The Building Energy sector is the second-largest source of emissions in the City of Cupertino. It is composed of emissions that come from powering the built environment—that is, the electricity, natural gas, and other sources of energy that power homes, businesses, and industrial sites throughout the City.

The majority of residents and businesses in Cupertino receive their electricity from Silicon Valley Clean Energy (SVCE)—a local utility company that is focused on generating electricity from entirely renewable and clean sources of energy. SVCE, together with decades of clean energy policy in the state of California, have driven down emissions from the Building Energy sector in Cupertino to be significantly lower than the equivalent sector for similar-sized cities around the country.

Yet more work remains to fully decarbonize this sector. Key initiatives include ensuring new buildings net-zero contributors to emissions, electrifying existing buildings which rely upon fossil fuels like natural gas, and decarbonizing the City's municipal operations by installing solar panels & promoting energy efficiency.