Hawaii Green Infrastructure Loan (GEMS)

The Hawaii Green Infrastructure Loan (GEMS) is a loan program tracked in the federal DSIRE database as one of Hawaii's solar policy levers. Eligibility is scoped to residential customers, with a stated benefit of Low-interest on-bill financing. The program does not carry a scheduled sunset in DSIRE, though appropriations and enabling legislation can still be revised year to year. Like every state-level incentive, it is designed to stack on top of the federal 30% Investment Tax Credit rather than replace it.

Layered onto Hawaii's underlying economics, this matters more than it might look in isolation. The state averages 5.9 kWh/m²/day of usable sunlight and residential rates of 38¢/kWh, producing an estimated 10,337 kWh/year and $3,928 in annual utility offset on a typical 6kW system costing $20,400. Without incentives that baseline already implies a 5.2-year simple payback — every dollar this loan program delivers compresses that payback further and improves 25-year net returns, currently modeled at roughly $77,800 before accounting for the Hawaii Green Infrastructure Loan (GEMS) itself.

This program is not the only option. Hawaii has 4 solar incentive programs indexed in DSIRE, including adjacent options like HI Solar Property Tax Exemption, Hawaii Smart Export Tariff (SET). The state's net metering policy is classified as partial, which governs how excess generation is credited and often determines whether a given program is worth claiming for a specific household. Before applying, verify current terms on the official program page, confirm your utility participates, and consult a qualified tax professional about how state credits interact with the federal ITC on your return.