2011 Energy Report

This summarizes our energy production and consumption for calendar year 2011.


Solar electricity produced: 6033 kW h (16.5 kW h per day)
Electricity consumed: 6150 kW h (16.8 kW h per day)
        Non-heating: 5350 kW h,  heating: 800 kW h
Net electricity deficit: 117 kW h (-2%)


Our first 12-month report started April 1 2010 when we first activated the PV system and went through April 1 2011, but this report covers calendar year 2011 so there are a few months of overlap. For calendar year 2011 we fell just short of our goal to produce more electricity than we consumed, with a net deficit of 117 kW h for the year. Compared to our first 12 months of operation, average daily production dropped by 0.3 kW h but consumption increased 1.8 kW h. Some of that is due to having an additional family member living here since mid-year, and some is due to adding an upright freezer that uses about 1 kW / day.

Below is a graph showing the inside (red) and outside (blue) temperatures that we recorded throughout the year. Overall the house was very comfortable, with just a few days in the upper 70s during some hot summer weather when allergies made us reluctant to open up the house at night since our ventilation system filters out pollen from the incoming air.

The graph below shows the heat storage tank temperatures over the year. The big gap is when we drained the tank due to a leak, and we were able to get the tank warmed up again in the fall but not to the degree we would have liked.



This page was updated on Wednesday January 11, 2017