All industries › Onshore wind › California › MATTERHORN
Onshore wind · Riverside County, California
MATTERHORN
A 407 MW onshore wind project in Riverside County, California. MATTERHORN has asked to connect to the grid or filed for its first approvals; nothing on record yet commits money to it. No public record read so far names its builder.
The record
What the public record says about MATTERHORN, as of 25 Oct 2026.
| Stage | Queued |
|---|---|
| Construction start | Q2 2028 estimate |
| Size | 407 MW |
| Location | Riverside County, California (to about 10 km) |
| Developer | Not named in any record read |
| Grid operator | CAISO |
| Builder (EPC) | Not named yet |
| Trade subcontractors | in the app |
| People to call | in the app |
| Phase windows | in the app |
Every fact in the app links to the public record behind it, with how many records agree and whether it is confirmed, reported or an estimate. What the terms mean.
What happened
Each change dated by the scene or the document, newest first.
No change on record since Groundtrace started tracking it.
Who was named on it, and when, is in the app.
Also in Riverside County
| Project | Stage | Size |
|---|---|---|
| GRACE ENERGY CENTERUtility solar | Under construction | 509 MW |
| ATHOS POWER PLANTUtility solar | Under construction | 450 MW |
| SE Athos IIBattery storage | Under construction | 402 MW |
| EASLEYUtility solar | Under construction | 290 MW |
| COBALTUtility solar | Under construction | 256 MW |
| DOUBLE BUTTE STORAGEBattery storage | Financed | 508 MW |
More
Questions
MATTERHORN, in short.
Where is MATTERHORN?
MATTERHORN is a 407 MW onshore wind project in Riverside County, California, in CAISO's interconnection queue. The public page places it to within about ten kilometres; the precise location is in the subscriber record.
When does construction start on MATTERHORN?
Groundtrace estimates construction starts in the second quarter of 2028. This is an estimate from the project's filings, not a date any record states; the exact date and the record behind it are in the subscriber record.
Who is developing MATTERHORN?
No public record read so far names its developer.
Who is building MATTERHORN?
No public record read so far names a builder for MATTERHORN. Groundtrace leaves the field empty rather than guess, and fills it when a permit, a filing or the builder's own page names one.
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