Illinois Data Center Power Play
How Clean Energy Can Meet Rising Electricity Demand While Delivering Climate and Health Benefits
Union of Concerned Scientists | January 2026
Electricity demand is projected to surge in Illinois. In the short
term, the emergence of artificial intelligence for training and
using large language models has resulted in proposals to build
increasingly large “hyperscale” data centers that can consume as
much electricity as entire cities. In the longer term, electrifica-
tion of economic sectors will drive up electricity demand even
further.
How Illinois responds to growing electricity consumption
will significantly affect how it achieves its clean energy goals
under the 2021 Climate and Equitable Jobs Act (CEJA). That
landmark legislation seeks to gradually reduce heat-trapping
emissions from fossil fuel power plants in the state to zero by
2045 (Collingsworth 2021). CEJA and subsequent energy laws
also promote the development of renewable resources in Illinois
to replace the electricity generated by retiring coal and gas
plants. Yet the rapid increase in demand from data centers could
drive up emissions from Illinois power plants, and it could also
increase the state’s reliance on out-of-state electricity generation
rather than building more clean energy itself.
The Union of Concerned Scientists (UCS) explored how
Illinois can meet new electricity demand by utilizing policies
and pathways that prioritize the needs of its residents to access
clean energy. We focused on the role of data centers and the
implications for Illinois’ energy system of rapid—and highly
uncertain—data center load growth.
Read or download the full report below:
