HI SB665

Replaces the renewable energy technology systems tax credit with separate tax credits for solar energy property, wind energy property, and energy storage property, with credit percentages declining from 25% to 15% between 2018 and 2024.

Establishes tiered credit caps based on property type: $2,250-$5,000 for single-family residential solar, $350-$700 per unit for multi-family residential, and up to $500,000 for commercial properties.

Creates new provisions for energy storage systems and combined solar-storage systems to receive dedicated tax credits of 25%, 20%, or 15% depending on installation dates, with caps ranging from $5,000 to $500,000.

Directs the Department of Transportation to identify a state land site and construct or renovate a building to achieve net zero emissions as a demonstration project, with cost-benefit analysis due to legislature by 2020.

Eliminates tax credits for renewable energy systems required under section 196-6.5 on newly constructed single-family homes and sunsets all renewable energy tax credits after December 31, 2035.