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Data center project · Rock County, Wisconsin

Viridian data center proposal, former GM/JATCO site, Janesville

Withdrawn · Janesville ended talks with Viridian on an $8 billion hyperscale campus at the old GM plant; a Nov. 3, 2026 referendum would require voter approval for large projects there.

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Status
Withdrawn · as of June 22, 2026
Location
City-owned former General Motors Janesville Assembly Plant, 1000 General Motors Drive · Rock County
Status note
Council let the letter of intent expire; the city says there are no active proposals for the site.
Power
800 MW
800 MW, 11-building campus as described in reporting on the proposal (Ballotpedia, The Gazette); not a backup-generator figure.
Land
250 acres
Investment
About $8 billion (reported)
Developer and team
Viridian Partners (Viridian Acquisitions)
Evidence
News reports; primary records not yet obtained
Size class
50 MW or more (tracker scope)
Map position approximate, from the reported address or area. Updated Oct. 17, 2026.

Updates, newest first

  1. June 22, 2026 The council unanimously let the letter of intent expire and voted to develop data center guardrails. (Spectrum News 1, June 25, 2026; The Gazette (Janesville), July 1, 2026)
  2. Feb. 9, 2026 The council placed a citizen initiative on the Nov. 3 ballot requiring voter approval for projects over $450 million at the site. (Ballotpedia News, Feb. 12, 2026)
  3. Nov. 10, 2025 The city council approved a 120-day letter of intent with Viridian Acquisitions, 5-2. (WKOW 27 News, Nov. 11, 2025)

Conflicts and open questions

  • The Gazette describes the former GM and JATCO sites as about 240 acres; Spectrum News and a council member cite 250 acres. Upper value stored.

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