinois So Far

Hennepin is a proposal. The approach and the company behind it are not.
Baldwin68 MW of solar with energy storage in Randolph County, operating.
Newton52 MW of solar with energy storage in Jasper County, operating.
Coffeen44 MW of solar with energy storage in Montgomery County, operating.
Pulaski405 MW of solar in Pulaski County, completed in 2026 and generating power.
Vistra’s recent investments of more than $1 billion have added 570 MW of generation and 6 MW / 24 MWh of battery storage across Illinois.

Hennepin Site at a Glance

Location13498 E 800th Street, Hennepin, IL 61327
CountyPutnam County, Illinois
Plant statusRetired 2019 under the state’s Multi-Pollutant Standard rule
Identified opportunityUtility-scale solar
Capacity under evaluation24 MW
InterconnectionExisting plant interconnection and transmission

Questions About the Hennepin Site

No. A utility-scale solar project has been under development for the site, but no decision to construct has been made. Energy projects of this size take years of diligence, engineering, permitting and interconnection work before anyone breaks ground.

Because a retired plant site does not start from zero. New energy assets need land, a connection to the grid and transmission to carry the power away, and assembling those three from scratch can take the better part of a decade. The Hennepin plant site has the land and the transmission, and a project there would reuse some of the transmission and interconnection assets already in place. New substation work and, in almost all cases, a new point of interconnection are still required.

Yes, four times. Baldwin, Newton and Coffeen pair utility-scale solar with energy storage on existing plant property and are operating today. Pulaski Solar, a 405 MW facility in southern Illinois, reached commercial operation ahead of schedule.

Modeling for a redevelopment project at the Hennepin site estimated 64 jobs supported in Putnam County during construction, $5.5 million in earnings for local workers and $7.5 million in added local economic output.