One of the most common complaints we hear from homeowners is that their electricity bills are still high because their new solar panels are not producing enough power. You were sold on a specific level of performance, and if your system isn’t meeting that promise, it’s a major problem. This guide will walk you through the essential steps to diagnose the issue and determine if you have a case for a dispute, whether the solar rep gave you too small of a system, or the system itself is faulty.
Step 1: Read Your Original Proposal & Contract
Go look through your old paperwork and find both the contract and hopefully the proposal (if they even gave you one). The sales proposal should have an “Estimated Annual Production” listed in kilowatt-hours (kWh). This number is the dream you were sold on the proposal. Now, go look at the contract. Is it the same? Is it different? What matters at the end of the day, is what’s on the contract, but if the proposal and contract are significantly different, you’re going to want to take note of that for later in case you want to take legal action. But for now, let’s rely on the contract itself.
Step 2: Gather Your Real-World Production Data
The promises made in your contract are only one half of the equation. To build a strong case, you need to compare those promises against the hard data of what your system is actually generating. Fortunately, this information is usually easy to find in a couple of key places.
Your first and best source is your system’s monitoring application. Nearly every modern solar installation comes with an app for your smartphone or a web portal. This could be from a company like Enphase (the Enlighten app), SolarEdge, or the specific app from your panel manufacturer. Log in to this application and look for a “Production” or “Energy” report. You should be able to view your system’s output by day, month, and year. For your analysis, you’ll want to find the total kilowatt-hours (kWh) produced over the last 12 months, or for as long as the system has been active.
If you can’t access your monitoring app, your monthly utility bill is another excellent source of data. Your bill should show a credit for the excess energy your system sent back to the grid, often listed under a “Net Metering” section. While this isn’t a direct measure of your total production (since you used some of the power yourself), a consistently low credit amount is a very strong indicator that your system is not performing as it should. Your goal here is to get a clear, data-backed number for your system’s actual production to compare against what you were promised.
Step 3: Compare The Promise vs. Reality (Accounting for Variables)
Now that you have the promised production number from your contract and the actual production data from your app or utility bills, you can compare them. However, a fair comparison requires understanding a few key variables. Simply seeing a lower number for one month doesn’t automatically mean your system is faulty.
Solar production is naturally cyclical. You will generate far more power in long, sunny summer months than you will in short, cloudy winter months. For this reason, comparing a single month like December against an “average” monthly production is not an accurate test. The most reliable comparison is year-over-year. Look at the total kilowatt-hours (kWh) promised for the first year and compare it to the total kWh your system actually produced in its first 12 months of operation.
Even over a full year, minor deviations can occur. It’s important to consider legitimate factors that can slightly reduce output, such as:
- Weather: Was it an unusually rainy or cloudy year compared to the historical averages used for your estimate?
- Soiling: Have your panels become significantly dirty with dust, pollen, or bird droppings? A layer of grime can modestly reduce performance.
- New Shading: Has a neighbor’s tree grown significantly since the installation, casting new shadows on your panels that weren’t there before?
While these factors can account for small dips in performance, a significant and persistent shortfall—for example, 15-20% or more below the annual estimate—is a major red flag. This level of underperformance typically points not to weather, but to more serious, systemic issues that may represent a breach of your contract. If your data shows this kind of major, undeniable gap, the next step is to understand the likely culprits.
Step 4: Common Causes of Serious Underperformance
If you’ve confirmed a significant and undeniable gap between the promised performance and the reality, it’s rarely due to a simple issue like a cloudy season. A major shortfall typically points to a more fundamental problem with the system’s hardware or the quality of the installation—issues for which the solar company is responsible. The most common culprits include:
- Faulty Inverters: The inverter (or microinverters) acts as the brain of your solar system, converting the DC power from the panels into the AC power your home uses. A single faulty or failing inverter can drastically reduce or even halt production from an entire section of your solar array.
- Incorrect Installation or Design: Rushing an installation can lead to costly mistakes. This can include improper wiring, panels installed at a suboptimal angle, or placing a portion of the array in a shaded area that was not accounted for in the original performance estimate.
- Defective Solar Panels: While rare, sometimes panels are simply defective from the factory and do not perform to their warranted specifications. Proving this requires a detailed analysis, but it constitutes a clear breach of the product warranty.
Step 5: Your System is Underperforming. What’s Your Next Move?
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Step 4: Common Causes of Serious Underperformance
If you’ve confirmed a significant and undeniable gap between the promised performance and the reality, it’s rarely due to a simple issue like a cloudy season. A major shortfall typically points to a more fundamental problem with the system’s hardware or the quality of the installation—issues for which the solar company is responsible. The most common culprits include for when solar panels are not producing enough power are:
- Faulty Inverters: The inverter (or microinverters) acts as the brain of your solar system, converting the DC power from the panels into the AC power your home uses. A single faulty or failing inverter can drastically reduce or even halt production from an entire section of your solar array.
- Incorrect Installation or Design: Rushing an installation can lead to costly mistakes. This can include improper wiring, panels installed at a suboptimal angle, or placing a portion of the array in a shaded area that was not accounted for in the original performance estimate.
- Defective Solar Panels: While rare, sometimes panels are simply defective from the factory and do not perform to their warranted specifications. Proving this requires a detailed analysis, but it constitutes a clear breach of the product warranty.
Step 5: Your System is Underperforming. What’s Your Next Move?
Identifying that you have a problem is the first half of the battle. The next challenge is proving why the system is underperforming and demonstrating that it constitutes a breach of your contract or warranty. Navigating this alone—arguing with installers and deciphering technical jargon—can be an overwhelming and frustrating task.
This is the point where self-research ends and expert analysis begins.
At SolarDispute.com, we specialize in this deep analysis. Before you spend any more time and energy fighting with your solar company, our team of industry experts performs a comprehensive review of your entire case. We analyze your production data, your contract’s performance guarantees, and your equipment specifications to build a detailed report. This report documents every issue and identifies the specific contractual violations and breaches of consumer protection law that form the foundation of your dispute.
If you are tired of getting the runaround and are ready for a clear, data-driven assessment of your situation, we are here to provide the professional leverage you need.