Mahi Solar & Storage Project

The Mahi Solar project is on track to be the largest renewable project in Hawaii, supplying enough clean energy to power 40,000 O‘ahu homes. Selected by Hawaiian Electric Company (HECO) in 2024, the project is located in Kunia and will integrate farming and ranching around and under the solar panels. Previously postponed in 2022 because of the global supply chain crisis, Mahi Solar is now scheduled to begin construction in late 2026 and begin operating by the end of 2028.

Developed by Longroad Energy, the Mahi Solar project signed a Power Purchase Agreement (PPA) with HECO in November 2025, which has been sent to the Hawaii Public Utilities Commission for review and approval. Most other permits from the State and City and County have been approved, and the project is now in final engineering and will soon be applying for building permits. Mahi Solar has been guided by years of discussions with many community members in Kunia and the surrounding area, recommending that the project provide community benefits through opportunities for local farmers and support for agriculture in Hawaii.

Past Events

Mahi Solar Public Meeting 3/13/24

View Meeting

https://vimeo.com/925599357?share=copy

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Project Description

Longroad Energy is designing the Mahi Solar project to produce clean energy and support local agriculture in Kunia, O‘ahu. At 120 MW(ac), this project could produce 4% of the island’s electricity annually, enough to power 40,000 local homes, enabling HECO to burn less fossil fuel and emit less greenhouse gasses. The project includes a 480 MWh (4-hour) battery system to store solar energy generated during the day and provide power at night, and a new substation and transmission line extension to connect to the O‘ahu grid. Mahi Solar is scheduled to be completed by the end of 2028.

Our team at Longroad (previously as First Wind) worked successfully with local communities to develop 7 of Hawaii’s largest energy projects. The Mahi Solar project will work with local farmers to raise crops and livestock between and under PV panels. The project would occupy 617 acres across several parcels of land, on the Ewa (west) side of Kunia Road. The project would create approximately 200 jobs during construction and another 2-3 long-term positions during operations, in addition to new jobs related to farming and ranching.

The project is located away from residential areas and would be visible along Kunia Road and from a distance. The project is not expected to impact cultural activities, archaeological or natural resources. We have had many meetings and discussions with community members about the Mahi Solar project and how it can support local agriculture in Kunia. If you would like to receive further information about the project or have thoughts, suggestions or questions, please sign up for our email list.

Site Map

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Project Location

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Project Schedule and Approvals

The following is an overview of the planned project schedule and a status list of the permits and approvals that will be required.

Anticipated Permit/Approvals:

Potential Impacts

The positive impacts from a solar project are more clean, locally generated renewable energy, less fossil-fuel burning, less greenhouse gasses that contribute to climate changes, and hopefully lower and/or more stable electricity prices. Because of the distance of the project from residential areas, most people who live in the general area will not see the project from their homes or experience any sound, visual or other impacts. The project is not expected to create significant impacts to archaeological resources, cultural practices, or any sensitive flora or fauna.

Portions of the project will be visible along Kunia Road and at a distance from certain viewpoints between Mililani and Honolulu. If the project moves forward, during the construction phase, there would be some additional vehicles on Kunia Road and some dust, but likely similar to what is now produced during farming in the same area. We have talked with members of the communities near the project site to share information about potential impacts – positive and negative – and received their input and suggestions about how to improve the project for everyone.

Based on studies, the project is not expected to create significant impacts to archaeological resources, cultural practices, or any sensitive flora or fauna. Longroad conducted an initial site assessment in 2017 which looked at archaeological, cultural, biological and other environmental resources, as well as potential impacts to drainage, traffic, view plan, and many other factors. The result was that the project will create minimal, if any, negative impacts to the on-site resources or the surrounding community.

To date, no sensitive resources or unique conditions have been identified that warrant special consideration in the siting process. Based on the land use and zoning designations, the proposed solar project is consistent with state and county land use regulations, and no changes in the land use classification or zoning district would be required for project implementation. The project received approval of its archaeological assessment from the State Historic Preservation Division and received approval of its Special Use Permit from the Honolulu DPP, Planning Commission and from the State Land Use Commission. Because of the delay due to the supply chain crisis, the project received approval to extend the dates in its Special Use Permit and will be requesting a similar modification of its Conditional Use Permit.

Community Engagement

Longroad is a strong proponent of community Engagement and is committed to sharing information about our planned energy projects and seeking community input that reflects the neighboring community voice, insight into cultural and environmental impacts and feedback on benefits and challenges. For the Mahi Solar project, we met and talked with people who live, work or spend time around the project site, or who are stakeholders in other ways, such as having family history in the area or other kuleana in or around the location.

Mahi Solar has provided, and will continue to provide neighboring community stakeholders with timely information during all phases of the project, during development, construction and operation of the project. Engagement discussions include:

• Sharing information about the plans for the project, including location, design plans and other features,
• Asking for ideas and input that could help improve the project and community benefits,
• Identifying concerns about the project and discuss ways to solve or mitigate any issues, and
• Providing a point of contact in Longroad and ways for community members to stay informed.

Longroad began the process of community outreach regarding the Mahi project in 2017. We contacted and spoke with many people in and around the greater Kunia area, which we consider the “host community,” including individual residents, farmers, organizations, businesses, kupuna, cultural practitioners, community leaders and government officials. We also conducted public meetings online and community meetings at Kunia Village and Kunia Loa Ridge Farmlands. We also identified other people who could provide feedback and suggestions about history, impacts to the landscape and cultural significance. Some of Longroad’s community outreach efforts focus on Native Hawaiian culture, including conducting initial community outreach and engagement with identifiable loea (practitioners), kumu (cultural teachers) or kupuʻāina (individuals with genealogical ties to the area) as a means to introduce the project as a concept and to seek to understand the perspectives, beliefs, and range of opportunities and concerns that these individuals may have regarding the project area and its historical/cultural context; its resources; and/or the nature of the project’s perceived impact on those elements.

Overall community reaction to this project has been mostly positive or neutral. The majority of community members’ comments have expressed support or acceptance about renewable energy generally and an understanding that renewables will replace fuel-based generation over time. Very few community members expressed concerns about the Project, either through more critical questions or occasionally stating their opposition to the proposed project. Compared to other projects that the Longroad team has developed in Hawai‘i, the Mahi Solar project has received the fewest negative comments or concerns so far.

The project was postponed in 2022 due to the global supply chain crisis, then was again selected in HECO subsequent RFP in 2024. We notified community members, held a virtual meeting for all interested stakeholders, and have continued to be in contact with community contacts through periodic phone and email contacts.

Project Update – February 2026

The Mahi Solar project executed a PPA with Hawaiian Electric in November 2025, which has been submitted to the Public Utilities Commission (PUC) for review and approval.

The project is completing its engineering and will submit a request for a modification of our existing Conditional Use Permit, followed by Grading and Building Permits.

If approvals are granted in time, we plan to secure construction financing and begin building the project in late 2026 and reach commercial operation in late 2028.

Prior to the start of construction, we will provide community updates regarding traffic and other potential impacts. People should expect a temporary increase in construction vehicle traffic on Kunia Road, as well as some additional noise and dust in the nearby area during the construction period.

Once the project is completed and operating, we will maintain an ongoing communication channel throughout operations, to receive and share info with community through this webpage.

Community Benefits

In addition to generating and storing clean, solar energy for the Oahu grid, Mahi Solar will also provide additional benefits to the local community. The Mahi Solar team had many conversations with community members and stakeholders about what kind of benefits would be most appropriate and beneficial to the surrounding community. The overwhelming consensus was that Kunia has long been an agricultural area, with much of the land being used for farming and many agricultural workers and their families residing there, so the Project’s community benefits should focus on supporting agriculture and farmers in the Kunia area.

So far, Longroad has already made contributions the Hawai‘i Agriculture Foundation) and the Agricultural Leadership Foundation of Hawai‘i, as well as a 3-year investment in an Agrivoltaic research program by the Hawai‘i Agriculture Research Center (HARC) to study what types of crops can be successfully farmed under solar panels in Hawai‘i. Thanks to Longroad’s initiative, HARC’s Agrivoltaic research is now also co-funded by other solar developers, in the interest of sharing results with the solar and agricultural industries and finding new ways to use our limited land for both agriculture and renewable energy. It is possible that Mahi Solar will be the largest agrivoltaic project in the United States, combining both commercial solar and commercial farming, and potentially developing new opportunities for sustainable, local food production.

Once the project is completed, Mahi Solar will provide community benefits worth approximately $500,000 per year, for the 25-year life of the project. We have been working with many stakeholders to develop a community benefits package that details where and how those funds will be spent, and what written commitments or agreements will be included to ensure that funding continues during the life of the project. The final details of the community benefits are still being determined with the recipients, but the benefits that are under consideration include:

• Dedicating 4 acres of land for agriculture infrastructure to support farming (no solar construction);
• Providing a potable water washing facility for local farmers to wash produce;
• Providing a electrical connection for local farmers to access power;
• Purchasing solar-friendly farming equipment that can be shared by local farmers;
• Funding an Agrivoltaic Resource Expert to support local farmers and ranchers who want to begin commercial agrivoltaic farming at area solar projects;
• Funding HARC to continue agrivoltaic research and develop resources to share with local farmers;
• Funding local organizations that support local farming and agriculture, such as Hawaii Agriculture Foundation, Farm Link Hawaii, Go Farms, Hawaii Farm Bureau, Hawaii Agriculture Leadership Foundation.

Once the Mahi Solar project is completed, the final details of the community benefits package will be posted publicly on this webpage and provided to Hawaiian Electric for its own reporting.

Contact:

Please feel free to contact us about the Mahi Solar project at any time.
Email: mahisolar@longroadenergy.com