B5.8 Solar-ready
Amend local development code to require solar-ready construction for all building types.
Installing solar photovoltaics on existing buildings is often difficult and cost-prohibitive. The roof space on older buildings is not designed with the addition of a PV system in mind, which can require extensive retrofit and restructuring of the roof to accommodate a PV system. Designing and constructing new buildings to be solar-ready is a cost-effective strategy to lowering solar installation costs, which increases payback time and the general financial benefits of a solar PV system.
Appendix N to the State energy code already has solar readiness provisions for non-residential buildings five stories or less – but it doesn’t take effect unless jurisdictions explicitly adopt it. Lacey and Tumwater have done this.
The 2015 Seattle Energy Code requires new commercial buildings and multi-family above three stories to have a renewable energy system of at least 70 watts for every 1000 square feet and/or a solar-ready roof, depending on the building’s size and type. The first requirement is intended to make solar energy a standard part of construction in Seattle, and the second ensures that expanding the installation installation of future larger-scale solar will be straightforward and economical when it becomes competitive with grid power. (The code also provides several alternative ways to meet the renewable energy requirement.)
Energy Trust of Oregon, through the Solar Ready Initiative, offers an incentive of up to $15,000 and technical assistance for new commercial construction built to ETO’s solar-ready standards.
The 2018 International Residential Code Appendix T (formerly Appendix U in the 2015 IRC) and the 2018 International Energy Conservation Code Appendix RA contain solar-ready provision for “new construction where solar-ready provisions are adopted.” Examples of Cities adopting the Appendices include El Paso, Denver, and most recently St. Louis, MO, which requires all new residential and commercial buildings to be solar-ready.
The 2019 California Building Energy Efficiency Standards, which took effect on January 1, 2020, require solar photovoltaics systems on all newly constructed single-family and low-rise multifamily residential buildings. Newly constructed non-residential buildings, which include hotels/motels and high-rise multifamily, are required to design solar-ready rooftops.