We moved in on November 1st, 2013, and the PV system had been activated on October 20th. The NSTAR net meter read zero when installed, read 99980 (it goes down from zero if the energy is net exported) on Nov 8th 2013, and read 98852 on Nov 10th 2014, for a net energy export of 1,128 kWh in that year. The PV system made 6,198 kWh November through October, so we used 5,058 kWH for the year (these numbers are slightly off because of the non-simultaneity of the utility meter "year" and the fact that I read the PV meter on the 1st of each month). The monthly energy flow to and from the grid are shown in the graph below, assuming for simplicity that the NSTAR meter read zero on November 1st 2013.
Usage was a tad bit higher than I projected (somewhere around 4,700 kWh/year). One reason is the minisplit heat pump - it took me until early March to change the settings at the deeper levels of the controls that were enabling the unit to operate by cycling on at full speed then shutting down, repeatedly, working at its least efficient operating point. The subject of another post to be sure...
The eMonitor wasn't up and running until late January, so I don't have a full year's breakdown of where the energy is going, but I'd say the heat pump used almost 35% of the energy, the heat pump water heater just over 10%, and the fridge and chest freezer about 15%. The remaining 40% is cooking, water pumping (we planted several dozen trees and shrubs which we irrigated), lights, the HRV, and plug loads.
The net exported energy would power an electric vehicle for over 3,000 miles/year.
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