Diocese of Honolulu


The Catholic Diocese of Honolulu comprises the entire state of Hawaii and the unincorporated Hawaiian Islands, and has been an integral part of the community since the mid-1800’s. It includes sixty-six parishes and twenty-three mission churches ministering to 215,000 Catholics on six islands, with forty schools, social services and affordable housing programs throughout the Diocese.


Improvements were needed to replace aging infrastructure and lower energy costs for the parishes throughout the Catholic Diocese of Honolulu. In keeping with its leaders’ commitment to careful stewardship of the earth’s resources, the Diocese sought a renewable energy solution designed to transform parish buildings into high performance facilities that support their religious mission.


Trane competed for, and won, a Request for Qualifications (RFQ), issued by the Roman Catholic Church in the State of Hawaii, to be their partner for both energy service performance contracting and the implementation of renewable energies. As part of Phase 1 of the Renewable Energy Solution, the Trane team surveyed sixty-six sites, before identifying nine qualified parishes for implementation of renewable energy. Trane continues to work with all of the parishes on energy conservation and renewable energy solutions, which will be implemented in additional phases.

In this first phase of Renewable Energy, Trane collaborated with the Diocese and Sunforce Solutions International, a fully vetted and competitively selected third-party Power Purchase Agreement (PPA) investment broker, to developed plans to implement solar photovoltaic roof-mount and carport structure solutions. Performing as the Engineering, Procurement and Construction (EPC) Provider, Trane’s plans included purchasing photovoltaic (PV) panels for the initial nine locations and hiring subcontractors to install the panels. Scope included both photovoltaic EPC, as well as electrical code repairs, and requisite upgrades to the roofing under the panels and electrical service. Trane also provides overall system monitoring, and operations and maintenance services. This project is the first of many to help the Diocese meet their energy consumption and renewable energy objectives.

Eliminating capital outlay, management burden
Sunforce Solutions, in collaboration with Trane and the Diocese, developed the Power Purchase Agreement (PPA) that helps the Diocese meet its energy challenges, without any capital outlay or the burden of managing and maintaining the solar system. Under the PPA, the kilowatt hours produced by the solar system are purchased from Sunforce Solutions PPA investors. The PPA agreement allows the parishes to lock into low, fixed-escalation energy rates for the next twenty years, generating energy savings and insulating the parishes from future rate volatility. At the end of twenty years, the Diocese has the option to purchase the system or renew it at 75 percent of current utility rates, at five-year increments out to forty years.

Ensuring efficient performance
Under the PPA, the solar system is designed to withstand 120 mph winds and the Hawaiian environment. It is also insured against theft, wind and earthquake damage. Trane provides system monitoring and analytics to ensure the system is operating at peak efficiency through the twenty-year contract duration. Each array is carefully monitored to ensure system output meets expectations. System performance in both real-time and historic review is available from any internet connected browser. Alarms are automated and detailed datalogs are recorded to analyze long-term trends.


Collaborating with the Diocese of Honolulu, Trane is implementing solar solutions consisting of forty-one utility meters spread amongst nine parishes, served by both Hawaiian Electric Company (HECO) and Maui Electric Company, Ltd (MECO). Performance to date shows that Trane has exceeded both its Start-up / Commissioning Performance and ongoing Continuous Metering Guarantees.

Diocese leaders anticipate that the 1.15 MWp installation, which consists of both rooftop mounted systems and carport structures, will meet 80 percent of future electrical needs, significantly reducing energy costs. The efforts of the Diocese are helping the parishes become better environmental stewards, and allowing them to allocate more of their budget to support their religious mission to serve the community. Phase II of the renewable energy project is currently under development, as are additional energy conservation projects within the Diocese.

“We are pleased that these renewable solutions allow us to focus on careful stewardship of God’s resources, as well as providing state-of-the-art technology to reduce greenhouse gases and the parishes’ overall carbon footprint,” said Vince Vernay, facility services manager for the Diocese of Honolulu.

About Diocese of Honolulu

St. Theresa in Maui was one of nine parishes selected for Phase I of the Catholic Diocese of Honolulu’s renewable energy project.

The 1.15 MWp installation included both rooftop mounted systems and carport structures.