Save money on your next flight

Skyscanner is the world’s leading flight search engine, helping you find the cheapest flights to destinations all over the world.

Hawaii is known for its beautiful beaches, lush landscapes, and reliance on imported fossil fuels for power. But how exactly does the Aloha State keep the lights on? If you’re curious to learn more, keep reading to understand Hawaii’s unique electricity situation.

In short, Hawaii gets the vast majority of its power from burning oil. This is because the islands are remote and lack their own energy resources. However, Hawaii has been rapidly expanding renewable energy in recent years to become more sustainable.

In this comprehensive guide, we’ll explore Hawaii’s electricity mix, the role of oil and renewables, power plants across the islands, plans to meet renewable energy goals, and outlooks for the future.

Hawaii’s Heavy Reliance on Imported Fossil Fuels

Oil Powers 3/4ths of Electricity Generation

Hawaii relies on imported petroleum for over 70% of its electricity generation. As an isolated island chain in the middle of the Pacific Ocean, Hawaii cannot access traditional energy resources like coal or natural gas through pipelines.

Instead, the state must have all fuel, including crude oil, shipped in by sea. This heavy dependence on shipped-in oil makes electricity prices in Hawaii the highest in the nation, over twice as expensive as the U.S. average.

Most of Hawaii’s power plants run on fuel oil or diesel. As recently as 2012, over 90% of Hawaii’s net generation came from petroleum. Increased adoption of renewable energy has brought the petroleum percentage down, but high shipping costs and limited storage capacity prevent Hawaii from fully transitioning off of fuel oil and diesel.

Challenges of an Island Electric Grid

Hawaii’s island geography poses unique challenges for its electricity grid. Each island has its own isolated grid, meaning there are limited options for sharing generation resources between islands. Within islands, the terrain restricts optimal sites for utility-scale power plants.

Building redundant transmission infrastructure is also difficult across Hawaii’s mountainous islands.

In addition, the small customer base on each island, with Oʻahu being the largest at ~1 million residents, means added costs for generators. High fixed costs of generation and delivery hardware must be spread across fewer ratepayers.

Ultimately, these island grid constraints contribute to Hawaii having America’s most expensive retail electricity.

High Electricity Prices

According to the U.S. Energy Information Administration (EIA), the average retail price for electricity in Hawaii is $0.33 per kilowatt-hour (kWh). This far exceeds the U.S. average retail rate of $0.14/kWh.

Costs are inflated by Hawaii’s reliance on imported petroleum, higher transmission costs, and extra generation needed to meet peak demand.

State Average Retail Electricity Rate
Hawaii $0.33 per kWh
California $0.22 per kWh
U.S. Average $0.14 per kWh

High electricity prices have spurred more renewable energy adoption in Hawaii. But the state still has a long way to go before it can shake off its dependence on costly shipped-in oil.

Expanding Renewable Energy

Abundant Solar and Wind Resources

Hawaii is blessed with abundant solar and wind resources that can be harnessed to generate clean, renewable electricity. The islands enjoy over 250 days of sunshine per year, with solar irradiation levels ranging from 5.0 to 6.5 kWh/m2 per day.

This makes Hawaii one of the top states for solar power potential. In addition, northeast trade winds blowing consistently across the islands, especially on Maui and Hawaii Island, create excellent conditions for wind energy.

According to a detailed renewable energy technical potential study by the National Renewable Energy Laboratory (NREL), Hawaii has the technical potential to generate over 400,000 GWh per year from solar PV systems and onshore wind turbines based on geographic constraints and system performance.

This is over 5 times higher than Hawaii’s current total electricity generation.

Key Renewables Targets and Goals

Hawaii has set ambitious renewable portfolio standards (RPS) to transition away from imported fossil fuels towards locally available clean energy sources. Under the latest RPS targets passed into law in 2021, each island must generate 30% of its electricity from renewables by 2020, 40% by 2030, 70% by 2040, and achieve a 100% renewable portfolio by 2045.

To catalyze renewable energy growth, legislators also established a Renewable Energy Infrastructure Program which offers power producers expedited interconnection review and financial incentives for qualified renewable energy projects >5 MW.

So far, over $1 billion has been allocated to help finance large solar and wind farms across the islands.

Growth of Rooftop Solar

In recent years, rooftop solar PV systems have seen tremendous growth among Hawaii residents thanks to declining panel costs and attractive net energy metering (NEM) policies. Under NEM, excess solar electricity generated during the day can be fed back to the grid in exchange for energy credits.

There are now over 100,000 rooftop solar installations in Hawaii, meeting about 18% of statewide electric demand as of 2022.

Going forward, community solar and solar+storage projects will open up renewable energy options for renters and other customers currently unable to install private systems. The Hawaii Public Utilities Commission has directed utilities to procure over 260 MW of community solar and over 370 MW of solar+storage by 2030 to expand renewable energy access.

Power Plants Across the Islands

Oahu’s Main Energy Hub

Oahu is home to Hawaii’s largest power plant – the AES Hawaii plant in Kalaeloa. This coal-fired plant can generate 180 MW of electricity, supplying about 20% of Oahu’s energy needs. However, there are plans to convert the plant to use biofuels by 2023 as Hawaii transitions away from fossil fuels.

In addition, Oahu has a number of power plants that run on imported petroleum. For example, the Kahe Power Plant on the Leeward coast houses several oil-fired generating units supplying up to 660 MW. Renewables like solar and wind are also growing – solar capacity on Oahu has expanded over 5-fold since 2015.

Maui’s Shift from Fossil Fuels to Renewables

The Maui Electric Company has made tremendous strides in adding renewable energy over the last decade. Today, wind and solar meet about 40% of Maui’s electricity demand, up from just 1% in 2008.

Key projects enabling this transition include the Kaheawa Wind Power farms, the Auwahi Wind project, and large utility-scale solar sites across the island. Going forward, there are plans to retire Maui’s last coal plant in 2024 and obtain 100% renewable energy by 2045.

Big Island’s Geothermal Energy

The Big Island is a leader in geothermal power thanks to its volcanic geography. The 38 MW Puna Geothermal Venture plant can power up to 10% of the island’s homes using steam and hot fluid tapped underneath the ground near Kilauea volcano.

However, supplying the Big Island’s energy needs remains challenging given its isolated location far from Oahu’s population center. Only about 60% of the island’s power comes from renewable sources today, below the statewide average.

Kauai Leads in Renewable Penetration

Tiny Kauai punches above its weight when it comes to renewable energy adoption. Thanks to its wealth of hydropower and solar resources, coupled with a small local population, about 70% of Kauai’s electricity already comes from renewable energy.

Key projects include the Port Allen Solar Facility, Hanalei River hydroelectric plants, a biomass generator, and multiple solar farms across the island. Kauai plans to convert fully to renewable energy and completely phase out fossil fuels for electricity by 2045.

Pathways to 100% Renewables

Phasing Out Coal and Oil

Hawaii has set a goal to reach 100% renewable energy by 2045. A major part of this transition involves phasing out the use of coal and oil for power generation. As of 2022, roughly 15% of Hawaii’s electricity still came from burning oil.

However, the state plans to convert all oil-fired plants to use biofuels by 2045.

For example, Hawaiian Electric has already transitioned some oil-powered plants to use biodiesel made from used cooking oil. Further efforts are underway to expand local biofuel production from crops like dendê palm oil.

Using local biofuel sources will improve energy independence and keep money circulating in Hawaii’s economy.

Grid Modernization and Storage

Modernizing Hawaii’s grids and expanding energy storage capacity are crucial to enabling higher levels of renewable penetration. Old transmission lines are being upgraded to handle more intermittent wind and solar generation flowing between islands.

Battery storage systems like the Kapolei Energy Storage facility act as a buffer to smooth out renewables’ variability. With over 580 megawatt-hours of storage operating or under construction, Hawaii currently leads the U.S. in energy storage on a percentage basis.

Advanced grid technologies like advanced metering infrastructure (AMI) and distribution automation allow greater real-time visibility and control over energy supply and demand. For example, AMI supports time-of-use rates to incentivize load shifting to match renewable generation cycles.

Electrifying Transportation

Transportation accounts for over two-thirds of Hawaii’s petroleum use. Transitioning vehicles to electricity from renewable sources is thus essential for Hawaii to kick its oil addiction. Government rebates, EV charging infrastructure expansion, and outreach campaigns are accelerating EV adoption.

For example, Hawaii has over 100 DC fast charging ports open to the public, allowing EV drivers to recharge in as little as 30 minutes. An estimated 20% of registered light-duty vehicles in Hawaii will be electric by 2030 as costs continue falling.

Electrifying other transport like buses and ferries is also underway. For example, Hawaiian Electric and the Hawaii Department of Transportation are working to electrify buses and install charging systems on Oahu, Maui and Hawaii Island.

Expanding Biofuels

As mentioned above, transitioning oil-fired power plants to use locally produced biofuels will play an integral role in Hawaii’s renewable shift. Dendê and other palm oil crops can provide cheap, efficient biofuel feedstock without competing with food crops.

Hawaii’s tropical climate also presents opportunities for algae-based biofuels. For example, researchers at the Pacific Northwest National Lab are developing methods to sustainably farm algae offshore that can yield billions of gallons of biodiesel or jet fuel.

Combining biofuels with carbon capture systems could even produce negative-emissions fuels to offset aviation and shipping emissions. Biofuels coupled with electrification and renewable power sources like geothermal, solar, wind and hydropower can enable Hawaii to achieve its bold yet attainable 100% renewable target.

The Future of Hawaii’s Electricity

Reaching Renewables Goals

Hawaii has some of the most ambitious renewable energy goals in the United States, targeting 100% renewable electricity by 2045. To reach this, the state is expanding solar, wind, geothermal and other renewable generation, supported by battery storage to enable high penetrations of variable renewables.

As of 2021, around 37% of Hawaii’s electricity came from renewable sources. This puts Hawaii far ahead of most other states. Hawaii’s isolated island grids also provide opportunities to pilot new renewable energy and storage technologies before deploying them elsewhere.

Emerging Technologies

Several cutting-edge technologies could help Hawaii reach even higher renewable penetrations in future:

  • Advanced solar PV panels and solar thermal generation, able to provide power 24/7
  • New large-scale battery chemistries better suited for grid storage
  • Innovative pumped hydro storage using seawater on Oahu
  • Floating offshore wind farms sited far out at sea
  • Enhanced geothermal systems accessing very hot rock deep underground
  • Green hydrogen production for clean fuel and long-duration energy storage
  • With its abundance of sun, wind and volcanic activity, Hawaii has immense potential for renewable power. Adoption of emerging technologies could help the state meet and even exceed its 100% renewable target over the coming decades.

    Resilience and Affordability Considerations

    While adding renewable sources, Hawaii must also ensure its electricity system remains resilient during extreme weather events. Severe storms, flooding and wildfires may become more likely with climate change.

    Strategic hardening of grid infrastructure will be required. Distributed solar and battery storage can also provide backup power if parts of the grid are damaged.

    Affordability is another key consideration. Adding renewables requires major up-front investments that can increase electricity rates. Community solar, battery leasing programs and financial incentives can help limit bill impacts, especially for low-income residents.

    Year % Renewables Avg. Electricity Price
    2015 24% $0.33 per kWh
    2021 37% $0.36 per kWh

    Balancing renewable energy growth, resilience and affordability will be crucial to realizing Hawaii’s bold vision for the future of its electricity system.


    In conclusion, Hawaii relies heavily on imported petroleum to meet electricity demand today. But the state has committed to a renewable energy transformation and continues working towards a clean energy future.

    By tapping its wealth of solar, wind, and geothermal resources and modernizing its isolated island grids, Hawaii aims to reach 100% renewables in the coming years. This transition will increase sustainability and energy independence for the people of Hawaii.

    Sharing is caring!

    Similar Posts