Merwin — Plant Summary
- EIA Plant ID
- 3847
- Capacity
- 136 MW
- Primary Fuel
- Hydro
- Technology
- Conventional Hydroelectric
- Status
- Operating
- Location
- Cowlitz, WA
- Operating Since
- 1931
- Generators
- 4
- Operator
- PacifiCorp
- Parent Company
- Berkshire Hathaway
- Annual Generation
- 467,317 MWh
- Capacity Factor
- 39.2%
- Balancing Authority
- PacifiCorp - West
- ISO/RTO
- —
- NERC Region
- WECC
Merwin
OperatingHydro
Ranked #19 of 75 Hydro plants in WA#140 of 1454 nationally
136 MW Hydro operating in Cowlitz, WA — PacifiCorp - West
EIAGEMWD
136 MW
Nameplate Capacity
4
Generators
units
Conventional Hydroelectric
Technology
1931
Operating Since
Location
Ownership & Operator
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | PacifiCorp | Pacific | — |
| Owner(s) | PacifiCorp | Berkshire Hathaway | — |
| Status | Operating | operating | — |
Ownership Chain
About
Merwin Dam is a concrete arch gravity-type hydroelectric dam on the Lewis River, in the U.S. state of Washington. It is located on the border between Cowlitz County and Clark County. Its reservoir is called Lake Merwin.
Read more on WikipediaMerwin is a 136 MW hydroelectric power plant located in Cowlitz County, Washington. The plant began operating in 1931 and consists of 4 generators utilizing conventional hydroelectric technology. The primary fuel source is water (WAT). PacifiCorp, a subsidiary of Berkshire Hathaway, operates the facility. Merwin ranks 19th out of 23 power plants in Washington and 140th out of 194 nationally. The plant operates within the PacifiCorp - West balancing authority and the Western Electricity Coordinating Council (WECC) NERC region.
In the latest year of reported generation, Merwin produced 467,317 MWh of electricity, achieving a capacity factor of 39.2%. Financial data indicates an installed cost of $1305.66 per kW. The power purchase agreement (PPA) price is $10.78 per MWh. Financial data is sourced from FERC and FERC Electric Quarterly Reports (EQR).
Generated from EIA, GEM, and public data sources
Engineering & Generators
Grid Context
NERC Region
WECC
Balancing Authority
PacifiCorp - West
Grid Voltage
115 kV
Regulatory Status
RE
Entity Type
Investor-Owned Utility
Sector
Electric Utility
Generation
60.7K MWh
Latest Month
467.3K MWh
Annual Generation
39.2%
Capacity Factor
Jan 2022 – Dec 2024
Financial DataBeta
Source: FERC Form 1, FERC Electric Quarterly ReportsHIGH
$10.8/MWh
PPA Price
PacifiCorp
Contract Seller
Cumulative Installed Cost
Per-Unit Cost Trends
Pricing & Market Data
This plant is outside organized wholesale electricity markets (ISOs/RTOs). Nodal pricing data is not available.
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