Solar part 3 (upgrade 2)

We have completed the 2nd upgrade to our power system.

Our original solar system has:

  • Longi Solar Half Cut Modules (14 x 375W = 5.25kW DC)
    • Degradation profile: < 2% first year,  0.55% years 2-25.
    • Efficiency: 19.5%
  • with Enphase IQ7+ Microinverters (14 x 295W = 4.130 kW AC)
Then we added batteries about a year ago:
  • Enphase IQ Battery 5P  (2 x 5kWh = 10 kWh)
Now we have topped up the solar system (in preparation for a future EV and to make us net positive in generation across the full year) with:
  • AIKO Solar Neostar 2S (12 × 510W = 6.12kW DC)
    • Degradation profile: < 1% first year,  0.35% years 2-30.
    • Efficiency: 23%
  • with Enphase IQ9 Microinverters (12 x 427W = 5.124kW AC)
  • Enphase IQ Battery 5P (2 x 5kWh = 10 kWh)
There are some technicalities in there including both the DC and AC sizing of the two solar arrays. The original panels are on the house roof and tilted 20° towards the sun, whereas the new panels are on the garage roof and tilted 7° away from the sun. This means that the garage roof panels are expected to underperform their specifications by ~ 15%. Both solar arrays are also challenged by the shading of trees.

At least in theory, we can produce ~ 9kW AC and have 20kWh of battery capacity. The additional panels and batteries were installed a couple of weeks ago (first week of June). This time around the software integration has been very smooth and we have been solidly producing more than we use since the new panels went in... even in the winter and even with a lot of overcast days. June sunny day solar production has been ~ 24kWh while our average consumption has been ~ 13kWh it well offset by our average production ~ 17kWh.

At this point we have no future upgrades planned until we install EV charging and go down that electric road.

In terms of how this impacts our power bills. Only time will tell, but given the current electricity market trends our export of electricity to the grid will more than cover any electricity import from the grid, but will probably not cover the increasing daily connection fee.

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