How Electricity Is Generated and Delivered Across the Hawaiian Islands

Hawaii has no statewide power grid. Each major island runs its own isolated system, so a plant on Oahu cannot send electricity to Maui, and a wind farm on Kauai cannot back up the Big Island. That single fact shapes how power plants are built, owned, permitted and listed across the state.

Our directory holds 75 power plant records for Hawaii. They include oil-fired generating stations, solar parks, wind farms, hydroelectric powerhouses and substations that feed distributed generation into the local grid. Kapolei on Oahu has the largest cluster, followed by Hilo, Honolulu, Kahuku and Lanai City. This page does not repeat those counts. It explains what the records mean and how the system behind them works.

Four main electricity providers cover the state. Hawaiian Electric serves Oahu. Maui Electric serves Maui, Molokai and Lanai. Hawaii Electric Light serves the island of Hawaii. The Kauai Island Utility Cooperative, usually called KIUC, serves Kauai and is owned by the members it serves. Hawaiian Electric, Maui Electric and Hawaii Electric Light are sister companies, while KIUC operates independently.

Many plants in the listings are not owned by those utilities at all. Independent power producers build solar and wind projects and sell the output under long-term power purchase agreements. The state Public Utilities Commission reviews those contracts. That is why Kahuku Wind Power, Kaheawa Wind Power II and the Kalaeloa Renewable Energy Park sit in the same directory as utility-run stations such as Miki Basin on Lanai and Port Allen on Kauai.

Who Regulates Hawaii's Power Plants and Which Laws Apply

The Hawaii Public Utilities Commission, known as the PUC, is the central regulator. It operates under Chapter 269 of the Hawaii Revised Statutes. The commission approves utility rates, reviews major generation and storage projects, and decides whether power purchase agreements are in the public interest. Most proceedings are open to the public, and filings are posted in dockets that anyone can read.

The Division of Consumer Advocacy, part of the Department of Commerce and Consumer Affairs, speaks for ratepayers in those cases. If you think a rate proposal or a new plant will affect your bill, that division is the state office that represents your interest. Individual customers can also file a complaint through the PUC about billing or service problems.

Environmental permits sit with other agencies. The Department of Health Clean Air Branch issues air permits for larger fuel-burning plants. The same department handles wastewater and storm water discharge rules. Hydropower projects such as Wailuku River Hydroelectric in Hilo, Wainiha Hydro near Hanalei and Kalaheo Hydro on Kauai also involve the Commission on Water Resource Management, because stream diversions are regulated in Hawaii.

Land use adds another layer. County planning departments handle zoning and special use permits, and projects on agricultural land may need extra approval. Larger projects often trigger an environmental assessment under Chapter 343 of the Hawaii Revised Statutes. That review includes a public comment period, which is the easiest point for neighbors to be heard.

State policy points in one direction. In 2015 Hawaii became the first state to set a goal of 100 percent renewable electricity, with a target date of 2045. The State Energy Office, within the Department of Business, Economic Development and Tourism, tracks progress. Because the islands have long depended on imported petroleum, much of the new construction you see in these listings is solar, wind, hydro or battery storage.

Metro Oahu Compared With the Neighbor Islands

Where a plant sits tells you a lot about what it does. Each county has its own character, and the differences affect access, noise, land use and the kind of facility you will find.

Oahu and Honolulu County

Honolulu County covers the whole island of Oahu and holds the largest share of our records. Kapolei, home to the Campbell Industrial Park area, leads the list. The Ewa Nui Substation DG at 91-1440 Farrington Highway is one Kapolei entry. Downtown, a record at 170 Ala Moana Boulevard marks the urban end of the system.

Renewables have spread across the rest of the island. Kahuku Wind Power on Kamehameha Highway sits on the North Shore. Kawailoa Solar is near Haleiwa. Ee Waianae Solar Project is on the Leeward coast, and Pearl City Peninsula Solar Park uses land near Pearl Harbor. The Kalaeloa Renewable Energy Park in Ewa Beach occupies part of the former Barbers Point naval air station. Helemano Substation DG in Wahiawa serves the central plain.

Maui, Molokai and Lanai

Maui County is unusual because it spans three islands, each with its own grid. On Maui, Kaheawa Wind Power II off Honoapiilani Highway near Wailuku harnesses strong trade winds above the west side. The Kahului record at 200 Hobron Avenue sits near the harbor, and Kihei Solar Farm is on South Kihei Road. Hana Substation serves the remote east side, where a single road links the town to the rest of the island.

Lanai City has four listings, including the Maui Electric Miki Basin Generating Station on Miki Road. Small island grids like this one depend on local generation, so plants tend to be close to the towns they serve.

The Big Island

Hawaii County is the largest island by area, and its plants are spread out accordingly. Wailuku River Hydroelectric in Hilo draws on one of the wettest watersheds in the state. Lalamilo Windfarm in Waimea and Hawi Wind Farm in North Kohala use the winds on the northern coast. Hamakua Energy Plant in Honokaa and the Keahole site in Kailua-Kona are generating stations on opposite sides of the island. Geothermal power from the Puna district, an energy source specific to this island, also feeds the grid.

Kauai

Kauai County has moved furthest toward solar and storage. Kiuc Kapaia PV and Battery Storage Project in Lihue, Krs I Anahola Solar and Krs II Koloa Solar all pair sunshine with batteries to cover evening demand. Wainiha Hydro and Kalaheo Hydro reflect the island's plantation-era water systems, and Port Allen in Eleele is a long-standing generating station on the south shore.

Finding and Using Power Plant Records in Hawaii

Most power plants are industrial sites rather than public offices. They are fenced, monitored and not open for drop-in visits. The listing is useful as a map of where energy infrastructure is, and as a starting point for contacting the right organization. A few practical steps help:

Keep in mind that some records come from historic or federal environmental datasets. The Ewa Sugar Mill listing in Kaumakani, for example, carries a legacy name and does not describe a power station open to the public. Confirm the current operator before you plan a trip, and never enter a fenced facility without permission.

Power plant facilities in Hawaii include a mix of federal, state, and municipally owned generation assets that contribute to the region's overall electricity supply. Hawaii's energy mix and the number of publicly owned facilities reflect the state's natural resources, regulatory environment, and historical development of its utility infrastructure.

Power Plant locations are available in 35 cities across Hawaii. They are spread across 4 counties.

Areas with the highest concentration of power plant locations include Kapolei, Hilo, Honolulu, often reflecting proximity to water resources, fuel supply infrastructure, or industrial demand centers.

Residents of Hawaii who are customers of a municipal or public power utility can contact their local power authority for billing assistance, energy efficiency programs, and information about planned outages or infrastructure upgrades in their service area.

Power Plant by Counties

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Residents of Hawaii who receive electricity service from a publicly owned utility can visit or contact that utility's customer service office to learn about outage reporting, billing options, and energy assistance programs. For information about a specific power generation facility in Hawaii, contacting the state's public utility commission is often the best starting point.

Browse Power Plant by county across Hawaii to find the nearest location.

Practical Notes for Hawaii Power Plant Sites: Weather, Access and Timing

Hawaii's climate and geography affect how power facilities operate, and they affect when and how you should contact them. Hurricane season runs from June through November, and strong storms, high surf and flash floods can interrupt service on any island. Keep a battery-powered radio, charged phones and a few days of water on hand. A neighbor-island home with a single access road, such as in Hana or on the Kauai North Shore, may wait longer for repairs when roads are blocked.

Wind and solar output in Hawaii change with the weather and the time of day. Utilities therefore rely on batteries, flexible generators and demand programs to keep supply steady. Customers on Oahu, Maui and Hawaii islands may be offered time-of-use rates or load-shifting programs. Check with your utility about which ones apply to you, since rules and incentives change over time.

If you need something done, prepare before you call. Have your account number, service address and meter number ready. For a solar or battery connection, a licensed contractor normally files the interconnection application with the utility. Allow extra time on Lanai, Molokai and in remote districts, where staff and equipment travel by barge or plane.

For property and zoning questions, start with the planning department of the relevant county. For electricity rates, reliability or complaints that the utility cannot resolve, go to the Public Utilities Commission. For air emissions or discharge concerns at a plant, the Department of Health is the right agency. Writing to the proper office, with the facility name and address from the listing, usually gets a faster response than a general inquiry.

Frequently Asked Questions About Power Plants in Hawaii

The Hawaii Public Utilities Commission regulates electric utilities under Chapter 269 of the Hawaii Revised Statutes. It approves rates, reviews new generation and storage projects and oversees power purchase agreements with independent producers. The Division of Consumer Advocacy in the Department of Commerce and Consumer Affairs represents ratepayers in those cases. Air and water permits for individual plants come from the Department of Health, while county planning departments handle zoning and land use. If you have a complaint, begin with your utility, then take it to the commission if the issue remains unresolved.

No. Each island operates its own separate grid, and there are no undersea cables linking them for everyday power sharing. That is why Lanai City has its own Miki Basin Generating Station, and why Kauai builds solar and battery projects such as the one in Lihue. Each island must produce enough electricity for its own needs, including backup capacity for storms and equipment failures. This setup makes local generation, storage and careful planning more important than on the mainland, where utilities can buy power from neighboring regions.

Most facilities are not open to casual visitors. Generating stations, substations and solar parks are fenced and monitored for safety and security. Some operators host school groups, professional visits or community events, but you must ask in advance. Contact the utility or project owner in writing, explain your group size and purpose, and expect to wear protective gear and follow escort rules. Roadside views of wind turbines, such as those near Kahuku or Hawi, are fine from public roads. Never enter a gated site without permission.

Hawaii has historically relied on imported petroleum to fire its generators, and fuel must travel across the Pacific. Because each island has a small, isolated grid, the state also lacks the economies of scale and interconnection that mainland utilities enjoy. These conditions keep costs high. The renewable energy goal for 2045 aims to cut that dependence by shifting toward solar, wind, hydro, geothermal and storage. Rates for each utility are reviewed by the Public Utilities Commission, and you can read the proposals in its public dockets.

You have several opportunities. County planning commissions hold hearings on zoning and special use permits, and they accept written and oral testimony. Larger projects may require an environmental assessment under Chapter 343, which has a published public comment period. The Public Utilities Commission also lets people submit comments on projects and contracts before it. Check your county's planning department for notices, and watch for state environmental review announcements. Submitting comments in writing, with the project name and your address, helps officials track and respond to your concern.

If a downed line is sparking, touching a vehicle or lying across a road, stay far away and call 911 first. For ordinary outages, use the outage number on your electric bill or the utility's website. Your provider depends on where you live: Hawaiian Electric on Oahu, Maui Electric on Maui, Molokai and Lanai, Hawaii Electric Light on the Big Island, and KIUC on Kauai. Report the address, what you saw and whether neighbors are affected. During storms, expect longer restoration times on islands with limited road access.

Yes. Any system connected to the grid needs utility interconnection approval, and your county will usually require a building or electrical permit as well. Your installer normally files the paperwork. The programs that govern how much credit you receive for exported power have changed over the years and vary by island, so ask your utility for its current options before you sign a contract. On circuits with a lot of existing solar, review can take longer and the utility may require equipment upgrades or limits on export.