You wrote a big check for solar or a battery. Maybe $15,000, maybe
$40,000. The panels went on the roof, the boxes on the wall, the system
switched on, and someone tells you, “You’re all set.”

So here’s a fair question: how would you actually know if it’s
working?

Not “are the lights on” — of course they are, you’re still connected
to APS or SRP. We mean working the way it should be working. Producing
what it should, on a hot Tuesday in July, for a system your size, on
your roof.

Most homeowners can’t answer that. And it’s not their fault. Nobody
handed them a way to tell.

The
only signal most people have is the bill — and it’s a slow one

Think about how you’d find out something was wrong today. You’d
notice the electric bill crept up. Or you’d get to the annual true-up
with the utility and the number stung.

The trouble is the bill is a lagging indicator — and a noisy one at
that. Your usage and consumption change with the weather. Utility rates
change. A hot month looks a lot like an underproducing month from the
outside. A cooler month looks like the system might be fine. The reality
is by the time the bill tells you something’s wrong, you’ve usually lost
a full season of production you already paid for.

You spent thirty grand on a power plant on your roof, and the
dashboard you’re judging it by is a utility bill that shows up 30 days
after there’s an issue.

“Is this
good?” is a question nobody answers for you

Most modern systems today send data if connected to the internet. In
fact most send a monthly production report — a number of produced
kilowatt-hours, maybe a nice looking chart.

But a number with nothing to compare it to doesn’t mean much. Is 900
kWh in May good for your system? Depends on how many panels you have,
which way your roof faces, how much shade you get, and what the weather
did that month. Without that context, the report is just a number that’s
hard to feel good or bad about.

So most people do the reasonable thing: they glance at the app for
the first couple of weeks, then never open it again. The system fades
into the background, and they hope it’s fine.

In Arizona, “fine”
can quietly stop being fine

We’ve been doing this since 2008, and the things that go wrong here
are mostly predictable:

• Dust and pollen build up and shave output a little at a time — you
  never see the day it happens, you just make less.
• A single failed microinverter or optimizer can drag down production
  while the app still shows green.
• An inverter fault can knock the system partly or fully offline, and
  unless someone’s looking, it can sit that way for weeks.
• Monsoon heat stresses the electronics right when you need every
  kilowatt for the AC.
• Monitoring falls offline silently and no one knows.

None of these announce themselves. They show up as a number that’s a
little lower than it should be — exactly the kind of thing the hardware
notices and a busy homeowner doesn’t.

How to actually
tell if your system is healthy

You don’t have to stay in the dark. A few practical things you can
do:

1. Open the app once a month, on purpose. Compare this month to the
   same month last year, not to last month. Solar is seasonal — July should
   beat December.
2. Watch for a flat spot. If production drops and stays down for a week
   or more while the weather’s been clear, that’s worth a closer look.
3. Read your true-up, don’t just pay it. If you used to bank credits
   through the summer and suddenly you’re not, your production may have
   slipped.
4. Trust a real number over a feeling. “It seems fine” and “it’s
   producing what it should for its size and season” are not the same
   thing.

That last one is the catch. Telling the difference takes a benchmark
— a sense of what good looks like for a system like yours, on a roof
like yours, in this climate. That’s the part homeowners almost never
have.

When
it’s worth bringing in someone who does this all day

If your bill has crept up, or you just want to stop guessing, you
don’t have to figure it out alone.

A $129 diagnostic brings you a certified local tech who can review
your data remotely or come out to your system if needed. The way we work
it: we try to research and resolve it remotely first, and only send
someone to your roof if we have to — that way the tech already knows
what they’re walking into. It covers a remote read, and if we do come
out, the trip plus the first 30 minutes on site. They pull the real
production numbers, check the hardware — panels, inverter, battery if
you’ve got one — and tell you straight whether it’s working the way it
should be working, or quietly losing you power. Standard hourly after
the first 30 minutes on site, only if there’s real work to do.

We monitor and manage 500+ systems across Arizona, so we know what a
healthy Phoenix-area system should be doing in any given month. Most of
the production problems we find are fixable once somebody actually
looks.

SouthFace Solar & Electric has served metro Phoenix and the
Prescott Tri-City area since 2008. Locally owned, licensed, and happy to
work on systems we didn’t install. ROC #249187. 4.6 stars on Google.

Wondering if your system is really doing its job? Call 480-405-6105
or schedule a diagnostic — we’ll tell you what your roof is already
trying to.

This is the first post in a short series on reading your solar data and knowing whether your system is actually doing its job. More posts coming over the next few weeks.