Data Detective: Illinois’ Nuclear Edge—How Illinois Combines Scale With Clean Electricity

 

Welcome back to Data Detective, where we walk step by step through public data to uncover what’s really happening in Illinois’ economic landscape.

This month, we’re plugging into Illinois’ power grid. Clean energy access has become a deciding factor for companies choosing where to locate operations, and Illinois is regularly cited as a leader—but what does the public data show?

This raises the question:

How carbon-free is Illinois’ electricity?

To answer that, we’ll turn to the U.S. EPA’s Emissions & Generation Resource Integrated Database (eGRID).

Step 1: Navigating EPA Data

Start at the EPA’s eGRID homepage and download the most recent Summary Data release. In this instance, we’ll be working with the 2023 data.

Open the workbook and head to the Table 4 tab. This is the state-level summary, covering states’ generation resource mixes.

Step 2: Understand the Dataset

Columns include each state’s total annual net generation in MWh, nameplate capacity in MW, and a fuel-by-fuel breakdown by energy type as a percentage.

NOTE: eGRID tracks nuclear separately from “renewables” (wind, solar, hydro, biomass, geothermal). Both are carbon-free at the point of generation, so we’ll look at them together as Illinois’ full clean-energy picture.

Step 3: Pull Illinois’ Numbers and Benchmark

Upon locating Illinois’ data, we find that the state generated:

• 7 million MWh in total net generation (#5 in the U.S.)
• Nuclear energy accounts for 9% of the state’s entire generation mix
• Multiplying Illinois’ total generation by its nuclear share shows Illinois generated:
  • 6 million MWh in nuclear generation (#1 in the U.S.)

Illinois’ nuclear fleet alone generated roughly 22 million MWh more than the #2 state, Pennsylvania, with nearly 30% greater generation power than this competitor.

Step 4: Add in Renewables

Combine nuclear with wind, solar, hydroelectric and biomass generation, and Illinois’ total carbon-free share of generation reaches 68.5% of its output.

More than two out of three megawatt-hours generated in Illinois in 2023 came from a source that produced no carbon emissions at the point of generation.

NOTE: Illinois ranks 5^th nationally for wind generation!

Step 5: Compare Emissions Intensity Across the Midwest

Navigate to Table 3—this table contains total output emission rates in lb/MWh. Filter the CO2 output emission rate column to Midwest states, and sort ascending.

Illinois’ rate of 471.7 lbs of CO2 per MWh is the #2 lowest rate in the Midwest. The results are even more fascinating when observing scale. Illinois’ grid is roughly a third as carbon-intensive as neighboring Indiana and Missouri, while generating nearly double Indiana’s total output and more than 2.5 times Missouri’s.

Illinois proves that states can provide both clean energy generation and industrial-scale output.

Key Takeaway

Illinois’ grid produced more energy than all but four other states in 2023 at 177.7 million MWh, and kept over two-thirds of it carbon-free. This combination of such a massive scale is rare and valuable for companies evaluating carbon-conscious operations. Companies locating in Illinois don’t have to choose between grid capacity and clean power—they get both!

Get Curious

What data would you like our Research Team to tackle next? Let us know, and we’ll dive in.

Until next time!