Data Center Census

Grayslake, Lake County, IL

T5 @ Chicago IV

ApprovedVillage issued first building permit Sept. 1, 2026; lawsuit challenging approvals pending
  1. Rumored
  2. Proposed
  3. Approved
  4. Under construction
  5. Operating

The T5 @ Chicago IV campus in Grayslake, as approved by the Village Board between September 2024 and May 2025, calls for up to 472 acres of development, more than 10 million square feet of buildings and an electrical demand of approximately 1.55 gigawatts supplied by ComEd. Village officials describe an expected $18 billion multi-building private investment, and the village issued the first building permit, for an 800,000-square-foot facility, on Sept. 1, 2026. A lawsuit filed in Lake County Circuit Court by the Preservation of Community Well-being Collective LLC and nine Lake County residents challenges the village's approvals.

Key facts

Size & schedule

Planned capacity1.55 GW [4]
approximate electrical demand supplied by ComEd
Source excerpt
“calls for up to 472 acres of development, more than 10 million square feet of buildings and an electrical demand of approximately 1.55 gigawatts of power supplied by ComEd”
Planned capacity480 MW [1]
critical IT capacity for a 160-acre site as announced by T5 in May 2024, before the approved expansion to 472 acres
Source excerpt
“The 160-acre site will support up to 480 megawatts (MW) of critical IT capacity across multiple data center buildings.”
Site size472 acres [4]
up to
Source excerpt
“calls for up to 472 acres of development, more than 10 million square feet of buildings and an electrical demand of approximately 1.55 gigawatts of power supplied by ComEd”
Floor area10.1 million sq ft [3]
as much as
Source excerpt
“In Grayslake, the T5 project calls for as many as 18 buildings totaling as much as 10.1 million square feet.”
Buildings18 [3]
as many as
Source excerpt
“In Grayslake, the T5 project calls for as many as 18 buildings totaling as much as 10.1 million square feet.”
Stated investment$18 billion [4]
expected, per village officials
Source excerpt
“The first facility, spanning 800,000 square feet, marks the operational start of an expected $18 billion multi-building private investment, village officials said.”
Target completionFirst 60MW in Q4 2027 (as announced May 2024) [1]
Source excerpt
“the first 60MW of data center capacity in Q4 2027”

Power

UtilityComEd [4]
Source excerpt
“an electrical demand of approximately 1.55 gigawatts of power supplied by ComEd, with associated diesel backup generation infrastructure.”
Backup generatorsdiesel backup generation infrastructure [4]
Source excerpt
“an electrical demand of approximately 1.55 gigawatts of power supplied by ComEd, with associated diesel backup generation infrastructure.”

Money & incentives

Tax incentivesNone: secured without local municipal tax incentives, tax exemptions or TIF subsidies (per village); projected $1.4 billion in property tax revenue over 20 years [3]
Source excerpt
“Secured without local municipal tax incentives, tax exemptions or TIF (tax increment financing) subsidies, the development is projected to generate $1.4 billion in property tax revenue over 20 years across local taxing bodies”

Local decisions & site

Deciding voteApproved by the Grayslake Village Board between September 2024 and May 2025 [4]
Source excerpt
“The T5 @ Chicago IV campus, as approved by the Grayslake Village Board between September 2024 and May 2025”
Parcel / addressCornerstone property along Peterson Road and Alleghany Road [4]
Source excerpt
“The Village of Grayslake said Tuesday that it issued the initial building permit for the first facility at the T5 campus within the Cornerstone property along Peterson Road and Alleghany Road.”

Figures are as stated by the cited source. Where sources disagree, each figure is shown.

Upcoming hearings

  • Oct 30, 2026 — Lake County Circuit Court: Initial status hearing in lawsuit challenging the village's approvals (9 a.m., Courtroom 301) [4]

Timeline

  1. T5 announces a 480 MW data center campus in Grayslake [1]

  2. Grayslake Village Board completes approvals of the campus (approved between September 2024 and May 2025) [4]

  3. Preservation of Community Well-being Collective LLC and nine Lake County residents sue to challenge the village's approvals [4]

  4. Village issues first building permit, for an 800,000-square-foot facility [4]

Issues raised

  • Objectors cite inadequate public hearings and concerns about power and water usage [2]
  • A lawsuit seeks to invalidate the 2024–2025 approvals and block further permits [3][4]

Sources

  1. T5 Data Centers Announces Further Expansion into Chicago Suburbs with New 480 MW Data Center Campus
    T5 Data Centers · May 2, 2024 · company
  2. Despite village approvals, legal action expected against Grayslake data center
    Daily Herald · Jun 8, 2026 · news
  3. Defying trends, Grayslake welcomes start of massive data center project
    Daily Herald · Sep 1, 2026 · news
  4. Grayslake issues first permit for construction to begin on mega data center campus as lawsuit seeks to block development
    Lake and McHenry County Scanner · Sep 1, 2026 · news