Tag: community-scale solar

Installing PV Wire: Direct Burial, Hangers, or Conduit?

Posted on by bop-admin

PV wire doesn’t seem like a big deal, but moving generated power from solar panels to the electrical grid would be impossible without it. 

To the untrained eye, installing thousands of feet of wire seems like a pretty straightforward process. But maximizing its performance depends on several factors, including: 

  • Environmental Conditions  
  • Cost Considerations  
  • Ease of Installation  
  • Project Size

Depending on the situation, solar EPCs have a few installation options, including direct burial, conduit, and hangers. 

Direct Burial Installation 

When solar developers directly bury PV wires, they install them in trenches underneath the panel rows. 

Direct burial wire is designed for underground installation without a conduit. To ensure the wire is up to the task, it undergoes rigorous testing to earn a specific UL mark. In this case, the mark signifies the wire can withstand abrasions, crushing, moisture, chemicals, and other hazards. 

Solar companies like direct burial wire because it’s a low-cost and easy way to install electrical wiring. Workers only need to dig a trench along the panel aisle near the racking, place the wire, and cover it back up. But as easy as it is, direct burial wire isn’t appropriate for every application. 

The Good and the Bad of Direct Burial Wire 

Soft soil compositions with relatively few rocks are the best conditions for direct burial wire. Sandy soil is also a good option because it drains quickly. Drainage is vital for underground wire installations because moisture can damage wire insulation and jacketing over time. 

Direct burial wires also run the risk of damage from environmental hazards. Sharp rocks could nick wire insulation, allowing moisture to get in. Large rocks can crush the wire and its insulation, hurting performance. Even damage caused by rodents chewing on the wire can potentially create faults. 

Damage could lead to less electricity generated and create unsafe conditions. It also costs crews time, money, and long-term production since they must visit the site, dig up damaged wires, and repair or replace them. 

Underground Conduit Installation 

Conduit installation is similar to direct burial, but instead of putting the wires in the ground, they’re fished through metal or PVC tubes. 

The tubing provides an additional layer of protection on top of the wire’s standard thick insulation and works well in rocky, moist, or corrosive environments. Typically, conduit is used when crushing, abrasion, or other threats are an issue. Beyond soil, conduit protects the wire from rodents, temperature fluctuations, and accidental damage from digging. 

Unlike direct burial situations, workers can easily replace or repair wires if something goes wrong – without digging. Crews only need to pull the wire out, replace it, and fish it through the conduit pathway. 

Like any other electrical project, local regulations may dictate conduit use. Requirements could change from one municipality to the next. The National Electrical Code (NEC) also has specific standards, so keep them in mind. 

More Protection, Higher Costs 

Encasing wires in conduit offers better protection than insulation alone, but makes solar projects more expensive. 

Not only do you have to buy enough for the entire site, you need people to install it. This means digging trenches, burying the conduit, then pulling wires through the tubing to connect everything. And as utility- or community-scale solar sites get bigger, so do the associated costs and timelines. 

Conduit is also not as flexible as direct burial wire, making it harder to use on slopes and curves. Shovels or excavators could also accidentally puncture metal or PVC conduit, damaging the contained wire. 

Cable Hangers 

Hangers come in many shapes and sizes, using galvanized steel coated with thick PVC to safely hold PV wires in place from the solar panel to the combiner box. 

Unlike conduit, workers can easily bend hangers to fit whatever shape they need. And unlike direct burial and conduit solutions, hangers don’t require any digging. They connect directly to the racking underneath the solar panels and provide a cost-effective way to string PV wire quickly across difficult terrain. This makes them useful in areas where the ground isn’t suitable for digging, like brownfields. 

Depending on the number of wires carried along the pathway, messenger wires might be necessary. Unlike PV wire, messenger wires don’t carry any current – they provide strength and support to keep wires in position. 

Maintenance and repair work is also easier for operators because the wires live in the open air. Workers can find damaged wires, remove them from the hanger system, and replace them without additional equipment. 

PV Wire Hanger Considerations 

As with any electrical job, PV wire hangers fall under NEC guidelines. 

According to NEC Article 690.31 (C) (1) (b), “Exposed cables sized 8 AWG or smaller shall be supported and secured at intervals not to exceed 600 mm (24 inches) by cable ties, straps, hangers or similar fittings.” 

The rules are slightly different for wires bigger than 8 AWG, allowing hangers up to every 54 inches. For added support, messenger wires can help carry some of the weight. 

Depending on the location of the solar array, code enforcement could apply other rules. Contact your local codes department to avoid any potential issues. 

Above-ground wires also face several potential issues, including contact with people and vehicles and severe weather. Buried wires are typically hidden, but hanging wires don’t have the same type of protection. This leaves them open to damage from sun, wind, rain, snow, vandalism, and accidental contact. 

What Impacts Solar Wire Installation? 

No two installations are alike, but knowing what you’re getting into before putting shovels in the ground can make mistakes avoidable. 

Environment 

Soft soil without much moisture is well-suited for direct burial projects. If the soil is rocky, struggles with drainage, or risks contact with chemicals, conduit makes sense. If the land is rocky, too wet, or at a brownfield site, hangers are a safe, cost-effective choice. 

Cost 

Direct burial is a low-cost option but requires laborers to dig trenches. Hangers are also cost-effective but leave wire out in the elements and exposed to other dangers. 

Conduit is pricier and requires labor, time, and equipment. However, it offers solar systems the best protection from damage and exposure. 

Project Size 

Bigger sites mean more work and longer timelines. Worse yet, delays can occur if crews run into unexpected issues. 

Smaller community-scale solar energy projects take less time to wire compared to utility-scale solar projects. However, smaller sites may benefit from the added protection conduit offers without a massive hit to the bottom line. As sites become larger, costs increase dramatically, forcing project developers to limit expenses. 

Code Regulations 

Although the NEC is an excellent guidebook, follow local and state codes to avoid mistakes. 

Failing to do so could result in violations, leading to work delays, fines, or other problems. 

Know Your Surroundings 

As solar sites spring up across the United States in brownfields, farmland, and even on water, teams should carefully determine how to set up their arrays.

Whether it’s a utility company with a small solar farm in the rolling hills or a large-scale developer repurposing brownfields, having the right manufacturing partner makes a huge difference. 

Good partners understand community, industrial, and utility-scale installations and act as a guide. They can also field questions and offer insight throughout the blueprinting, development, and troubleshooting processes. 

Most importantly, companies can keep every solar job on time and within budget.

What Is Fixed Tilt, Single, or Double Axis Racking?

Posted on by bop-admin

Solar panel racking is a mundane yet vital part of any utility-scale solar installation. 

Harnessing solar energy is more than simply pointing panels at the sun. Despite looking like simple infrastructure, ground-mounted racking can vastly improve a solar operation’s overall performance. 

Racking systems allow operators to precisely angle panels to optimize generation and maximize results over the system’s lifespan. Luckily, solar EPCs have access to several types of racking systems to fit any budget, environment, or climate. 

Fixed Tilt Solar Racking 

True to its name, fixed tilt solar racking holds the solar panel at one tilt angle. 

Since the panels do not track the sun’s movement, installers must find the angle that maximizes sunlight absorption. This angle, called the azimuth, helps the panel collect as much sun as possible during peak hours. 

Azimuth angles use true north and the sun’s position to find the perfect direction to face the sun. To calculate the azimuth, developers can use the National Renewable Energy Laboratory’s Solar Position Algorithm to get results within 0.0003 degrees. 

Pros of Fixed Tilt Racking 

So, why do solar EPCs like using fixed-tilt systems for certain projects? It comes down to ease of installation and upkeep, durability, and application. 

Fixed tilt systems don’t have complex tracking systems, making them easy to install almost anywhere, ultimately saving time and labor costs. The system’s straightforward design also makes it useful across residential, community, and utility-scale projects. 

Fixed-tilt systems are more durable than other options. They need little maintenance over their usable lifespan and have a low risk of losing the sun’s position. The racking systems also do well in poor weather conditions, including where snow could be an issue. 

Finally, installers prefer fixed tilt systems when working with brownfields and other challenging landscapes. Brownfields are former industrial or commercial sites that may have environmental contaminants, making them unattractive for regular development. In cases like this, solar panel systems stationed in poured concrete hold up the panels without disturbing the ground too much. 

Concrete pads or blocks work in other challenging locations, too. Rolling hills make it hard for some tracking systems to work, but fixed-tilt systems don’t have similar problems. 

Cons of Fixed Tilt Racking 

Despite being cost-effective, durable, and easy to install, fixed tilt racking falls short in other ways. 

Because the racking system doesn’t move, solar panels don’t follow the sun through the sky. This limits the amount of sunlight the panels absorb, making them less efficient. 

Less efficiency also leads to another problem – less production. To offset the lack of production, developers may need to install more panels to achieve better results. The additional panels require space, leading to higher land costs and expenses. 

Shading can also cause issues for solar panels attached to fixed tilt racking because of their lack of movement. If a tree casts shade on a section of solar panels, their production plummets without a way to change direction. 

Single Axis Systems 

Unlike fixed-tilt mounting systems, single-axis ones follow the sun using tracking components. 

Because the system tracks the sun, panels collect more sunlight, leading to better solar power generation. Though they cost more than fixed-tilt options, their increased output means sites need fewer panels to produce the same power. 

To save money, developers can also install panels in long rows, using one drive system to control all the trackers at once. The cost is a little more burdensome in tight areas with shorter aisles because the installation requires more drives. 

Pros of Single-Axis Racking 

Single axis tracking setups are more expensive but prove their value by increasing long-term electricity generation. 

Moving, even in one lateral direction, makes a dramatic difference for most systems, including those in small spaces. Experts suggest single-axis setups are somewhere between 15-30% more efficient than fixed-tilt ones. This is because panels can keep pace with the sun all day. 

Furthermore, single-axis racking reduces impacts caused by shade. As the sun moves, the panels follow, as opposed to becoming trapped at a bad angle for hours on end. 

Cons of Single-Axis Racking 

When you introduce more complexity to a system, you increase the risk of something going wrong. 

While fixed tilt systems offer an easy-to-maintain, no-frills experience, single-axis systems need more maintenance. They also require space to allow the panels to safely move along their axis. When space is an issue, there may be less room for panels. 

Increasingly complex systems also come with higher price tags, as developers can expect to pay more for a single-axis system, compared to a fixed tilt one. Though the price may cause some cost-conscious developers to shy away, the added generating power helps soften the blow. 

Finally, it’s worth noting that single axis tracking systems don’t always perform well on difficult terrain. Whether it’s hilly areas, brownfields, or other tough conditions, setting up panels in one row is hard. As a result, solar EPCs must find creative ways to safely run these systems. 

Double (Dual) Axis Systems 

What’s better than a solar panel that follows the sun across the sky? How about a solar panel that tracks the sun’s elevation at the same time? 

Not only do double-axis trackers follow the sun east to west, but they can also move north to south, tracking elevation too. PV systems outfitted with dual-axis solar racking systems are up to 40% more efficient than standard fixed tilts. The result is a system capable of generating maximum electricity every day of the year. 

Pros of Double-Axis Racking 

One benefit of being incredibly efficient is that installations can often do more with less. 

When panels follow the sun better, farms need less space and fewer panels to achieve similar results. For developers, it means getting more power out of the same plot of land, reducing project costs. 

More importantly, double-axis tracker systems can negate issues caused by shade or clouds. When shade covers the panels, they can be repositioned, optimizing the situation and generating clean power. 

Cons of Double-Axis Racking 

Better technology often means higher costs. 

For some solar developers, the high upfront cost to install double-axis racking can be a tough pill to swallow. Unlike fixed-tilt trackers, these complex systems often require skilled workers to install, calibrate, and maintain them. 

Maintenance is critical to keeping a double-axis system running smoothly. If the trackers don’t work, they can’t follow the sun, hurting overall production and return on investment. However, with proper maintenance and care, the farm can “pay” developers back over time. 

Finally, it’s possible that even with proper maintenance, tracker components may wear out before the panels. Panels can go decades with only routine maintenance and cleaning, but moving parts tend to show wear and tear much sooner. 

Options for Every Installation 

Every installation is different, so developers and their teams should decide what racking is best for their situation. 

Budget-friendly options are easy to install and perform well across a variety of landscapes but are less efficient. Tracking systems dramatically increase energy generation but are more expensive and need more maintenance. 

No matter what, work alongside qualified companies and partners who understand your project’s needs and goals. Their experience and expertise can help you avoid pitfalls and navigate unexpected problems, making installations smoother and more productive.

What is Community-Scale Solar?

Posted on by Mike Zimm

When most people think about solar installations, two types generally come to mind: rooftop and utility-scale. 

Rooftop or backyard residential PV solar panels provide enough electricity to power a home or small business. Meanwhile, utility-scale operations are designed to power towns, cities, and even regions. 

But there’s a third option emerging in the U.S.: community-scale solar. Larger than residential but smaller than utility-scale, community-scale installations range from a few megawatts to tens and power communities. 

Small Footprint, Large Impact 

True to its name, community solar projects are small, usually less than 5MW, but can generate enough electricity to power thousands of homes. 

Unlike utility-scale solar locations, which utilities develop on owned land, community solar farms live on leased land and get installed by EPC (Engineering, Procurement, and Construction) solar companies like Schuler-Haas, Nexamp, and TerraForm. Once complete, residents and businesses can subscribe to the site and receive credits. 

Smaller solar arrays are picking up steam in several states, including New York, California, Minnesota, and Massachusetts, but can be found in more than 40 states, Washington D.C., and Puerto Rico. Although solar installations were down 16% in Q2 2023 compared to 2022, about 226 MWdc of solar was added to the grid.  

The good news is the Solar Energy Industries Association (SEIA) expects growth from 2024 through 2028, thanks to better policies and more interest. 

How Does Community Solar Work? 

Community-scale solar is unique in size and operation, making it viable for people who can’t fully invest in solar but want to participate. 

Unlike installations owned by a single person, business, or utility company, community solar projects benefit groups of businesses and individuals throughout the service area. They can either pay to own a portion or subscribe to a community solar installation, allowing them to collect solar credits on their electricity bills. 

But what are solar credits, and how do they work? As the solar array generates electrical power, subscribers and owners collect credits based on the electricity produced. Those credits are then applied to their utility bills. 

According to the NREL, about 49% of households and businesses can’t have rooftop solar. For those who can’t afford a residential PV system or don’t have the right conditions to support one, community solar is an option. 

Even better, the energy produced by community solar goes straight from the array to the grid and is delivered directly to those living nearby. 

Is Community Solar Worth It? 

With all the talk of subscriptions and credits, community solar sounds complicated, but it’s a popular choice for consumers and builders for several reasons. 

  • Accessibility: Community solar allows people to invest and benefit from solar installations with a low-risk investment. They still reap the rewards of solar power without the massive upfront purchase to install panels. 
  • Cost savings: Community solar is a low-cost electricity producer compared to traditional fossil fuels. 
  • Supports the local community: Solar installations create jobs and can support sustained regional economic growth. 
  • Varies energy sources: Renewables can support traditional fossil fuels during periods of high demand. They can also help supply power in the case of an emergency when fossil fuel sources are offline. Solar arrays also help develop microgrids, which limit the spread of blackouts if a problem arises. 
  • Cleaner energy: Solar panels produce no by-products, and the sun is an infinite fuel source. Energy storage and consistent production are still troublesome, but the technology needed to address and mitigate those problems is quickly evolving. 

Of course, not everything is perfect. Every investment, including community solar, has inherent risks. 

Drawbacks and Concerns 

Despite renewable energy projects earning the praise of agencies, organizations, and the public, every emerging technology has its fair share of challenges. It’s especially true when attempting to integrate them into older installations. 

  • Interconnection Issues: According to a 2022 White House statement, about 70% of U.S. transmission lines are 25 years old or older, with many pieces coming online in the 1960s and 1970s. Unfortunately, that makes it harder for solar installations to integrate. In those situations, the difficulty of integrating leads to expensive delays, long waiting lists, and high connection fees to cover costs. 
  • Overpowering the system: Substations are designed to handle occasional overcharges or power surges, but not constantly. When a massive influx of electricity is added to the grid too quickly, it can lead to outages and damage. 
  • Location issues: In rural communities, solar installations may be miles from load centers. Getting power to the load center for distribution means more money, time, and labor is needed. These costs ultimately lead to a higher project cost and delayed ROI. 
  • Storage Issues: Solar energy is infinitely renewable but hard to store. Effective battery solutions are available but are expensive, and the technology hasn’t reached its full potential yet. Storage also becomes an issue in places where the sun isn’t shining every day and locations where snow is an issue. 

As technology improves and more utilities invest in renewable technology, it will become easier to interconnect with the larger grid. In the meantime, smaller installations can create microgrids that connect to the larger grid but reduce the effects of an outage in their communities. 

What is the Growth Potential? 

Thanks to several pieces of federal legislation, solar and other renewable energy sources are having a coming out party. 

Solar has accounted for about 45% of all new electricity-generating capacity added to the electrical grid this year, including 226 MWdc of community solar in Q2 2023. The good news doesn’t end there, as experts claim more advancements are coming. 

Global research organization Wood Mackenzie recently touted the strength of community solar, suggesting the industry could grow nearly 120% through 2027. The report also notes that the country could add another 6 GW of electricity to the grid by then. Currently, about 5.27 GW has been installed. 

Several states are leading community solar solutions, including New York, which hosts about half of the U.S.’s installed total. However, new laws, including the Inflation Reduction Act (IRA), have put solar in a much stronger position in the coming years. 

The IRA coincides with a 24-month moratorium issued by the White House on solar panels from four Asian countries: Thailand, Vietnam, Malaysia, and Cambodia. The moratorium expires in June 2024 and is designed to help get domestic solar production off the ground while giving companies and utilities access to lower-cost solar panels to complete ongoing projects. 

Domestic production is expected to improve for balance of system products like PV wire, panels, and racking materials, and organizations like Wood Mackenzie and the SEIA are confident the industry will flourish. 

High Potential, Low Cost of Entry

There are plenty of tax credits and incentives to get people involved with residential solar, but barriers to entry are still high. Options like community solar reduce investment costs while helping people do something good for the community, the environment, and their wallets. 

It also comes in handy for people living in low-income and rural areas, where credits can impact how much they pay for the electricity they consume. Rural locations also tend to have more space for solar installations, shortening the distance from the array to a load center. 

The benefits of community solar are undeniable, but there are still hurdles. Our electrical grid is rapidly aging, making it difficult to efficiently interconnect with existing substations and other infrastructure. If the substations and grid technology are too old, it will be harder to integrate efficiently. 

We’re getting closer to a world run by renewables. More advancements mean more opportunities for good-paying jobs, low-cost electricity, and better resilience in the face of storms and other emergencies. It will take time, but a renewable-powered future is possible.