Four Mile Hill

Brownfield

Siskiyou, California · Calpine Corporation

Legacy capacity
50
MW

Four Mile Hill is a former geothermal site in Siskiyou, California. Retired generation sites are among the most attractive datacenter redevelopment targets: the existing interconnection was sized for roughly 50 MW of generation, so the grid hookup, transmission rights, and often cooling-water access are already in place — collapsing the speed-to-power timeline versus a greenfield build.

Former use & capacity

Former useformer geothermal site
Site typeretired_plant
Existing capacity50 MW
EIA plant ID#55845

Grid hookup & remediation

Nearest substation32.2 mi
OperatorCalpine Corporation
Operator addressHighway 139 and County Road 97, n/a, CA, 96097
Why this site is datacenter-attractive: a former geothermal site of this scale leaves behind a high-capacity grid interconnection that a new load can re-use, frequently shaving years off the interconnection queue. Retired-plant sites also tend to be already zoned for heavy industrial use with established road, rail, and water infrastructure.

Nearby datacenter candidate sites

Scored candidate sites near Four Mile Hill, ranked by DC Readiness.

Candidate sites near Four Mile Hill
SiteTypeStateCountyVoltageCapacityQueue waitScore
Greenfield (OLINDA - CAPTAIN JACK)GreenfieldCAModoc County500 kV1,000 MW5.7 yrs54.5
Greenfield (OLINDA - CAPTAIN JACK)GreenfieldCAModoc County500 kV1,000 MW5.7 yrs53.8
Greenfield (OLINDA - CAPTAIN JACK)GreenfieldCAModoc County500 kV1,000 MW5.7 yrs53.5
Greenfield (MALIN - ROUND MOUNTAIN)GreenfieldCAShasta County500 kV1,000 MW5.7 yrs53.4
Greenfield (MALIN - ROUND MOUNTAIN)GreenfieldCAModoc County500 kV1,000 MW5.7 yrs53.1
Greenfield (MALIN - ROUND MOUNTAIN)GreenfieldCAModoc County500 kV1,000 MW5.7 yrs52.5
Greenfield (MALIN - ROUND MOUNTAIN)GreenfieldCAModoc County500 kV1,000 MW5.7 yrs51.4
Greenfield (OLINDA - CAPTAIN JACK)GreenfieldCAShasta County500 kV1,000 MW5.7 yrs51.2

See all datacenter sites in California

Dataset updated . Screening estimates derived from public data sources.

Brownfield attributes are derived from EIA retired-generator and EPA public data. Existing capacity reflects the retired plant's historical nameplate, not deliverable interconnection for a new load. Confirm reusable interconnection rights, remediation status, and site availability with the utility, ISO, and current owner.

Go deeper than the public screen

This page shows a public slice of the GridCensus dataset for Four Mile Hill, Siskiyou, California. Pro and Enterprise plans unlock the full 164,098-site catalog, raw sub-scores, parcel ownership, interconnection-queue detail, saved searches, and programmatic API access.