Why is my solar system not producing?

Three different things can look like “not producing”: a dead monitoring connection, a normal shutdown during a grid outage, or a real equipment problem. Weather, shade and dirt can also lower output without any fault. Work out which one you have first, then leave testing and repairs to a qualified solar professional.^1,2,3

Is my solar output zero, stale or just low?

A blank or frozen graph isn’t the same as a zero. A zero isn’t the same as a drop on one part of the system. Write down the time, the weather and any alert on screen, because that detail helps the person diagnosing it. It can’t point to a failed part by itself.^1,4

Most grid-tied solar shuts down when the grid does. The National Laboratory of the Rockies (NLR) says grid-tied systems without specialized inverters and islanding controls will be unusable in an outage, because interconnection standards require such systems to disconnect. Panels on a sunny roof can sit idle while the power is out.² NLR also notes that the extreme weather behind big outages can destroy system components, so a system that stopped during an outage may deserve an inspection afterward.²

A battery doesn’t change that by itself. Backup needs equipment designed to run while separated from the grid, and a drained battery with weak sun can leave you without power too.^2,5 If outages are the worry, read what solar panels do in a power outage or the page on battery storage and backup configurations.

Could my monitoring be offline while the panels still work?

A monitoring system that drops off the internet is one of the most common solar issues, and the panels can keep producing through it. The New York City ownership guide says owners often misdiagnose it as an inverter failure because no live data shows. A brief internet outage or a changed router is the likelier cause.¹

Its tip is easy to copy. Check whether other internet-connected devices at the property are working. If they aren’t, the problem is the connection, and your internet provider is the call to make.¹ Don’t change inverter settings or touch electrical equipment to bring reporting back. Our guide on what to do when solar monitoring goes offline covers the common causes.

Here’s an example, with made-up details. A homeowner’s app goes quiet the day after the internet provider swaps the router. The timing gives a technician a communications lead to check first. It isn’t proof the inverter needs replacing, and the app’s last-updated time is worth saving either way.¹

The utility bill adds context, but exports aren’t production. A 2002 Department of Energy fact sheet explains the flow: your home uses what it needs, and only power it doesn’t use immediately goes to the grid. When household use climbs, exports can fall while the panels produce the same amount.⁶

Why did my production drop: weather, shade, dirt, inverter or grid?

Sunlight varies with location, time of day, season and weather. The Department of Energy says Denver gets nearly three times more solar energy in June than in December, and that atmospheric conditions can cut direct sunlight by 10 percent on clear, dry days and by 100 percent on thick, cloudy ones.⁷

A winter dip alone doesn’t mean the panels failed.

Compare full reporting periods from the same season, not yesterday against today. The ownership guide also says to check the weather before calling the installer.¹

The same guide lists what can pull output down for real: shade from tree growth or a new antenna, dust from a nearby construction site, a microinverter or optimizer failure, grid voltage or frequency out of range, and, rarely, panel failure.³ A national-laboratory maintenance guide pictures soiling traced to construction-site dust at about 5 percent loss, though that guide is written for larger plants.⁸

Write down what you see and leave the roof work to a professional.^8,3

An inverter converts the panels’ direct current into power the house can use, so its failure interrupts production. An inverter that shuts off because the grid went out of range can look like a fault in the app, so take any error code to your provider rather than guessing.³ For a string inverter, the guide says a failure usually stops every panel connected to it.⁹

What can I safely check without opening anything?

Read the app, check the utility’s outage information, and note changes around the property. If the inverter has an external display you can see from a safe spot, jot down any message. Keep covers closed, leave switches and breakers alone, and stay off the roof.^1,2,10

1. Capture the evidence. Screenshot the alert, the last-updated time and the last complete production period, with units and date range.
2. Note the grid and internet. Is there a utility outage, an internet failure or a recent router change?
3. Describe the pattern. Did everything stop, did output fall, or did one group change?
4. List recent events. Storms, nearby construction, roof work, earlier service. Use paperwork and photos you already have.
5. Send a plain service request. Include the equipment model from your paperwork or app, and ask what the provider needs to separate missing data from lost generation.

Resetting equipment or flipping switches to “see if it comes back” is the one thing to avoid. The list above is for observing, not repairing. Electrical tests, roof inspection and cleaning belong with qualified professionals, since NLR’s maintenance guide names roof falls, electrocution and arc flash among the hazards of PV work.¹⁰

When should I call, and who do I call first?

Call when production stays unexpectedly low, when the inverter isn’t producing in daylight with its switches on and the grid back, or when the same fault keeps returning. The ownership guide describes a “sustained and unexplained drop in production” or a high-priority inverter error code as the point to contact your solar company.^3,4

Start with your installer if the system is still under its workmanship warranty. The guide says that’s the default action in that period, and that the solar company will review your online monitoring at no cost then. After the workmanship warranty ends, it may still help to call, because a manufacturer typically pays a contractor to fix or replace a faulty optimizer or inverter that’s under its own warranty.³ Some problems can be diagnosed remotely and others need a site visit.^3,4

Smoke, fire or sparks are a different category. Call 911 and tell the dispatcher the property has a solar system. Southern Maryland Electric Cooperative (SMECO) tells the public to stay at least 10 feet from solar equipment, never touch a damaged system, and wait for first responders. It also notes that panels stay energized as long as the sun is shining.¹¹ If equipment looks damaged, the same advice applies: stay back and don’t touch it. The ownership guide lists ground faults among the conditions inverters report through error codes, so pass any such alert to your provider rather than clearing it with repeated resets.^3,11

What should a diagnosis include before any repair?

A good diagnosis answers one question: is the problem in reporting, in generation, or both? NLR’s maintenance guide calls it critical to identify the root cause of a failure before dispatching service providers, and says that takes either qualified people who understand the plant’s design or software that flags anomalies.¹²

That guide is written for large plants, so treat these four steps as questions to settle with your provider, not a fixed test package:

1. Review records. Share monitoring access through the provider’s approved process, along with equipment documents and past service records. Keep passwords private.
2. Find the cause. Is remote evidence enough, or does someone qualified need to inspect or test on site?
3. Define the repair. Get the finding, the evidence and the proposed work in writing. A symptom alone isn’t a reason to replace equipment.
4. Confirm the result. How will the provider check reporting and production after the work, under comparable conditions?

Limits apply. A whole-system total in the app can’t locate a weak equipment group, a communications outage can hide ongoing generation, and an outage stop can say nothing about damage. The diagnosis has to account for your design and the data available.^1,2,7

What are my next steps?

Treat the first day as evidence-gathering. If the app is stale, check the internet. If production is zero during a grid outage, wait for power to return before drawing conclusions. If output is low in good weather for weeks, call your installer or a service provider with your notes.

Soleil Energy services solar systems it didn’t install. Its monitoring and maintenance service covers fault diagnosis and repair for inverter faults, string failures and communication dropouts. A string is a connected group of solar panels. The guides on who services your solar panels and solar panel repair cover what to ask a provider.¹³

For unexplained production loss, request a system assessment or call (301) 953-4140.

This guide is general information, not legal, tax, or financial advice.

Sources (13)

1. Solar One for the New York City Department of Housing Preservation and Development, Solar Photovoltaic Systems: A Guide for Long-Term Ownership and Maintenance, May 2021, pages 15-16, https://www.nyc.gov/assets/hpd/downloads/pdfs/services/solar-pv-system-owners-guide.pdf; read October 25, 2026. General operating guidance for New York buildings; no New York policy is applied. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹

2. National Laboratory of the Rockies (published under its former name, National Renewable Energy Laboratory), Will Solar Panels Help When the Power Goes Out? Planning for PV Resilience, March 2020, https://www.nlr.gov/docs/fy20osti/75704.pdf; read October 25, 2026. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

3. Same source as ¹, pages 15-16. Causes of reduced output, inverter error codes, warranty and who to contact. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

4. Same source as ¹, pages 15-16. Persistent unexplained loss and remote versus site diagnosis. ↩ ↩² ↩³

5. U.S. Department of Energy, Solar and Resilience Basics, undated current page, https://www.energy.gov/cmei/systems/solar-and-resilience-basics; read October 25, 2026. ↩

6. U.S. Department of Energy, Connecting Your Solar Electric System to the Utility Grid, July 2002 fact sheet (document created September 2002), https://www1.eere.energy.gov/solar/pdfs/31687.pdf; read October 25, 2026. Used only for how electricity flows between home and grid, not billing rules or current rates. ↩

7. U.S. Department of Energy, Solar Radiation Basics, undated current page, https://www.energy.gov/cmei/systems/solar-radiation-basics; read October 25, 2026. ↩ ↩²

8. National Laboratory of the Rockies and partners, Best Practices for Operation and Maintenance of Photovoltaic and Energy Storage Systems, third edition, December 2018, section 5.7.1 and Figure 7 caption, https://www.nlr.gov/docs/fy19osti/73822.pdf; read October 25, 2026. Written for larger plants; used for the effect of soiling only. ↩ ↩² ↩³

9. Same source as ¹, page 17 (Inverter Failure). ↩

10. National Laboratory of the Rockies and partners, maintenance guide, December 2018, section 7 (Health and Safety), https://www.nlr.gov/docs/fy19osti/73822.pdf; read October 25, 2026. ↩ ↩²

11. Southern Maryland Electric Cooperative, Solar Panels (safety guidance), undated current page, https://www.smeco.coop/safety/solar-panels/; read October 25, 2026. SMECO serves southern Maryland; the safety guidance applies to solar equipment generally. ↩ ↩²

12. Same source as ⁸, section 8.1 (Qualifications of Plant Operators), December 2018. ↩

13. Soleil Energy, Monitoring & O&M, undated current service page, https://soleilenergycorp.com/renewable-energy/monitoring-and-om/; read October 25, 2026. ↩