Heat map of high temps in July
Heat map of high temps in July

We generated 970 kWh in July, up 3% from last month. That is our best month yet, but in line with last month’s daily average of 31.3 kWh. We used 319 kWh, 5% less per day on average than last month. We turned on the air conditioning for 3 days during a particularly humid run, and periodically for a few days the next week. We used 12 kWh for cooling / dehumidification, 8% of our month’s total usage. We generated a 651 kWh surplus this month, our 5th surplus month in a row and highest yet.

All values in kWh (except HDD).

  1. January values based on meter reads.
  2. February values based on TED data.
  3. Heating Degree Days (a measure of how many outside degrees in a day it is below a target inside temperature)
  4. Calculated from our HOBO outdoor weather monitor hourly data, unless otherwise noted.
  5. January HDD data downloaded from degreedays.net, Station ID: KALB (Albany International Airport).
  6. March values based on meter reads. (TED died March 1st, eMonitor installed March 16, 2012)
  7. Values based on eMonitor data.
Jan 1 Feb 2 Mar 6 Apr 7 May Jun Jul
Solar PV production 369 597 860 925 867 939 970
Usage 873 666 515 378 309 325 319
Net usage or (surplus) 504 69 (345) (538) (558) (614) (651)
Avg. daily usage 28.2 23.0 16.6 12.9 10.0 10.8 10.3
HDD 3,4 1,212 5 1,045 704 617 298 144 34

I also did some number crunching this month to start tracking the efficiency of our water pump over time. We track the water pump electrical usage and the number of gallons of cold and hot water we use each month. We’re currently using 2.6-2.7 watt hours per gallon of water pumped from the well. That’s roughly 374 gallons per kWh. I’m curious if that is a good number or not? I’ll have to do some research.

The image at the top of the post shows a heat map of the high temps of the month. The average temperature in July was 73.6F, up 7F from June. You can see heat maps and detailed charts of temperature and electrical usage at netplusdesign.com. View solar, usage, net usage, temperatures and HDD for all of February and circuit-level data for 16 days in March and the full months of April through July.