Solar Monitoring: Specific Features That Lower Your Solar OM Costs
Solar operations and maintenance (OM) costs can have a significant impact on the profitability of each project that an installer completes. According to Sunrun, operation accounts for 18% of solar system costs and according to National Renewable Energy Laboratory (NREL), OM costs can range from 18-28/kW/yr. This adds up considering the typical lifespan of the system is 25 years.
To put it into perspective, lifetime OM expenses for a residential system could be around 7 thousand assuming the site has an installation capacity of 10kW, and energy costs are 0.22/kWh. For a commercial system, lifetime OM expenses could be about 46 thousand assuming the site has an installation capacity of 100kW, and energy costs are 0.18/kWh.
There are many OM categories that range from system inspections, module cleaning, and component replacements, to list a few. While some of the operational costs associated with solar are unavoidable, they can be significantly reduced with module-level monitoring. The purpose of this blog is to show how module-level monitoring works and quantify the benefit it can have for installers and their customers.
Why monitoring is important
As mentioned, OM costs can be expensive especially when they start piling on year after year. According to Fixr, “the average cost of an annual inspection of your rooftop solar panels is typically 150 to 300.” If replacement or repair work is required, the costs could increase to 750 (see Figure 1 for examples). So, every truck roll that monitoring avoids, saves somewhere between 150 and 750.
How do monitoring platforms work?
Module-level monitoring is enabled by Module-Level Power Electronics, or MLPE. When an installer uses MLPE with monitoring capabilities with their installations, they get a digital view of the performance of each module on a mobile app or on a website.
For example, Tigo’s monitoring software called Energy Intelligence (EI) offers:
- Fleetwide management so installers can get complete visibility to all their installation sites in one place.
- System performance to get system updates about the inverter, batteries (if applicable), power meters, and more.
- See current or historical data down to the module-level.
Let use Tigo’s Energy Intelligence platform (which you can demo anytime) to show how can monitorization help installers save money.
Benefits of monitoring
Product disclaimer: The following benefits are specific to Tigo Energy Intelligence monitoring platform and our installers’ experience with it.
Minimize OM costs
With the app, installers can get system level, string level, and module-level visibility into the system and diagnose issues remotely, saving money with fewer truck rolls.
The longer a PV system is active and functioning, the more money both the system owner and installer saves. With monitoring capabilities through an app, installers gain visibility into each module of the system, making their job easier. Installers also get alerts when a performance or safety issue arises so the site can be quickly returned to normal.
Enhance the customer experience
System owners love having performance updates on their system to ensure their investment is working properly. With monitoring, installers can get visibility to all their sites from one spot with fleet, system, and module-level performance data. If the system owners are happy that their system is performing well under an installer’s management, they will be more likely to refer them to a friend.
Example 1: Homeowner calls for poor performance
An installer may get a phone call from a concerned homeowner on why their system has low performance with the assumption that some component is broken. Without monitoring, an installer would have to drive to the site to examine the system. Even if nothing needs to be done at the site, it can be a time intensive task to schedule, drive there, access the roof, and diagnose what’s going on. This is why truck rolls on average are so expensive.
With monitoring, installers can check an app and see what is causing the low performance from the palm of their hands. The poor performance could be due to shading instead of a broken component or could be due to numerous issues which the installer can learn in an instant. If we use the NREL data that was mentioned previously, avoiding this truck roll would save the installer on average about 225.
Example 2: Batching
If a truck roll is necessary, with fleet monitoring, installers can map out which sites need maintenance in a geography and batch the site visits. This saves installers time of not having to go back and forth and allows installers to tackle each system performance issue at once rather than accidentally missing a system failure which would require another truck roll.
Installers can also diagnose the issues before going on site allowing them to prepare necessary equipment to avoid extra trips back to the site. This round-trip time savings can save around 150.
Example 3: Failed Diode
Lots of system performance issues can go unnoticed without monitoring such as a failed diode. A failed diode could result in an energy production reduction of about a third of the panel. That could amount to 935 of production loss over 15 years, and over 25 years, that would be about 1,500.
For more detailed examples and explanations of real-life scenarios, check out this past webinar we made or read the webinar transcript here.
Monitoring is very crucial for installers to utilize in their solar projects to minimize OM costs and maximize profitability. Not only can it save installers thousands of dollars, but it can save them time allowing them to take on more customers adding to their overall revenues. The benefits of adding monitoring to system buildings greatly outweighs the costs of skipping out on monitoring and is an investment for installers to increase workflow to grow their business. Tigo Energy Intelligence enables fewer truck rolls, early detection, and customizable fleet-wide visibility to maximize the return on investment of installers’ solar projects. Allow monitoring to alleviate some stress – you won’t regret it.
To join in on discussions about solar or ask questions on solar, visit our Tigo Community page. To leave a comment on this blog, click here.
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Sunrun Solar Panels Review: Does Biggest Mean Best?
In 2021, Sunrun performed 13% of all residential solar panel installations in America. Should they put in your rooftop solar panels?
Andrew Blok has been an editor at CNET covering HVAC and home energy, with a FOCUS on solar, since October 2021. As an environmental journalist, he navigates the changing energy landscape to help people make Smart energy decisions. He’s a graduate of the Knight Center for Environmental Journalism at Michigan State and has written for several publications in the Great Lakes region, including Great Lakes Now and Environmental Health News, since 2019. You can find him in western Michigan watching birds.
- Lesser warranties for purchase
- Not upfront with pricing
- No price match guarantee
When it comes to residential solar panel installations, one company has put in more renewable energy than anyone else. In 2021, Sunrun captured about 13% of the residential solar market, according to a Wood Mackenzie analysis, about double the share of its two closest competitors, Titan Solar Power and Freedom Forever, combined. Sunrun’s place atop these market share rankings is thanks in large part to its 2020 acquisition of what was the second largest solar installer, Vivint. With the acquisition, the company has a footprint in 21 states, Washington, DC and Puerto Rico.
Most of Sunrun’s business is in solar leases. That means you can rent panels from it for a monthly fee, though it’ll sell you solar panels too. While there are dozens of solar panel providers and installers around the country (experts recommend getting multiple quotes), it’s worth looking at the major players. Sunrun provides strong offerings among the national players.
Sunrun’s warranties are top of the line if you’re going the route of power purchase agreement or lease. While it hasn’t named a new preferred panel after LG left the market, it’s looking to fill that space with tier one panels. They also offer strong battery options with Tesla’s Powerwall and LG’s RESU batteries.
Can solar panels save you money?
Interested in understanding the impact solar can have on your home? Enter some basic information below, and we’ll instantly provide a free estimate of your energy savings.
Sunrun, like most other solar providers, doesn’t give much pricing info up front. It also offers shorter warranties for customers who purchase panels rather than lease or enter a power purchase agreement. These points, and the fact that it doesn’t offer a price match, keep Sunrun’s score lower.
Below I’ll give you the essential information about Sunrun and, when it’s possible, let you know how it compares to the competition.
Can solar panels save you money?
Interested in understanding the impact solar can have on your home? Enter some basic information below, and we’ll instantly provide a free estimate of your energy savings.
What do I get from Sunrun?
Sunrun is different from the average solar company in the way it conducts business. Its bread and butter is solar-as-service. This means the vast majority of its customers (80 to 90%, according to a 2021 presentation to investors) lease panels for a monthly fee.
If you’re going to buy panels from Sunrun, you’re likely to get quality equipment. A Sunrun spokesperson confirmed the company uses multiple suppliers for solar equipment. Its preferred panel manufacturer, LG, stopped making solar panels in early 2022, so Sunrun is now working with their other module manufacturing partners to supply tier one panels, a spokesperson said. Tier one panels typically come from established companies with a long track record of quality. You should receive panels with high efficiency ratings and strong warranties. Likewise, Sunrun should be able to accommodate a preference for a specific panel.
Before you buy, make sure you read your purchase agreement and warranty. That’s especially important, because while Sunrun offers bumper-to-bumper coverage, maintenance and monitoring for its solar-as-service customers, those who purchase solar arrays from them are left to rely on manufacturers’ warranties. While 25 years is becoming more common, it’s still not ubiquitous. Sunrun also offers a 10-year workmanship warranty against damage to your roof or installation problems.
Sunrun offers Tesla Powerwall for whole-home backup and an LG Chem battery, which the company says can back up just the essentials, or four circuits (a circuit is everything connected to a breaker in your breaker box or electrical panel). Sunrun also offers battery storage to its solar-as-service customers through its program called Brightbox. Neither of the battery options are exclusive to Sunrun, so it shouldn’t be your deciding factor. Both battery options come with a 10-year manufacturer’s warranty.
Powerwall batteries can be installed indoors or outdoors. They’re about 6 inches deep, 2.5 feet wide and almost 4 feet tall, so they’ll fit most places. LG Chem batteries are a bit smaller, though they’re also deeper.
Powerwall holds 12.2 kilowatt hours of usable energy, while the LG Chem batteries offer 9.2 to 16kWh of usable energy, depending on the model. (LG Energy Solutions has recalled some of its batteries for a possible fire risk.)
It’s not clear which inverters Sunrun will use now that their preferred option, LG again, is no longer available. (Again, be sure to read your agreement and make sure you’re happy with the proposed equipment.)
Sunrun also has an app through which you can monitor your system’s production. Since I’m not a Sunrun customer, I wasn’t able to test it out. Some reviewers in Apple’s App Store and Google Play (the mySunrun app gets 2.5 stars and 2.2 stars, respectively) say the app is difficult to use and has limited features. Multiple users noted difficulty logging in, poor customer support and no live monitoring of their solar panels’ production, as is available elsewhere.
Are Sunrun solar panels a good deal?
Sunrun provides a lot less public information about pricing compared to Tesla, so it’s a bit harder to nail down an answer here. Given that change with location and industry experts suggest getting multiple quotes when you’re shopping for solar panels, including from non-national players, that’s probably OK. Still, we can start to get at that question without a quote in hand.
In November of 2021, Sunrun reported an installation cost of 3.93 per watt. The median cost in 2022, according to Wood Mackenzie was 2.99 per watt for an eight kilowatt system.
This is not an apples-to-apples comparison, Wyatt Semanek, a Sunrun spokesperson, said via email. Sunrun’s price per watt includes the cost of batteries with some systems, while many other available averages do not. One Tesla Powerwall can add 10,000 to the cost of a system, a significant addition. Semanek also noted that geography has a significant influence on price.
Although it’s a different beast than purchasing panels, there are a few things to know about the solar-as-service options that comprise the majority of Sunrun’s business. CNET has looked into power purchase agreements before, and Sunrun’s lease options are a different flavor within the category of third-party ownership.
According to a November 2021 Sunrun document, while about 70% of residential solar panels nationwide are customer-owned, between 80% and 90% or Sunrun’s business is solar-as-service. That means homeowners don’t own the panels, but agree to rent Sunrun-owned equipment installed on their roofs. Homeowners can get solar panels on their roof for little to no money up front and then pay a monthly fee to use them. When this fee is less than what the local utility charges for electricity, homeowners save money.
Because the cost of energy changes over time, leases include what’s known as an escalator, a year-to-year increase in the lease fee. Escalators in Sunrun leases vary from customer to customer, but a Sunrun investor presentation in May set the average escalator at 2% with a range of 0% to 2.9%. As long as your local energy price goes up by more than that each year, you’ll continue to save money.
While electricity vary by region and utility, the average American has seen go up by less than 2% per year, though recent years have seen much higher increases. Some years, utilities have requested much larger rate increases. If your lease increases by 2.9% and your utility rate only goes up by 2%, your lease could be more expensive, or at least less profitable, by the end of your 25-year term. A solar lease is usually cheaper than paying your utility for all your electricity and provides stability in a budget, Semanek said.
As always, make sure you understand the details of your agreement and how the math will work out for your specific situation, if it does at all.
Sunrun also offers the option to pay in full for a lease upfront. That financial math is harder to make work. If you can afford to pay the lease in full, it might make more sense to instead purchase a system outright and take out a small loan for anything above and beyond that.
Does Sunrun operate in my state? How do I order?
Sunrun operates in 21 states and Washington, DC and Puerto Rico.
Once you’ve confirmed Sunrun operates in your state, enter some basic information online (name, zip code, address) and wait for a call. While I didn’t go through the process of getting a quote, I did take this first step. I received a call less than two minutes after submitting my information.
Sunrun asks for a year’s worth of electricity bills to understand your needs and check your roof’s solar panel capacity using satellite images. The company sends someone out to your house to check the quality of your roof and electrical panel. Then you’ll hammer out any design details, get your questions answered and confirm the final design. The company handles permitting, and installation typically takes a day. Sunrun uses in-house installation teams and subcontractors.
Is Sunrun the best choice?
As with any major choice, it’s best to follow the expert advice to shop around. Get multiple quotes for systems and financing (if you need to finance), including quotes from local, non-national installers.
Third-party ownership generally saves you less money over the long haul than buying panels outright, which is usually the best option if you can afford the up-front cost or secure a favorable loan.
Leases can offer some savings over paying your utility and if buying solar is financially out of reach for you, a lease might be a fine option. This, again, depends on your local energy prices, the terms or the lease, including escalators and your energy usage. In this case, a lease from Sunrun might be your best choice, though you should still compare it with other lease options. Third-party ownership isn’t allowed in every state.
If you’re looking to purchase, you’ll likely get quality equipment from Sunrun. Likewise, Sunrun’s workmanship warranty matches Tesla’s at 10 years.
Sunrun’s solar offering gives you a range of options under strong warranties. It also offers choice on batteries. Like most solar providers, unfortunately, it’s hard to get an idea of costs before reaching out for a quote. This makes sense, given the variety of roofs and energy needs, but it would be nice if the industry was more transparent up front. If you enter a lease or power purchase agreement with Sunrun, you should receive quality care. Sunrun’s warranties aren’t as strong for purchases as they are for leases or power purchase agreements. If you decide to buy, you can find stronger warranties elsewhere.
It’s important to note that, while I researched this as deeply as was practical, I haven’t been through this process as a buyer and I haven’t tested Sunrun’s offerings in any empirical way. Solar services are difficult to review in the traditional sense, so be sure to get multiple estimates from different installers before you make a decision.
The 7 Best Solar Companies in Pennsylvania to Save You Money
Solar installations in Pennsylvania are becoming more popular. If you’re looking to jump on the solar system train, now is the time to start looking into the best solar companies in Pennsylvania and start saving money on your utility costs.
Let’s break down the 7 best solar companies right now in Pennsylvania to help you choose!
Sunrun is a decent-sized company that sells high-efficiency monocrystalline solar panels via popular brands such as LONGi. The company also offers two lithium-ion solar battery choices, the Tesla Powerall and LG’s Chem.
All of Sunrun’s solar panels come with a 10-year warranty. Despite being less than the 20 to 25-year industry standard, the guarantee is thorough because it covers system repairs, equipment replacement, and related labor.
Sunrun also provides a distinctive bumper-to-bumper system warranty. For ten years, there is active monitoring, free equipment replacement, and system repairs. The warranty also covers theft and damage insurance, which is rare for most companies.
Momentum Solar customers can easily customize their systems because the company offers a variety of solar panels. In addition to providing solar battery storage through a partnership with Enphase, the company also offers electric vehicle chargers, inverters, and other solar products.
Momentum installations all come with a 25-year workmanship warranty as well as a 25-year equipment warranty. These warranties provide complete coverage for both goods and labor.
Also, Momentum Solar provides a dynamic mobile app for tracking system performance. This is useful while you become used to your new system and can help with upkeep, potential repairs, and more.
Palmetto Solar sells and installs high-quality monocrystalline Q Cells solar panels and Smart home solar batteries. The company also offers a 25-year equipment and performance warranty from the manufacturer.
Customers can add the Palmetto Protect plan to their bill after their installation for a modest monthly charge. Regular maintenance, panel cleaning, pest control, and active system monitoring are all included in this plan. The plan also covers panel removal or reinstallation if you move.
Palmetto Solar is available in 24 states, including Pennsylvania. Due to their size, they can offer residential consumers solar loans, leases, and power purchase agreements.
Green Home Systems
High-efficiency solar panels from Panasonic and LONGi are available through Green Home System, a great company in Pennsylvania. They also have a special Apollo II solar roofing option. Small monocrystalline solar panels that resemble roof tiles are used in this roofing system, which hides the panels better than conventional solar systems and maintains the aesthetic value of your property.
The company offers a performance guarantee and a 25-year warranty on their products. The equipment they install is also compatible with downloaded monitoring software, despite the fact that they don’t provide their own system monitoring app.
The company offers 0 down financing for qualifying customers, which is great if you need a solar loan. However, some customers have noted that you may have to wait weeks (if not months) to get your system completely installed.
One of the best parts of Yellowlite is that they offer a physical protection warranty for up to 30 years, which is longer than most companies offer.
In addition, Yellowlite is an excellent choice because it provides a nice selection of solar equipment brands with the highest efficiency ratings. However, it’s crucial to note that their workmanship warranty is inadequate.
The company does not offer leasing options, so you’ll want to be able to pay cash or get a loan through a third party.
Paradise Energy Solutions
Paradise Energy Solutions is a small and local installer that services Pennsylvania. Unfortunately, since the company is so small, only a few cities in Pennsylvania are served by the company. But if you live where they are available, they are worth looking into.
Depending on the high-efficiency solar panels brand you choose, you’ll get up to 30 years of physical protection and a 10-year craftsmanship warranty. Keep in mind that this company does not offer leases or PPAs. So, you’ll only be able to pay in cash or get a solar loan.
Since 2014, Solar SME has installed solar panels on homes and businesses. The business installs solar batteries in Pennsylvania and six other states.
Design, permitting, installation, inspection, monitoring, and maintenance are all handled exclusively by Solar SME since the company doesn’t employ any independent contractors.
You’ll also be able to choose from a variety of solar financing plans, including leasing and a power purchase agreement (PPA). No matter what you choose, the installation comes with a 25-year warranty for equipment.
How to Save Money When Hiring a Solar Company in Pennsylvania
There are different ways to save money on your solar installation, no matter which company you choose. Here’s how.
Tax Incentives and Rebates
While the state of Pennsylvania doesn’t have many state rebates or incentives, there are still a few programs you can utilize. The best solar companies will point you in the right direction to help you take advantage of these incentives.
Another way to save money is to compare companies. We suggest getting at least three estimates from different companies. Also, be sure to research why certain companies are cheaper — as an example, would it mean a smaller system and shorter warranty?
Ask for a Discount
It never hurts to ask for a discount from the company you choose. Be sure to ask nicely, or see if there are any ways to get a discount on your system (like a referral or loan).
What to Consider Before Hiring a Company
What should you think about before hiring a company for solar installation? We recommend these questions.
Years in Service
It’s a good idea to keep in mind that the solar contractor you choose should have completed numerous installations and refined their skills. Experienced solar installers use the proper installation methods and techniques.
A professional with years of experience will also be knowledgeable about the best installation tools and equipment. We recommend a minimum of three years, but the longer the better.
Selecting the ideal solar contractor is not always simple. Examining the contractor’s credentials and qualifications is among the most crucial things to do. Requesting to see their license and credentials is a good idea. Be sure to also research your state’s licensing requirements.
Even though they are not required, certifications are a terrific way to feel secure as a consumer. The contractor needs to be certified by the Electronics Technicians Association, Roof Integrated Solar Energy, or the North America Board of Certified Energy Practitioners (NABCEP).
Contractors must have at least a year of experience installing solar panels in order to obtain these certificates. In order to keep current, they also must re-certify every three years after that.
Reputable businesses will always guarantee the quality of their job. Because of that, they should provide a warranty on the equipment they utilize as well as their workmanship. The specifics of those warranties, however, will differ from one contractor to the next.
Make sure you understand the terms of any warranties offered by the company on the equipment it will be installing and ask about them.
Trustworthy companies will have reviews and references from previous customers. Check the company’s reputation online and see what people have said about the company’s services to get an idea of quality, timeframe of installation, warranty, customer support, and workmanship.
One of the most challenging aspects of the procedure for the majority of homeowners is figuring out how to pay for their installation.
However, many businesses provide financing to spread out the expense over a number of years. This makes it easier for you to install panels and enables you to benefit from energy savings without breaking the bank. Reputable contractors will also go over existing tax breaks and incentives to further reduce the cost of your installation.
Are Solar Panels Worth it in Pennsylvania?
With everything we’ve talked about, are solar panels worth it in Pennsylvania? Because of the following incentives, we’d say yes! Here’s what you need to know.
The Federal Solar Tax Credit
You can deduct 30% of the cost of a solar system from your federal income taxes thanks to the Clean Energy Credit. Systems installed between 2022 and 2032 are eligible for the 30% Clean Energy Credit. The credit expires in 2035.
To claim the Clean Energy Credit, you’ll need to fill out form 5695 (PDF) and send it to the IRS. When you file your federal tax return for the year after your paperwork has been approved, you will be given a credit for your solar savings.
Once you have your solar system, you can sell extra solar generation to your utility company. In Pennsylvania, utilities are prohibited from charging net-metered consumers any costs that they wouldn’t charge a non-net-metered client and are required to offer net metering at non-discriminatory prices.
Solar Alternative Energy Credits
In the state of Pennsylvania, solar owners can receive one solar alternative energy credit (SAEC) for every megawatt-hour of power their system produces. Keep in mind that SAEC values change every day as a result of supply and demand, but you can use yours for three consecutive years.
Solar energy can save you money and eventually pay for itself, even though the initial cost is an investment. But where utility costs are high, like in the state of Pennsylvania, we’d say solar is worth the cost. And if you’re still looking for some of the best solar companies in Pennsylvania, you can look more into those we’ve listed!
The 7 Best Solar Companies in Pennsylvania to Save You Money FAQs (Frequently Asked Questions)
How much does a solar system cost in PA?
On average, a solar system in Pennsylvania will cost around 20,000. Of course, it will depend on your home, personal needs, and the incentives you qualify for.
Does PA have a solar tax credit?
No, the state does not have a solar tax credit at this time.
Can you sell electricity back to the grid in Pennsylvania?
Yes, you can, using the state’s net metering rule.
About the Author
Kim Studdard is a freelance writer from the South and transplanted in the Midwest. Her portfolio includes articles involving personal finance, dog treats and pet care, and technology, including the articles on History-Computer. When she’s not writing, you’ll find her spending time with her family and pets, reading, and completing her yearly bucket list.
What Homeowners Should Know About Solar Panel Cleaning
The appearance of any unknown substance on your solar panels can be a cause for concern. One of our customers recently contacted us about a dusting of white powder they saw on their panels. Our examination revealed that the culprit was pollen that had accumulated on the solar panels, so there was no reason to panic, as the panels were still producing energy, they just needed a good cleaning.
We suggested that they could start by spraying the pollen off using a water hose to clean the panels. Then we recommended that they sign up for a thorough panel cleaning service at least once per year. It would prevent build-up in the future and ensure maximum efficiency and savings from their solar power system.
This homeowner’s concerns got us thinking about the sort of solar panel cleaning questions that most homeowners have:
- Do solar panels need cleaning?
- What solar power cleaning tasks can you do on your own?
- When should you hire a professional cleaning company to clean your solar panels?
- Will cleaning your solar panels improve their performance?
This article will answer all your concerns regarding these and other questions.
What are the Causes of Dirty Solar Panels?
You need to oil, maintain, and clean your car so it runs more efficiently. Others want their house Windows to be crystal-clear and grime-free so they can enjoy the view of their property. For many of the same reasons, your solar panels also need cleaning. Accumulated leaves, bird droppings, and other debris can block a significant amount of the sun’s rays, reducing your system’s efficiency.
We all love trees, as they beautify and freshen up our property. But birds also love them for nesting or chilling spots. If branches hang over your solar panel array, you should be prepared to do some extra cleaning.
Bird droppings tend to be more notorious than dust, leaves, and pollen, especially if they harden and stick on the panels. The accumulated debris from birds can block significant light from the sun, and it’s more difficult to remove just by spraying your panels with water.
Thankfully, products and services exist that can indicate if bird droppings affect the current flow in your solar energy system. Microinverters help with this, as the technology allows you to see when a single panel is generating less electricity because of blockage or debris.
Pollen and Leaves
Pollen has evolved into a sticky material that doesn’t dissolve in water. As a result, it can be harder to clean since it doesn’t just blow away in the wind. If you live near farmlands or areas with a lot of vegitation, expect pollination agents like wind, insects, and birds carrying pollen to pass over your panels and drop some of it on them. In fact, windy weather is more likely to blow pollen onto your panels in the first place instead of blowing it away.
You may also need to deal with leaves falling on your panels, especially if your trees are deciduous, meaning they lose their leaves each year in the fall. While dry leaves just blow away in the wind, wet leaves typically stick to panels as heavy rain can act like glue.
Dust and Dirt
Dust and dirt is a common enemy of solar power systems, and its effects go beyond the accumulation of grime. It’s true that sun rays may still pass through a thin layer of dust, and wind or rainwater can quickly sweep most of it off. But if your PV array is located near dustier areas such as farmlands, main roads, cement factories, and quarries, the story changes. Your solar panels will need special attention and frequent cleaning as they have to contend with far more dust and dirt.
Now, you may be thinking, “Wait. You told that customer to use water to clean their panels. Why is it on the list?”
Fair question! The issue has to do with the pooling of cleaning or rainwater on horizontal solar arrays. Apart from simply reducing your solar energy generation, the water layer can leave a muddy residue after evaporation, necessitating more frequent cleaning.
Do Solar Panels Need Cleaning?
Like anything that stays outside every day and night, solar panels will eventually accumulate dirt. But how frequently you may have to wash your panels depends on several factors, including:
- System design
- Installation angle(s)
- Size/number of panels
- Types of dirt
- Duration between thorough cleanings
So, do solar panels need cleaning? Our definitive answer comes in three parts:
Answer #1: Yes, and You Can Do It Yourself
Bird droppings and other dirt agents can affect your solar panel’s performance, especially if your panels lie truly horizontal on the roof. That’s where washing the panels becomes important, though it doesn’t have to be a thorough or routine cleaning in many cases.
As we suggested to the customer with the white powder on their panels, cleaning your solar panels is usually a relatively easy task. All you need to do is to spray the panels with average-pressure water from a well-angled garden hose while standing on the ground.
If you want extra cleaning power, a long-handled squeegee or soft brush plus a medium-pressure hose nozzle can work wonders. With the nozzle, directing the spray will become easier. You’ll then wipe off the water using the squeegee for maximum electricity production. This approach provides even more cleaning power, but it does depend on the angle of your roof, roof height, and panel placement, because not everyone will be able to reach their roof, even with a long handle.
Answer #2: Yes, but You Don’t Need to Do Anything
Maintaining your panels is essential, but you don’t need to clean them as often as most people think. You may need to remove the occasional buildup of leaves, bird droppings, and other debris to maximize the amount of sunlight exposure your panels receive. Any regular wind and rain will typically sweep off most of the dirt, so it’s better to let nature take its course and only do one thorough cleaning every year to maximize energy production.
When it comes to doing any thorough cleaning and maintenance, it’s best to hire a professional with the knowledge and tools to get the job done safely and correctly the first time.
Answer #3: No, Unless Something Really Bad Happens
Researchers at the University of California left solar panels on a roof for 145 days without cleaning. Their findings? The panels’ energy generation efficiency dropped by 7.4%.
It may surprise you that the efficiency of your solar panels can remain intact over a long period, considering all that exposure to debris, dust, heat, and rainwater. But you can trust your panels to withstand the regular wear and tear of the elements.
Solar companies employ only the leading technologies and engineering skills when manufacturing their products. Their design processes usually account for the effects of dirt, water, and pollen from everyday use.
You still need to be on the lookout for any obvious structural issues with the panels, supports, and roofing.
Can Cleaning Solar Panels Improve the Performance of PV Systems?
As we’ve seen so far, the short answer is, The impact of dirty solar panels on solar power production depends on various factors. But we’re interested in the long answer, right? Let’s dig into the science and math a bit:
An experiment involving solar panels on a low-slope roof sought out the difference in energy output before and after a thorough cleaning.
The researchers found an average 3.5% boost in energy production (the amount of power produced over time) after cleaning the panels using a soft rag and water. The implication here is that the energy yield increase was low, despite the high amount of dirt accumulation.
Things became interesting when heavy rain did the cleaning job. The average performance increased by only 1.9% after rainwater pounded on the dirty panels. What does that mean? A good shower from the skies can take care of some cleanup, but it’s not as effective as the proper equipment and some elbow grease.
You may want to check how much your dirty solar panels are costing you in terms of energy generation. Here’s a simple formula for determining the value of solar panel cleaning:
Yearly Energy Production (kWh) × Production Loss From Dirty Panels × Electricity Cost per kWh
For example, if your residential solar energy system can produce 10,000 kWh of electricity per year, and you assume a 5% loss of production due to panels being dirty, and you pay 20 cents per kWh for electricity from your utility, your yearly cost of electricity loss from dirty panels is as follows:
A 5% electricity production loss might not sound like a lot, but it can definitely add up, and suddenly you’re paying way more to your utility company on your electricity bill than you need to be.
The Science of Cleaning Your Solar Panels
Yes, rain helps wash solar panels and keep dirt at bay, but it comes with several downsides, which can lead to noticeable performance problems on panels set at low angles:
- Rainwater comes laden with pollen and dirt
- It can pool on the surface of your panels, especially if the glass surface sits lower than the frame
- Once the rainwater evaporates, it can leave behind a muddy residue
So, should we rule out the need for cleaning solar panels? Not yet. Researchers at Google’s solar farm have a different story.
In one set of their experiments, they studied 1.6MW of horizontal solar panels on flat carports in Mountain View, California. These panels operated untouched for 15 months.
After cleaning them, they realized that the energy production from their carport solar panels had doubled overnight! Eight months later, they cleaned those same solar panels and learned that the output had gone up by 36%.
So, what’s our conclusion? All solar panels still need frequent cleaning, especially if they’re horizontal or almost horizontal on your roof. If yours are tilted appropriately, a reasonable amount of rainfall will get them mostly clean, but a scheduled annual visit from cleaning professionals may further help your overall renewable energy output.
How Can I Clean My Solar Panels?
Cleaning your solar panels doesn’t have to be extensive or risky work. If you’ve decided to clean your panels yourself, what matters is that you follow these cleaning tips to keep both you and the solar system safe.
When in doubt, just remember that you can always call in the professionals to get the job done safely and efficiently. Because some solar installers are only focused on new installations, they don’t all offer services like solar panel cleaning. If that’s the case, rest assured that Palmetto can still provide any of your solar service and maintenance needs.
Tips for Cleaning My Solar Panels
Before setting out to clean your panels, you must keep in mind one crucial point: Avoid scratching or damaging the glass at all costs. You don’t want your energy production to plummet.
When cleaning solar panels, you will always be gentle with them by using these solar panel cleaning tips and tricks:
- Solar panel models are not all created the same. It’s prudent to check with your product’s manufacturer to see if they have specific instructions for cleaning.
- Consider using a garden hose first. But if grime and dirt have built up on your equipment, it’s time for a thorough cleaning.
- Most likely, the only equipment you need is a bucket with clean, warm water, a soft cloth, dish soap, and a soft brush or squeegee.
- Pick an evening, a morning, or a cool day to do the cleaning. You don’t want to get burned by hot panels on a sunny day. If it’s too sunny, the soapy water can evaporate before you get time to wipe it away, which can leave a smear or residue that can reduce your panels’ efficiency.
- Avoid splashing cold water on a hot glass surface. It can lead to cracks due to sudden contraction.
- Apply the warm water and dish soap on the panels’ surfaces using a soft cloth or sponge. Do NOT clean the wiring underneath.
- Use a squeegee to get rid of dirty water.
- Never step on your panels, as this can damage them and cause premature failure.
- Avoid brushes with sharp bristles that can scratch your solar glass surface.
If you live near an airport or a route frequented by trucks, expect to find a few oily stains on your panels. In this case, you can use a rag and a little isopropyl alcohol to remove them.
Pro Tip: Strong cleaning fluids should not touch your expensive investment at all. Harsh chemicals and liquids like laundry detergents, ammonia, and acids can react with or streak the glass surface, leading to damages and a loss of energy production.
How Often Should I Clean My Solar Panels?
In most cases, you only need to clean your solar panels once or twice per year. We recommend scheduling your annual cleaning routine during the spring. That avoids the heat of summer and harsh elements of winter.
However, your solar panels might need extra attention in some locations. For example, the Southwest US experiences more significant dirt accumulation because of limited rainfall. Also, panels in homes near airports, factories, freeways, and other sources of pollution will need more frequent cleaning.
Winter and autumn are other special cases. Removing heavier-than-average snowfall and leaves can boost your solar performance significantly.
Do I Clean Off Snow?
We get it. heavy snowfall days can make anyone nervous about their system not generating enough energy. However, snow on your solar power panels usually melts away quickly, thanks to the heat created by the solar panels, and their slick surface. Snow on a panel melts faster than on an empty roof due to the high difference in heat between the two surfaces.
But if the snow is taking longer to melt and your battery storage is running low, you don’t have to wait. You can brush the snow off your panels to get them back to producing power right away.
Make sure you use the right equipment to avoid damaging your investment and compromising its warranty. Thus, shovels, standard brooms, and other non-specialized tools should not come anywhere near your panels. A suitable snow roof rake created for the task will come in handy here. They typically cost around 30 to 150.
Can I Use a Pressure Washer When Cleaning My Solar Panels?
No. Not at all. High-pressure water is among the biggest enemies of your solar equipment.
First, high-speed moisture can quickly force its way through the seals around the frames and get into vulnerable technology. These water leakages can promote corrosion of the fine wires, which leads to the failure of the solar panel and its photovoltaic cells.
Also, the glass surface can break under high water pressure. We hear you asking, Why then don’t we see damage resulting from continuous rainfall pounding on the glass? That’s because panels are designed to resist hours of heavy rain falling across a wide surface area. But washing the panels with high pressure directs a focused beam of water in a highly concentrated spot, which creates an increased chance of stressed areas that can crack.
What is Localized Soiling?
Localized soiling of solar panels is when material like bird poop, leaves, and any other heavy blockages get stuck on your panels, but only cover part of the panel. Compare that to general soiling, where material like dirt and dust covers the entire panel surface.
When rain and wind fail to remove localized soiling, this sort of debris may block some parts of the equipment, leading to hot spots.
Your panel is made of several individual cells (60 in most cases). When localized soiling blocks sunlight from reaching one of the cells, its energy production drops. However, full current flowing from the adjacent cells may pass through the affected one. The result is overheating at that cell, a phenomenon that can cause damage to the panel.
Yes, modern solar panels come with multiple built-in bypass diodes to keep hot spots at bay. But those extra-dirty areas can still lead to damage over time that can increase your solar panel maintenance cost.