by Alan Pryor

On August 26th the Davis City Council passed a new ordinance setting minimum standards for Solar PV on new single family home construction.  The Davis Natural Resources Commission approved and forwarded to the Davis City Council a draft ordinance on April 28th.   This draft ordinance has been under development for over a year and included Staff’s analysis looking at requirements in other cities, solar at existing developments, discussions with staff and stakeholders, and general research.

The major provisions for the mandatory ordinance include:

• Tiered requirement for solar PV ranging from a 1.6 to 3.5 kW system on all new single-family homes based on house size as shown in Table 1.
• Accommodation for future expansion of the system.
• Provisions about process and submittal requirements.
• General standards for location and height.
• Flexibility for alternative compliance.
• Exemption provisions for tree preservation, roof limitations, and hardship conditions.

Table 1. Proposed Minimum Solar Photovoltaic Requirement per Residential Unit

Single-Family or Duplex                                                   Minimum System Size

1,000 sq. ft. or less                                                                         1.6 kW

1,001 – 1500 sq. ft                                                                          2.0 kW

1,501 – 2,000 sq. ft.                                                                      2.3 kW
2,001 sq. ft. – 2,500 sq. ft.                                                          2.5 kW
2,501 sq. ft. – 3,000 sq. ft.                                                          3.0 kW
More than 3,000 sq. ft.                                                                3.5 kW

The tiered approach is intended to provide certainty to developers about the requirements while scaling the system to house size. While other factors such as lifestyle and household size strongly influence energy use, staff believes that the linking the system size to the house size is a reasonable approach that is easy to understand and implement.

This ordinance reflects recent progress by new home developers in offering PV systems as standard features in new developments including the Cannery by New Home Construction, Shea Homes, and KB homes. The later two developers now offer not only PV on new homes as part of the new construction financing but also offer zero net energy home developments. It is clearly in the economic interest of new home buyers to take advantage of installed PV when purchasing a new home because it will result in net lower monthly outlays for energy and mortgage payments.

This ordinance also clearly reflects the goals of the City’s Climate Action Plan in lowering the carbon footprint.

Please thank the city council, city staff and members of the Natural Resources Commission for their work on this new ordinance.

City Council Email Addresses:
Dan Wolk dwolk@cityofdavis.org , Mayor
Rob Davis rdavis@cityofdavis.org , Mayor Pro Tempore
Lucas Frerichs lucasf@cityofdavis.org
Brett Lee blee@cityofdavis.org
Rochelle Swanson rswanson@cityofdavis.org

 Natural Resources Commission