Here's two graphs for July through December, showing our usage vs. PV production, and where the energy is going. In the first graph, one can see the usage increasing as we begin to use the heat pump at the end of October, and the solar electricity is dropping off as the days get shorter and cloudier. In December we go from being a net energy exporter to a net energy importer. Only by installing the woodstove will we be able to be energy exporters each month, which is my goal. Our shortfall of 183 kWh in December is caused by the 238 kWh the heat pump consumed.
In the graph below the energy usage is broken down by end use. Other includes the composter exhaust fan, lights, wireless router and modem, computers, and small kitchen appliances, as well as any power tool usage. I'm a bit confused why there are peaks in Other in August and October. Oh wait, in August we had an influx of guests, which also shows in the DHW energy usage. Maybe on MV that month should be AuGuest :-) October, that's still a mystery... One can also see the increase in cooking energy in November and December. Less fresh food straight from the garden, plus holiday cooking and baking, are the reasons. R/F are the refrigerator and the chest freezer, and the change in their energy consumption is addressed in this post.
I think we have a strong chance to achieve net zero for our first year. The utility meter read 100,137 kWh when the PVs came on line in early June, and it read 98,448 this morning. Since June 9th the PV system has generated 1,689 kWh more than we've consumed. I can imagine our January and February usage cutting that surplus in half, yet sometime in March I expect we'll get back to net exporting. Stay tuned...