pv report (ps-h report) question

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i have a simulation (leed) i am responding to comments on & just noticed
in my ps-h report for my pv system that:

a) despite not changing anything in the pv setup from my last submittal, and
b) the horizontal columns to the right (last graphic) that sum the
operating hours not changing,
c) there is a rearrangement in operating hours allocation between the
30/40 run hours and 70/80 run hours columns where the vertical column
(hours within each part load) are slightly different but the differences
cancel each other out so the horizontal (total run hours) total remains
the same,
d) and there is a slight change in the ac output kwh generated while the
dc input kwh remains the same. see screen capture below (new run on
left, old run on right). new inverter ac output kwh is slightly higher.

this is a little bit of a puzzler as i did not change any of the inputs
for the pv i'm not sure where to begin to look to see what may be the
cause behind the changes. (i have checked the pv inputs from the
original submittal & they're the same for the inverter & panels).

there was no review comment regarding the inputs, or the reports
specifically, just that the reviewer didn't understand the way equest
subtracts the pv from each end-use on the electric meter it is assigned
to, so if i resubmit with a different pv ac output kwh this may raise a
flag as i'm sure the reviewer (and myself) would expect the amount of pv
generated to remain the same if it wasn't changed. heck, it's confusing
me & i'm the one who set it up.

any ideas what would cause a change in the pv ac output kwh where the dc
input kwh stays the same? it doesn't sound like a pv module or shading
concern. i have had some adjustments made to the hvac & lighting (some
slight increases, some slight decreases) but neither system would affect
the output of the inverter, right?

summary columns for load hours when operating, note the horizontal
totals (right column) are the same but the verticals differ starting at
column 4 to column 9).

Patrick J. O'Leary, Jr.'s picture
Joined: 2011-09-30
Reputation: 200