You open the Equinox app, the numbers load fine, and something looks off. Yesterday’s total is lower than you remember, this month trails last summer, or the figure just does not match the savings you were promised. If your SunPower is producing less than expected, the first question is not “how do I fix it” but “is anything actually wrong?” Most of the time, the answer is no, because solar output swings with the season, the weather, and the age of the panels. But some shortfalls are real, and catching those early protects both your bill and any warranty claim you are owed. This guide shows how to tell the difference and what to do about each case.
First, Rule Out an App or Reporting Glitch
Before you treat a low number as a production problem, make sure the number itself is trustworthy. Monitoring data commonly lags real-time by 15 minutes to a few hours, so a daily graph that seems to flatten in the afternoon has often just not caught up yet. Check again in the evening or the next morning before drawing any conclusion.
If the app is frozen, showing a blank graph, or reporting the system offline entirely, that is a reporting fault rather than a production fault, and your panels may well be making full power while the app shows nothing. When the monitoring app itself is stuck or offline, work through those fixes first, then come back to judging output once the data is flowing again. Everything below assumes the app is working and the figures it shows are current.
What Normal SunPower Production Looks Like
A healthy system does not make the same amount of power every day, and the variation is wide enough to alarm anyone who expects a flat line.
Daily and seasonal swings are the biggest factor
Output tracks the sun, so it rises through the morning, peaks near midday, and falls to zero at night. Across the year, the difference is larger still. A California system routinely makes two to three times as much in June as it does in December, purely because summer days are longer and the sun sits higher. A winter reading that looks alarming next to your July peak is usually just winter. The honest comparison is this December against last December, not this December against last July.
Slow degradation is expected, not a defect
Solar panels lose a small amount of output as they age, typically a fraction of a percent per year for high-efficiency hardware. Over a decade that adds up to a modest, gradual decline, not a sudden drop. SunPower’s premium panels are built to degrade slowly, and you can see how SunPower’s high-efficiency panels are built in the full system review. A slow, steady fade of a few percent over many years is the system behaving exactly as designed. A sharp drop from one month to the next is the pattern worth investigating.
Everyday Reasons Your Numbers Look Low
Once you have accounted for season and age, most remaining shortfalls trace to a handful of ordinary causes you can check yourself.
Shading and soiling
Anything that puts your panels in shadow cuts output, and shade grows over time. A tree that was trimmed three years ago, a new second story next door, or a rooftop vent added during a remodel can all clip your afternoon production. Dust, pollen, and bird droppings do the same on a smaller scale. In much of California, a long dry summer leaves a visible film that the first good rain washes off, at which point output ticks back up. If a dusty hillside or farm sits near you, a gentle rinse can recover a surprising slice of lost production.
Weather, smoke, and heat
Cloud cover obviously lowers output, but two California factors catch people out. Wildfire smoke can dim a whole region for days, dropping production well below a clear-sky day even when the sky just looks hazy. And extreme heat slightly reduces panel efficiency, so a blistering afternoon can read a touch lower than a mild, bright one. None of these are faults, and they resolve on their own when conditions change.
A recent change at home
If your bill went up but production held steady, the panels may be fine, and your usage simply grew. A new EV charger, a heat pump, a pool pump, or a home office running all day raises consumption without touching production. The app shows both, so compare the two before blaming the panels.
How to Check Output Against What the System Should Make
To move from “feels low” to “is low,” use a couple of concrete comparisons.
Compare the same month year over year
Pull up the same month from last year and the year before in the app’s history view. A drop of a percent or two year over year is normal degradation. A drop of 20 or 30 percent against the same month last year, with similar weather, is a genuine red flag that warrants a closer look.
Watch for a single panel or string sitting at zero
Panel-level monitoring is the most useful thing the Equinox app offers here. If one panel or one section reads zero or far below its neighbors for days on end while the rest report normally, that points to a specific hardware fault, a failed microinverter, or a bad connection, rather than a system-wide dip. A whole system that is proportionally low points more toward shading, soiling, or weather. One dead panel among healthy ones points to a service call.
When It Is a Genuine Fault
If you have compared year over year, ruled out shade and soiling, and confirmed the data is current, a large and lasting shortfall is worth escalating, especially a panel or section stuck at zero or a sudden double-digit drop that never recovers. Those symptoms suggest failed hardware, and hardware is exactly what a manufacturer or workmanship warranty is meant to cover.
Coverage is where the 2024 corporate history matters. The original SunPower Corporation filed for bankruptcy in 2024, and legacy systems installed before late 2024 lost the backing of that original installer. The brand and its warranty support have since been run by a separate company, the current SunPower, which has operated since 2025 and is not the bankrupt predecessor. Which entity stands behind your panels depends on when and by whom they were installed, so before you assume you are on your own, check what your warranty covers after the 2024 transition. Many production faults on qualifying systems are still covered.
Why a Production Shortfall Costs More Now
It is tempting to ignore a small dip, but under current California rules, a shortfall is more expensive than it used to be. Since California’s NEM 3.0 rules pay far less for power you export than for power you use on site, the value of your system now comes from covering your own daytime and battery-shifted usage. Every kilowatt-hour your panels fail to make is one you buy back from the utility at a retail rate that keeps climbing. A system quietly running 15 percent low hands that 15 percent to your utility every month, which is why it pays to catch and fix a real shortfall rather than live with it.
When the system is simply too small
Sometimes the panels are healthy, and the math still does not work, because your electricity needs have outgrown the array you installed years ago. If a new EV or an all-electric remodel has pushed your usage past what the system was sized for, the fix is not a repair but more capacity. In that case, consider adding a battery or expanding the system so your production keeps pace with what your home now draws.
Getting a Genuine Underperformer Serviced
If the diagnosis points to real hardware trouble, the practical hurdle is knowing who to call. Start by making sure your original installer is reachable, using this guide to confirm the company that installed your system is still operating. If that company has closed, a current SunPower dealer can usually service the equipment instead.
If the system is well into its second decade, repairs are stacking up, and degradation has stacked on top of a fault, replacing it may make more sense than patching it. Weigh whether it is time to replace an aging system against the cost of ongoing fixes, and review what a current SunPower system costs in California so you can compare a modern, higher-output array against the one slowly fading on your roof.
Turning a Low Number Into a Clear Answer
A production figure that looks low is a prompt to investigate, not a verdict. Check that the data is current, compare the same month year over year rather than against your summer peak, and rule out shade, soiling, smoke, and a recent jump in your own usage. What remains after that, a panel stuck at zero or a lasting double-digit drop, is a real fault worth a warranty check and a service call. If you have worked through these steps and still cannot tell whether your system is underperforming or simply weathering a California winter, contact the SunPower Estimate team for a straight read on what your numbers mean and what, if anything, your system needs.
Frequently Asked Questions
Why is my SunPower producing less than it used to?
Most often, the season, since a system makes far less in winter than in summer, or slow age-related degradation of a fraction of a percent per year, which is normal. Shading, a film of dust or pollen, wildfire smoke, and extreme heat also lower output temporarily. Compare the same month against last year, not against your summer peak. A drop of a percent or two is expected, while a sudden 20 to 30 percent decline against the same month last year points to a genuine fault worth investigating.
How much should my SunPower system produce?
There is no single number, because output depends on system size, roof orientation, shading, and the season. The best benchmark is your own history: pull up the same month from previous years in the app. A California system commonly makes two to three times more in summer than in winter, so judge each month against the same month last year, not against your best day ever.
Is low winter production a sign that my panels are failing?
Usually not. Shorter days and a lower sun angle mean every solar system makes much less in winter than in summer, and that seasonal dip is completely normal. It only warrants concern if this winter is far below the same month in previous years under similar weather, or if one panel or section reads zero while the rest report normally.
One of my panels is reading zero. What does that mean?
A single panel or section stuck at zero or far below its neighbors for days, while the rest of the array reports normally, usually indicates a specific hardware fault, such as a failed microinverter or a bad connection, rather than a system-wide issue. That is a service-call symptom. Note which panel and how long it has been down, then have it inspected, since a qualifying fault may be covered under warranty.
Does the 2024 SunPower bankruptcy affect a warranty claim for underperformance?
It can, depending on your system. Systems installed before late 2024 lost the backing of the original SunPower Corporation, which went bankrupt that year, while the brand and its warranty support have since been run by a separate current SunPower operating since 2025. Whether a production fault is covered depends on when and by whom your system was installed, so confirm your current coverage before assuming a repair is out of pocket.
