Quality O&M Services Maximize Commercial Solar ROI

The prodigious growth of solar power in the United States has turned what was once a boutique industry into a multibillion-dollar asset class. Cumulative installed solar photovoltaic (PV) capacity in the US has exceeded 20 gigawatts, with thousands of projects scattered across the country.

The prodigious growth of solar power in the United States has turned what was once a boutique industry into a multibillion-dollar asset class. Cumulative installed solar photovoltaic (PV) capacity in the US has exceeded 20 gigawatts, with thousands of projects scattered across the country.

With gigawatts now in play, this burgeoning stable of solar asset investments needs to be properly operated, maintained and managed. Commercial solar system owners, building hosts and other stakeholders require professional operations and maintenance (O&M) services for each solar project to realize its full value potential. PV systems that do not have scheduled maintenance programs to support the product and power production do not typically provide the best ROI for the customer.

From a Cost-Center to Value-Add

Until recently, the prevailing view of commercial solar O&M focused mostly on the more janitorial and repair sides of the service: keeping the vegetation trimmed, cleaning modules, replacing faulty inverters, and monitoring the performance of the PV array. O&M has been seen by some developers and EPC firms as an annoying cost center or “necessary evil,” one that could be downplayed (and under-budgeted) to make a project pencil out in the face of constant downward cost pressures. This compunction to cut construction—and services—costs to enhance short-term profits can have a negative impact on the longer-term operational health of the system.

The largest hidden cost to under-appreciating O&M is failed power production expectations. Customers plan, forecast and budget based on the expected power that is estimated during design and construction. A PV developer’s future financing can be seriously affected by an underperforming project. Expensive material repair costs and additional resources to manage and repair the asset can add up quickly. Damage to the builder’s and the solar industry’s reputation to provide a cost-efficient energy alternative is also very costly.

A growing number of investors, EPCs and asset owners now realize that O&M and related services require a more holistic, value-oriented approach, one that is baked into the system design and procurement stages and continues forward all the way through the life of the project. To get the maximum return on investment, the combination of a well-designed, well-built system and a prudent O&M plan offer the best chance for success.

The operational success of a commercial solar power plant requires that all of the parties involved—system owner, building host, O&M team and monitoring firm—agree to clearly defined roles. There are many reasonable ways to slice responsibilities, and that’s why all parties need to know their roles and expectations within the larger project maintenance strategy.

From Reactive to Proactive

Developing a proactive, site-specific O&M schedule is the first step to maximizing the long-term value of a new solar project. An ounce of prevention can save you a pound of maintenance costs. The key to doing this effectively is to determine exactly how much preventative service should be done to maximize long-term system value.

For example, one of the most important – and commonly missed – preventative maintenance services is inverter filter cleaning.  Manufacturers typically require an annual preventative cleaning of filters to maintain warranty status. Just as dirty panels produce significantly less than clean panels, dirty inverter filters reduce the inverter’s efficiency, and can ultimately suffocate the inverter. Failure to schedule regular inverter maintenance could lead to project downtime and significant rework expenses.

Half the battle is knowing what potential issues to look for and expect. Not every solar power system has been created equally, and over the years we have seen some patterns emerge in the types of issues that impact system performance, especially among arrays built in the earlier part of the solar boom. An asset owner’s approach to these issues will help determine the long-term profitability of the investment.

One of the more common issues we have seen emerge is ground faults: poor wire management often results in the inverter receiving a ground fault that shuts it down. In order to fix the problem, we send an electrician out to the site to find the ground fault and then replace the fuse on the inverter to get the system back online.

In some situations, bad wire management can lead to ground fault after ground fault, running up long-term bills and reducing the project’s profitability. This is true for many other O&M issues, as well: if a project was not designed and built properly, the asset owners could spend years battling recurring O&M problems. Ultimately, the best way to avoid unnecessary O&M work is to ensure that the system is built right the first time.

The Value of Documentation

Reputable service providers will always provide reports upon completion of any maintenance service. This documentation is vital to the effective maintenance of the system. It details the scope, schedule and service history that is unique to the system. It can and will save the manager or owner time and money in the short and long run of the power systems service life.

Maintenance documentation can be an essential requirement when addressing warranty coverage and many warranty holders will not provide service without it. Though documentation may require more involvement on the owner or manager’s side, it reduces risk and allows greater scrutiny and protection of your investment.

REC Solar provides turnkey O&M services for projects in a variety of stages – starting from the initial build and carrying through to end-of-life. We’ve performed corrective action for a variety of solar projects with a variety of compositions. To learn more about our O&M capabilities or to request a consultation, please send us a note!

Winter is Coming: Operating and Maintaining Commercial Solar PV Systems in Snowy Conditions

The operations and maintenance of commercial solar photovoltaic systems requires a year-round effort, but performing the necessary O&M tasks on installations located in geographies prone to harsh wintertime conditions presents unique challenges.

The operations and maintenance of commercial solar photovoltaic systems requires a year-round effort, but performing the necessary O&M tasks on installations located in geographies prone to harsh wintertime conditions presents unique challenges.

A well-constructed commercial solar system is highly resilient to extreme weather conditions; however, heavy snow combined with high winds could dampen the energy production of a PV array and possibly damage a system’s structure and components. A well-organized commercial solar O&M program can help avoid or rectify issues caused by the hands of Mother Nature.

As winter approaches, it’s important to make sure that all the scheduled maintenance on the system, preventive and corrective, is completed to proper specifications. Landscaping under an array should be done to remove any obstacles that would impede the free flow of snow or wind. The wire management, fasteners and torquing all need to be buttoned up, and the system must be configured to prepare for winter. For example, if the system is ground mounted with trackers, it’s necessary to adjust the trackers to the proper configuration for winter and snow conditions. Overall, the system must be in good operational condition before the start of inclement weather.

Weather forecasting and monitoring are also critical aspects of a winter O&M program. At REC Solar, we’re always monitoring the latest forecasts so that our team can prepare the system accordingly. We also check the weather conditions as they happen at the site in order to mitigate the risk of any real-time operational issues. Throughout the winter, the REC team collects detailed weather data to correlate performance with those days or weeks when large amounts of snow fell.

The placement of still and video cameras provides a real-time window into on-the-ground (or roof) conditions. There is nothing like a live visual on the system to see whether rolling a team to the installation is necessary to deal with a frozen, heavy load of snow atop the array or if the results of yesterday’s blizzard will soon melt and slide off the panels.

It’s also important to have qualified service resources, in some cases subcontractors, available in the affected regions. Keep in mind that when a big storm rolls through, the ability to react will be impacted by a number of factors, particularly road and infrastructure conditions.

Solar PV systems located in remote or rural areas can be particularly difficult to access if snow has blocked the roads or left a thick frozen layer around and on top of the arrays. Supply chains will be taxed by the intemperate conditions, and replacement modules, combiner boxes or other parts may be delayed in arriving at the job site. This issue can be alleviated by preparing in advance and holding an appropriate quantity of working inventory before the storms hit.

As with O&M challenges in general, a well-designed, well-constructed, properly load-rated PV system won’t be subject to the kind of wintertime performance and operational issues as one built with less attention to quality. For example, on a ground-mount array, the lower leading edge must have sufficient ground clearance, so that when there are high snow or wind conditions, the snow can pass smoothly underneath the array.

Flush-mount and other rooftop arrays can be challenging to maintain in wintry conditions. A large amount of snow can accumulate because the panels are installed with little or no tilt, and there’s nowhere for the snow to slide off. In this case, access to the conductors underneath the modules on a snow-covered system becomes difficult. Vigilant monitoring and tactical maintenance efforts such as snow removal are required to stay abreast of any load-related or performance issues, to lessen the risk of damage to the structure or the PV array.

When spring arrives, a winter production analysis should be performed on any alarms and alerts that have been logged. Thermal expansion and contraction caused by extreme weather can bring about racking and mounting structural issues. The array should be inspected for corrosion as well as for damage from high winds or snow load. It’s also important to scrutinize the ground for settling and possible erosion that could reveal issues with underground conductors and connections. Once the inspections and necessary remediation efforts are complete, it’s time to schedule regular springtime maintenance activities and get the system ready for the sunny, high-performance months ahead.

The seasoned REC Solar team has experience with all kinds of PV systems and weather conditions and provides a comprehensive, end-to-end service whether the summer sun is shining or the frosty days of winter are coming. We provide our customers with long-term O&M contract options, so you can rest easy by the fire knowing that your commercial solar system is in good hands.

If you have more winter, spring, summer or fall solar O&M questions for your facility, or want a free solar evaluation for your business, please contact us today!

 

‘Tis the Season for Snow and Solar Panels. What To Do?

One of the myths of solar is that it doesn’t work in cold climates. In fact, solar panels are moreefficient — produce more energy with the same amount of sunlight — in colder climates, such as Colorado and New Jersey, two leading states for solar installations. The downside of winter is that there are fewer hours of daylight, so there are fewer hours of solar production. And then there’s the occasional snowstorm….

One of the myths of solar is that it doesn’t work in cold climates. In fact, solar panels are moreefficient — produce more energy with the same amount of sunlight — in colder climates, such as Colorado and New Jersey, two leading states for solar installations. The downside of winter is that there are fewer hours of daylight, so there are fewer hours of solar production. And then there’s the occasional snowstorm….

How do you clean off snow from rooftop solar panels?

Believe it or not, the best and easiest way to get snow off a rooftop solar array is to do nothing. Zip. Zero. In the words of Tony Soprano: “Forget about it.”

There are several reasons for this method. First, it works! The winter sun does a great job of melting the snow off of the solar panels. It may take a day or two after the storm, but solar panels are typically installed with enough of a slope to let the warm sun and gravity do the trick.

Second, and perhaps more importantly, you could be risking your life or cause yourself serious injury if you try to brush the snow off yourself. Even without snow, rooftops can be dangerous. With snow and ice, they’re even more hazardous. Having snow on your panels for a day or two will reduce your energy savings, but it’s not worth risking a hard fall for that.

“Don’t go up on a snow covered roof unless your name is Santa Claus or you have some other kind of magic. Not worth it,” says Carl Siegrist, a solar consultant and member of the North American Board of Certified Energy Practitioners (NABCEP), the leading solar installer testing and certification organization.

You might think about getting a long pole squeegee or brush and combing the snow off, but here again, it’s dangerous. You could have 100 pounds or more of hard, frozen snow fall on you, once again, risking injury.

Finally, consider that improperly cleaning off snow or ice may damage the panels. Jeff Spies, a solar roofing expert and board member of NABCEP cautions, “If you are going to remove snow, take great care to avoid scratching the modules. If there is ice buildup on the glass, do not try to remove it by scraping, as you can damage the micro-etching of the surface of many glass modules, reducing module efficiency.”

Whether in the sun, rain, or snow, Spies recommends never cleaning solar panels with harsh chemicals or abrasive materials. Even a dirty mop could scratch the solar panel’s micro-etching. If your solar panels are soiled, some water with a little bit of soap and a hose is all you need.

Removing snow from commercial solar installations.

For ground or pole mounted solar PV panels or most commercial solar applications, you’re on the ground or a flat surface, so it is safer to remove snow with a soft brush. However, the same risks apply. So, just brush off the loose snow, and once again, don’t try to scrape off any frozen snow or ice.

If you’re a commercial business and need to get those panels cleaned off right away, leave it to a professional. REC Solar and other solar companies provide solar operations and maintenance (solar O&M) services that will take care of snow and make sure your system is working optimally, no matter what the season.

If you have more questions about snow and solar for commercial applications—or any questions about solar at all, please feel free to contact an REC Solar expert.

 

On A Commercial Solar Roof, Should my Solar Arrays be Ballasted or Attached?

At first glance, using a ballasted solar racking system seems like an easy choice because there will be no roof penetrations. However, depending on the structure of your roof and other environmental factors such as wind, an attached racking system may be a better choice, and possibly less expensive.

At first glance, using a ballasted solar racking system seems like an easy choice because there will be no roof penetrations. However, depending on the structure of your roof and other environmental factors such as wind, an attached racking system may be a better choice, and possibly less expensive.

First, know that an experienced solar installer like REC Solar will have a structural engineer assess your roof for the suitability of either racking system.

  • Are your rafters strong enough to handle the extra weight of a ballasted system?
  • How old is the roof?
  • What type of roofing membrane is it, and can a racking system be attached to it instead of rafters?

Beyond that, our solar PV designers will have to consider any existing roof obstacles, such as air conditioners, vents, and satellite dishes, as these may also affect your racking choices.

With that in mind, let’s look at each type of commercial roof racking system’s advantages and disadvantages.

Ballasted Solar Racking Systems

Advantages:

  • Few to no roof penetrations. The clear primary advantage to ballasted solar racking systems is that they don’t penetrate the roof…in general. However, there are some hybrid ballast systems that will need some type of physical attachment to the roof, although there will be fewer penetrations than a fully attached racking set. In addition, if your building is in an earthquake zone, seismic codes will require some minimum attachments.
  • Faster to install. Without the extra care and logistics of roof penetration hardware, fully ballasted installations can be easier and faster to install, thus reducing labor costs.
  • Typically lower profiles. For customers that want solar panels to minimally affect the roofline’s appearance, ballasted systems can be more discreet because they’re usually installed with a lower angle, so as to minimize wind shear.

Disadvantages

  • Heavier weight on the roof. By their nature, ballasted racking systems will be heavier than attached systems. Not all roofs will be able to support the extra weight, so a structural engineer will have to perform a thorough evaluation during your site analysis.
  • Potentially more expensive. The costs for ballasted systems and components can be more than attached racking systems. However, depending on the experience of the solar installer, this extra expense may be offset by a faster installation, which will lower the labor costs.
  • Less flexible. Ballasted systems can be very kit-like, not allowing for much flexibility. That inflexibility means engineers will have to find more creative work-arounds for an odd roof shape, uneven roofs, and rooftop obstacles, such as HVAC units.
  • Roof maintenance may be more difficult. Because ballasted systems can be less flexible in their designs, they may impede access to panel cleaning and maintenance if modules are positioned too close together. If there’s more space between rows of modules, then there will be less room on the roof, and hence fewer solar panels may be installed.

Attached (Roof Penetrating) Commercial Solar Racking

Advantages

  • Lower product and component costs. While more skilled labor is needed to install a non-ballasted system, there’s typically a lower upfront cost for the racking and components.
  • More flexible. Because attached roof racking structures are less of an all-in-one solution, it can be more flexible for working around roof obstacles, such as HVAC units, vents, satellite dishes, water towers, etc.
  • Potentially more solar panels on the roof. Attached racking can be more customized, so solar engineers may be able to squeeze in more solar panels, and therefore, the customer may be able to harvest more energy.

Disadvantages

  • Roof penetrations. In order to anchor the racking system to the roof, the roof will be penetrated with multiple large screws that not only go through the roof, but may also have to be attached to internal building structures. Of course, an experienced installer like REC Solar will properly use the manufacturer’s flashing, as well as other water sealants so that no leaks trickle into the building structure.
  • Higher labor costs. Attaching the solar racking to the roof requires more skilled labor in order to prevent leaks. It will also need more scrutinized safety and quality inspections, adding to the cost.
  • More involvement with the roofing manufacturer and other roof stakeholders.Because you’ll be penetrating the roof, the roofing manufacturer and original roofer will want to be involved in order to preserve the remaining years left of the roof’s warranty. Ballasted systems will still involve these stakeholders, but to a lesser degree.
  • Higher tilt. If the building owner is looking for discretion, attached racking systems can often have a higher tilt, and therefore, a higher visibility to the street.

When considering a rooftop solar system, building owners rely on their solar installation partner to help navigate the many assessment factors to help choose the right racking system. This is why it is critical to select a trusted partner with demonstrated experience. REC Solar has over 10,000 installations and has worked with all types of commercial and industrial roofs and solar racking systems. Our experienced structural engineers and solar designers will help you choose the right system for your roof.

Contact us for more specific questions about your roof.