Added 3 kw to my 4.6 kw PV system

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georgepds

Minister of Fire
Nov 25, 2012
878
The building inspector signed off on the permit.

The new system is under SREC 2, so I had to put in a separate monitoring system ( shown upper left). The enphase tracks both (center) , and the old solarenview (SREC 1) tracks the roof (lower right). Massachusetts requires a meter based monitoring system , and the ordinary enphase just does not cut it.

The roof has 4.6 kW and the shed 3.05 kW, so I expect the shed to produce about 2/3 of the roof. On last Thursday that’s what it did: roof 30 kWh, shed 21.2 kWh. The shed panels are a “ground rack” and cooled from all sides. If you look close you see that they got 6.95 equivalent hours of full sun (not bad)

Now that I’m power rich I’ve started heating more with the heat pump. The heat pump , a Fujitsu 12k RLS2H, is a little small to do in the dead of winter ( 12k BTU /hr) so I’ll have to buy a second one for upstairs.

I did a projection of how much power I can expect. I took the numbers from the roof from 3/16 to 2/17 and bucked them up by 2/3 . On a year basis I did 6,425 kwh, to which I estimate another 4,284 kwh which will give 10,709 kwh.. enough to run the car, the house, and heat it too .

The excess energy from the shed panels is not enough to heat the house without a heat pump. The heat pump COP gives you a factor of 3 , so that 4.3 MWh becomes 12.8 MWh of heat delivered to the house. I use about 2 chords. Estimating at 5 MWh per chord means I use about 10 MWh per year in heat.. so that 12.8 MWh should be about right (or just a little more)


date roof shed total
Mar-16 512 341 854
Apr-16 647 431 1079
May-16 736 490 1226
Jun-16 808 539 1347
Jul-16 745 496 1241
Aug-16 720 480 1199
Sep-16 497 331 829
Oct-16 354 236 590
Nov-16 406 271 677
Dec-16 319 213 532
Jan-17 310 207 517
Feb-17 372 248 620

Total 6425 4284 10709


3-23 energy .png
 
Very jealous. Where did you get them from? Do you use batteries for storage? Are you off grid?
 
Hi

The new panels are LG 305 all black, the microinverters are enphase s280. I built the rack on the shed. A company called Sunlight solar sold me/put up the panels and pulled the permits.

No batteries, all grid tied

--G