April saw the return of weather normalcy. (12% less heating degree days than March but only 8% less than the 10 year average, 7% more sun). This partially resulted in 25% lower energy usage in April. We used 49 kWh just for space heating. We also installed a clothes line outside and used the clothes dryer less this month. Our daily average usage was down 22% from March. We generated a 538 kWh surplus in April, our second surplus month in a row.
| All values in kWh (except HDD) | Jan 20121 | Feb 20122 | Mar 20126 | Apr 20127 |
| Solar PV generation | 369 | 597 | 860 | 925 |
| Usage | 873 | 666 | 515 | 378 |
| Net usage or (generation) | 504 | 69 | (345) | (538) |
| Average daily usage | 28 | 23 | 17 | 13 |
| HDD (base temp 68F)3,4 | 1,2125 | 1,045 | 704 | 617 |
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 April values based on eMonitor data.
April marked our first full month of circuit level data monitoring. As the circuit usage chart above shows, the largest percentage of our energy goes toward producing hot water (152 kWh). The second largest load was all the unmonitored circuits including the refrigerator, coffee maker, ventilator and all lights and plug loads (123 kWh). The air-source heat pump came in 3rd (49 kWh). The clothes dryer and range almost tied (26 and 25 kWh respectively). We did lot of cooking around Easter. Now that we have our clothes line, our dryer energy usage should continue to go down.
All the data is available at netplusdesign.com. You can now view solar, usage, net usage, temperatures and HDD for all of February and circuit-level data for 16 days in March and the full month of April.
If you ever want a Nest let me know lol. We bought one only to find out it wouldn’t work with our hybrid HVAC system. Boo….sadness.
Great looking project, I look forward to reading more about it. I stumbled upon it. We’re doing something similar in Ohio but not quite to the level you are. We just got our EnergyStar 2.5 certificate today.
Chris, thanks for reading. I don’t think the Nest will work with our system either, so I guess we shall both remain Nest-less. Maybe someone over at Make will figure out how to reverse engineer the Nest and use it as an interface for an interactive art piece. Congrats on the house, enjoy your Garden Weasel.