Commercial solar is a 30-year asset, but what does it really deliver after more than 10 years? When does energy production start to decline?
We can show you how it adds up on paper, but reality doesn’t always follow the same trajectory as initial expectations. We tracked down one of Artisun Solar’s clients who have been producing solar continuously for more than a decade.
What you’re about to see isn’t a model or projection. You’re going to see real-world production data and energy value from a solar system installed in 2014.
Understanding Solar Degradation
Like any long-term investment, solar comes with expectations of degradation, a slow decline in performance over time.
This isn’t unique to solar equipment.
Your car’s gas mileage doesn’t stay the same after ten years on the road, and your phone’s battery doesn’t hold a charge like it used to after just a few years.
Solar is no different…on paper.
Most commercial solar proposals, ours included, feature an estimated degradation rate, meaning you’d expect an average loss in energy production annually as the system ages. Typically you’ll see a degradation rate between 0.3% and 0.6%.
What this means: If you see a degradation rate of 0.35%, you would expect a 3.5% loss in energy production after 10 years.
Now that we know what to expect, let’s see what the real world scenario looks like. Let’s look at energy production data from Souder & Sons to find out.
Souder & Sons: 10 Years Later
In 2014, Souder & Sons were constructing a new 2500-head wean-to-finish hog barn. Even if you aren’t familiar with agriculture, this is a building that’s going to use a lot of electricity.
LED variable lighting was added throughout the building to reduce the overall energy usage, and solar was a natural fit to reduce power costs as much as possible.
Their solar array was energized in October 2014, which is when it started to produce electricity.
Measuring Solar Performance at Souder & Sons
Here’s how it’s going at Souder and Sons: in 2024, the solar array produced more energy than it did in 2015. Check out the chart below for annual energy production data:
“Solar holds up surprisingly well,” said Souder & Sons President Chuck Souder. “I thought there may be [solar] cell efficiency degradation and dirty panels developing over time, but electrical generation has been very steady the past 10 years.”
Year-to-year fluctuation as this chart shows is typical and largely unrelated to degradation.
Solar performs best in sunny conditions but can still produce in cloudy weather. Precipitation, such as rain and snow, directly impact energy production. Even severe weather such as hail hasn’t damaged the solar panels at Souder & Sons.
As Chuck explained: “Structurally, snow loads, wind, hail, and rain have not damaged the panels. We’ve only had to replace one inverter, luckily just a couple of months before the 10-year warranty expired. I thought there may need to be more parts replaced over time. Otherwise, it’s been a maintenance-free system.”
The system is doing exactly what it was built and designed to do with little maintenance required.
Financial Impact of Solar Power: Energy Value
To put this into perspective, the value solar has provided Souder & Sons is substantial. Energy Value is based on the utility bill savings as well as avoided cost reimbursement through the power company:
The avoided cost reimbursement is what the utility company, which is Heartland Power Co-Op for Souder & Sons, pays for the electricity sent back into the grid.
“Altogether, considering solar power used in the barn plus Avoided Cost reimbursement from [Renewable Energy Credits], cost of power for the barn has been reduced by 57.7% so far this year,” Chuck said in August 2025.
Annually, Souder & Sons is saving around $4,700 in utility bills. With at least 20 years left in its lifespan, their system is on track to save more than $140,000 in electric costs alone.
The Bottom Line: Solar Performs for the Long Haul
After a decade in operation, the solar array at Souder & Sons demonstrates what commercial solar is truly capable of: long-term, reliable energy production that consistently delivers financial value.
Despite typical expectations for degradation, the system continues to perform at or above its original projections with minimal maintenance.
Solar is a 30-year asset, and solar arrays that are designed by commercial solar experts like Artisun Solar show the longevity and potential of solar on any commercial building, from agriculture to manufacturing.
If you’re wondering what solar can do for your business today, tomorrow, and 10+ years down the line, let’s talk. Start here for your free solar analysis.
Solar Glossary
- AC (Alternating Current): The standard form of electricity used in commercial buildings. Converted from DC by a solar inverter to power lighting, equipment, HVAC systems, and more.
- Avoided Cost Reimbursement: A credit from the utility for excess solar power sent to the grid, based on the utility’s wholesale cost of generating or purchasing that electricity.
- DC (Direct Current): The type of electricity solar panels naturally generate. It must be converted into AC to be used in commercial facilities.
- Degradation Rate: The annual percentage decrease in solar panel output due to age or environmental exposure. Most commercial panels degrade at just 0.3%–0.5% per year.
- Energized (Commissioned): The date a solar system is officially activated and begins producing electricity. Often referred to as the “go-live” date.
- Energy Value: While energy savings is the money you didn’t spend on utility bills after going solar, energy value is broader. It’s the total financial benefit a solar system delivers, including reduced utility bills, avoided-cost credits from the power company, protection against rising rates, and the stability of predictable energy expenses.
- kWh (Kilowatt-Hour): A unit of energy that measures how much electricity is used or generated over time. One kWh equals the energy consumed by a 1,000-watt appliance running for one hour.
- Production Variability: Normal year-to-year fluctuations in energy production caused by changes in weather, snowfall, or cloud cover. These variances don’t typically affect long-term solar performance.
- Photovoltaic (PV): A technology that converts sunlight directly into electricity using solar cells in a ground- or rooftop-mounted system.
- Solar Array: A group of solar panels connected together to generate electricity. In commercial settings, arrays are typically mounted on rooftops or installed on the ground.
- Trapezoidal: A type of roofing commonly seen in agricultural buildings, such as a hog barn. It’s a good candidate for a roof-mounted solar array, such a Souder & Sons.
Solar Degradation FAQs
- What is solar panel degradation?
Solar panel degradation is the normal, minimal decline in energy production over many years. - How much do solar panels typically degrade each year?
Solar panels usually degrade at a very low rate of about 0.3% annually, ensuring consistent and reliable energy production for decades. - Does degradation significantly impact solar savings?
No. Even with minimal degradation, commercial solar systems deliver substantial energy savings throughout their 30-year lifespan. - How long do solar panels maintain strong performance?
With quality panels and professional installation, solar arrays commonly maintain high efficiency and strong output for 30 years or more. - Are solar panels designed to withstand weather and environmental factors?
Absolutely. Commercial solar panels are built tough to endure weather conditions like snow, rain, and heat, maintaining consistent energy production year after year.
