Monitoring Report of a ZNE Residence in Clovis, CA

As part of PG&E’s Zero Net Energy (ZNE) Pilot Program, De Young Properties designed and built a single story 2,064 square foot single family home located in Clovis, CA. It was built in 2013 and used as a model home until 2018 when it became occupied. All loads were monitored for the first year of occupancy; this report describes what was found.

Space heating represented the largest site energy end use category, at 40.4% of total household energy use. Plugs loads, cooling, and domestic hot water (DHW) represented the next largest energy end uses, at 15%, 13.3%, and 12.5% of total energy consumption, respectively.

Appliance energy use was dominated by the clothes dryer, accounting for 58.2% of appliance energy and 4.2% of total energy use. The electric circuit shared by the dishwasher, disposal, refrigerator, and kitchen plugs was the next largest appliance end use, at 25.3% of appliance energy consumption. Microwave and range share the same electric circuit and with the gas use of the range accounted for 13.2% of appliance energy use.

Total site energy consumption was 14,458 kWh-e, including 7,973 kWh of electricity consumption and 6,486 kWh-e of gas consumption. Total PV production was only 5,639 kWh. This is far lower than the expected annual production of approximately 9,300 kWh because of operational problems that caused the system to be offline for significant periods from late November 2018 through early April 2019 and then again in May 2019.

The ZNE definition used in the design of this house was based on site electricity consumption. While the actual PV system offset was only 70.7% of total site electricity, this was due to the solar system operational problems. If the solar system had been operational for the full year, the PV system offset of site electricity consumption would have been 116%, which would have met the ZNE performance goals of the design.