City of Sebastopol - Mandatory Solar Requirement for Residential and Commercial Buildings

In 2013 The City of Sebastopol became the second U.S. city to require photovoltaics (PV) to be installed on new buildings. The ordinance applies to all new commercial and residential buildings, and additions to existing commercial and residential buildings. The ordinance defines additions to commercial buildings as any addition that increases the square footage by 1,800 or greater and all remodels, alterations or repairs of more than 50% of the structure. The ordinance defines additions to residential buildings as any addition that increases the square footage by 75% or greater and all remodels, alterations or repairs of more than 75% of the structure.

Requirement

Minimum system size may be calculated by either of two methods, prescriptive or performance. Buildings using the prescriptive method must install 2 watts per square foot of conditioned building area including existing, remodeled and new conditioned space. Buildings using the performance method must use modeling software or other methods approved by the official to demonstrate that the system installed will meet 75% of the building's annual electricity load.