Waiau
Oil power plant in Honolulu County, Hawaii. 374.6 MW of nameplate capacity across 6 generators, operated by Hawaiian Electric Co Inc.
Also known as Pearl City Waiau Power Plant · EIA plant 766
Analyst: free account, 1 question a day.
Key facts
- Capacity
- 374.6 MWNameplate
- Generators
- 6 operatingEIA-860M, August 2026
- Operating since
- September 1959First generator online
- Operator
- Hawaiian Electric Co IncEIA operator ID 19547
- Grid
- Not reported
- Price nodes
- None linkedNo verified ISO node
- Location
- Honolulu County, HI21.3890, −157.9615
- EIA plant ID
- 766EIA plant page
Data as of EIA-860M August 2026 (published 2026-09-24). Capacity is nameplate, not live output.
How much power Waiau produces
Free · EIA-923Net generation, 2025
975 GWh
974,784 MWh, final
Capacity factor, 2025
29.7%
2024: 23.8%
January to July 2026
377 GWh
Provisional. 5 of 7 months reported
Range, 2015 to 2025
0.7–1.3
TWh a year. Low 2020, high 2023
| Year | Net generation, MWh | Capacity factor | Months reported |
|---|---|---|---|
| 2000 | 988,982 | Not reported | 12 of 12 |
| 2001 | 1,192,201 | Not reported | 12 of 12 |
| 2002 | 1,316,509 | Not reported | 12 of 12 |
| 2003 | 1,204,246 | Not reported | 12 of 12 |
| 2004 | 1,276,518 | Not reported | 12 of 12 |
| 2005 | 1,324,694 | Not reported | 12 of 12 |
| 2006 | 1,310,833 | Not reported | 12 of 12 |
| 2007 | 1,342,673 | Not reported | 12 of 12 |
| 2008 | 1,243,365 | Not reported | 12 of 12 |
| 2009 | 1,389,616 | Not reported | 12 of 12 |
| 2010 | 1,137,655 | 27.4% | 12 of 12 |
| 2011 | 1,023,270 | 24.6% | 12 of 12 |
| 2012 | 1,041,501 | 25.0% | 12 of 12 |
| 2013 | 1,035,919 | 24.9% | 12 of 12 |
| 2014 | 759,923 | 27.2% | 8 of 12 |
| 2015 | 1,191,029 | 28.6% | 12 of 12 |
| 2016 | 912,935 | 21.9% | 12 of 12 |
| 2017 | 912,198 | 21.9% | 12 of 12 |
| 2018 | 983,895 | 23.7% | 12 of 12 |
| 2019 | 1,002,196 | 24.1% | 12 of 12 |
| 2020 | 736,867 | 17.7% | 12 of 12 |
| 2021 | 891,617 | 21.4% | 12 of 12 |
| 2022 | 904,821 | 21.8% | 12 of 12 |
| 2023 | 1,283,645 | 30.9% | 12 of 12 |
| 2024 | 991,273 | 23.8% | 12 of 12 |
| 2025 | 974,784 | 29.7% | 12 of 12 |
| 2026 (provisional, partial year) | 377,415 | 26.4% | 5 of 7 |
* 2026 covers January to July and is provisional. Capacity factor is net generation divided by nameplate capacity times the hours of each reported month.
Power prices and basis
Free accountNo verified ISO price node is linked to this plant, or its price history could not load.
Emissions
Free · EPA CAMPDNo EPA emissions units are linked to this plant.
Water use
Free · EIA-923 cooling, USGSWithdrawal, 2024
81,393
million gallons
Consumption, 2024
Not reported
million gallons
Source
Pearl Harbor
Surface, Saline. Once-through
36 of 36 cooling months report withdrawal. Saline, brackish or ocean intake; not tested. Blank volumes are unreported, not zero.
Generators
Free · EIA-860M| Generator | Technology | Nameplate MW | Online since |
|---|---|---|---|
| W5 | Petroleum Liquids | 54.4 | September 1959 |
| W6 | Petroleum Liquids | 54.4 | June 1961 |
| W7 | Petroleum Liquids | 81.6 | October 1966 |
| W8 | Petroleum Liquids | 81.6 | November 1968 |
| W9 | Petroleum Liquids | 51.3 | June 1973 |
| W10 | Petroleum Liquids | 51.3 | December 1973 |
Ownership and offtake
ProOwnership and offtake are part of Pro
Owners and their shares, parent companies, and power purchase agreements with their buyers. EIA-860M lists Hawaiian Electric Co Inc as the operator, which is not always the owner.
Modeled data
ProPro adds modeled values for this plant. Everything above stays free.
Generation potential vs reported
Monthly potential at seasonal net capability, next to EIA-923 output. Shows how much of the plant's capability was used.
300 analyst questions a month, plus MCP
Query Waiau and 14,224 other projects from Claude or your own tools. Free accounts get 1 question a day.
Power plants near Waiau
More plants operated by Hawaiian Electric Co Inc
Questions about Waiau
How much power does Waiau produce?
Waiau reported 974,784 MWh (975 GWh) of net generation in 2025, a 29.7% capacity factor on 374.6 MW of nameplate capacity. From January to July 2026 it reported 377 GWh, which is provisional.
Where is Waiau?
Waiau is in Honolulu County, Hawaii, at 21.3890, −157.9615.
Who operates Waiau?
EIA-860M for August 2026 lists Hawaiian Electric Co Inc as the operator (EIA operator ID 19547). The operator is not always the owner.
When did Waiau start operating?
Its first generator began operating in September 1959, according to EIA-860M.
Sources
- EIA-860 2025 (final) and EIA-860M August 2026: plant, generators, capacity, operator and location
- EIA-923 monthly net generation, 2000 to July 2026 (2026 provisional)
- EIA-923 cooling water 2024 and the USGS surface water supply and use index, Water years 2010-2020 (Oct 2009 to Sep 2020), mean of monthly values
- Plant names from OpenStreetMap, © OpenStreetMap contributors (ODbL)
Page updated 2026-10-04 from the InfraMap data build. Methodology · Data sources · EIA plant page