Tag Archives: solar trackers

Challenges for Operations and Maintenance in the PV Industry

As mentioned in an earlier post, the importance of operations and maintenance (O&M) of solar power plants is growing throughout the global market, particularly in Europe. One major reason for this growth is that operators of these systems are faced with increasing challenges and have to come up with new solutions to combat them. Creating an operations and maintenance team is one such solution.

Some of the most common challenges these teams face are sand, microclimates, and crime. While each of these factors may not affect every solar power plant, understanding what they are and their impact on productivity can help companies prevent possible problems and maintain maximum efficiency.

Blowing sand

Sand

The climate in the location of a solar plant can impact efficiency. Because trackers are often situated in desert climates, sand and dust can cover the modules. In fact, many companies are looking to implement frameless technologies in their systems, as edges often act like a sand trap and collect excessive dust. If sand is not cleared regularly, it can build up and potentially shut down operation for a period of time. Any downtime is essentially money lost for a plant, as it’s critical to collect as much solar energy as possible every day.

While some firms have hired teams to regularly vacuum the panels, many are requiring the assistance of water to rinse sand away. This poses an additional challenge, as these climates often are dry and the cost to ship water in the large amounts necessary can be extremely expensive.

Microclimates

While having solar plants in dusty climates is a challenge by itself, different microclimates within these areas can cause additional problems.

In certain regions of these dusty climates, humidity comes into play. If an area experiences low-lying humidity, either near coasts, agricultural areas or regions that see light rain, the dust can turn into mud. This is more difficult to clean and creates darker shade spots on the panels, which interferes with sun collection.

Crime

Since solar power plants are often located in isolated areas, crime can be a big challenge for tracking systems. In newer markets, theft has been a problem for many companies and plants are starting to require extra security. Some have employed guards to prevent crime, hiring locally to support the nearby neighborhoods and encourage community buy-in of the plant.

As more O&M teams are created to help minimize the impact of these challenges, intelligent strategies and integrated solutions become more critical to maximum efficiency.

Top Considerations for Optimizing O&M of Solar Power Plants

Operations and maintenance (O&M) of solar power plants are becoming increasingly important in the global photovoltaic (PV) market. While an increasing number of new builds show industry growth, optimizing operations and maintenance is a cost-effective way to improve performance for plants already in use. In fact, many solar power companies are developing more intelligent strategies and practices for O&M. This may include hiring a professional service provider in some cases.

Whether getting outside help or not, there are a couple of factors to consider when looking for ways to improve operation and maintenance of solar power plants:

  • Size
  • Location

Optimizations for either of these considerations can result in improved, more reliable performance. According to a report from PV insider, a 1 percent increase in direct sun exposure can result in $1 million extra in a year’s revenue. With those kinds of numbers, it might be a good idea to explore how to improve a plant’s function, which can be achieved through more strategic O&M.

Size

The size of a solar power plant has a great effect on O&M optimization techniques. For large, compact PV projects, having an in-house operations and maintenance team makes sense. However, if the project is smaller but more spread out, outsourcing to a contracted third-party in the specific regions of the plants may be more efficient.

Additionally, size impacts how you approach power plant operation and maintenance. If the plant is small, the entire project may be tested and adjusted once a year to maximize performance. On the other hand, a system check on a large project may take days to complete, which can result in greater downtime. For this reason, different sections can be checked at different times so improvements can gradually be made and tested against the plant’s overall performance.

Location

When a solar plant is located in a desert area, as they often are, the trackers get more sun exposure, but also have to deal with the elements. Blowing sand collects on tracking devices and can interfere with energy production. This means the sand needs to be washed away frequently, but water is not always readily available in these dry areas. Coming up with an efficient O&M process for minimizing environmental factors is critical to a project’s performance. Solutions could include anything from having a dedicated team on-site to clear sand with vacuums as it builds or using self-calibrating robots that wash away sand with minimal water waste.

Every solar power project is different and therefore will require different solutions for maximum energy collection. Even a plant perfectly designed and installed to precise specifications can be improved once up and running. An O&M strategy has become critical to the long life of a project and is a growing industry worldwide.

Solar Market Growth Research: Global Single-Axis Solar Tracker Use Is on the Rise

The solar power industry is starting to see a shift in applications across global markets. According to Information Handling Services (IHS), use of photovoltaic (PV) solar trackers is on the rise. In 2013, only about 11 percent of ground arrays utilized PV trackers, but the projections for 2015 for the use of this equipment are as high as 20 percent for the global solar market.

It’s not just projections suggesting solar market growth, but there is also data to back it up. Research from IHS found that 4 GW of tracker installations were mounted in 2014, which is more than 60 percent higher than the previous year.

Single-axis solar trackers

Part of this growth may be attributed to the increasing popularity of single-axis solar trackers. These systems rotate on an axis to follow the sun as it moves throughout the day, which results in increased energy yield. This trend is expected to continue for large-scale, ground-mounted solar plants around the world because greater energy yield results in greater return on investment. In fact, IHS predicts revenues for global single-axis tracker systems will increase 120 percent by 2019, to $2 billion.

While the global market is seeing this trend on a larger scale, in particular, research suggests single-axis systems will be the preferred technology for North America by 2019. IHS also concluded that China and India are likely to be second and third in use of single-axis trackers in the next five years, with installations amounting to about 2 GW. Presently, these two nations prefer fixed-tilt trackers, but as discussed at SNEC 2015 in Shanghai, the use of single-axis solar tracking systems is on the rise in these markets.

Whether these projections are met in the coming years is yet to be seen, but the substantial increase from 2013 to 2014 suggests sun-tracking systems are on pace to grow exponentially.

More Solar Power Plants Increasing ROI Through Single-Axis Tracking Systems

Kinematics at SNEC 2105Kinematics attended the 9th Annual International Photovoltaic Power Generation Conference and Exhibition (SNEC 2015) in Shanghai last month and impressed many customers with the solar tracker reliability that comes with the use of slewing drives. The conference also initiated conversations about the solar power industry and where it may be going in the near future.

Projections in recent years have suggested Americans will continue to increase development and efficiency of solar power systems through the use of trackers that move on an axis. By 2019, the American solar tracking market will be the biggest it has been, making up about 36 percent of the global market, because of these new, more productive innovations.

Currently, the most commonly used trackers around the world are fixed, angled systems, but several American companies, such as SunPower, First Solar, SunEdison and other engineering, procurement and construction (EPC) companies, are using single-axis, rotating solar tracking systems instead. Evidence suggests these systems that follow the sun seem to be more efficient and get greater return on investment than fixed-tilt trackers.

Kinematics discussing solar trackers with the president of Asiana at SNEC 2015

In China and India, the preferred solar power system has been fixed-angle trackers because of the vast number of steel frame suppliers and low labor cost. However, single-axis tracking systems are gaining popularity quickly and starting to take more of a share of the solar power market. In fact, existing EPC companies in these regions are expected to develop new products based on the technology used in the tracking systems designed to follow the sun.

By moving in this direction on a global scale, sun-tracking systems should have explosive growth in the coming years.

Solar trackers at SNEC 2015 in Shanghai

To reduce cost in the Asia market in the immediate future, the efforts receiving much of the focus include finding ways to lower the cost of silicon material, high-efficiency cells, modules, inverters and steel frames. As far as efficiency goes, it is also critical to explore innovative methods that improve the generating capacity of solar tracking systems through smart operation and stronger monitoring.

Mounting Made Easy: The Kinematics Spherical Adjusting Base

Slewing drives can make solar trackers more efficient and functional, but they need to be mounted appropriately for maximum, reliable use. When a slew drive isn’t mounted square and level on its base, it can add tension to the whole system. This can lead to fatigue and cause damage in a short amount of time.

Additionally, the post or pillar the slewing drive is mounted on has to also be precisely positioned for maximum performance over time. Achieving the proper alignment requires time-consuming and complex installation, which includes the machining of adjustment instruments, such as shims, washers, and ovular holes.

To avoid these issues, Kinematics has designed and created a new spherical adjusting mount for slewing drives attached to solar trackers. This mount is easily installed on an I-beam, column, or tubular post in the field and adjusts simultaneously in three directions of orientation. It allows operators to easily align a mounted slewing drive to make sure it is square and level, even if the post isn’t perfectly positioned.

Kinematics Spherical Adjusting Base

Without having to worry too much about the post and whether it’s perpendicular to the ground, installation can be quicker, which can save time and money. The quick aligning and mounting features also ensure there are no residual stresses in the system, preventing elements along the line from breaking down prematurely.

The spherical adjusting mount is attached to a slewing drive containing a housing with a bottom side. This mounting structure is made up of a plate assembly, concave base plate, post coupling, clamp ring, and fasteners that couple the plate assembly and clamp ring together. The fasteners can be bolts, screws, or clips, or the post coupling can be secured in position by welding or gluing the pieces together.

Because the fasteners can easily move between the clamped and unclamped positions, they can prevent or allow relative movement between the plate assembly, clamp ring, and base plate. When the slewing drive needs adjustments, the mounting structure can be loosened to the unclamped position to allow for accurate positioning. The spherical surfaces of the plates form a socket that makes realignment a simple task. Once the slew drive is in place on the post, the fasteners can be tightened back to the clamped position and will stay secure until unclamped again.

The spherical adjusting mount is available on all Kinematics VE slew drives, which are most frequently used in single-axis solar trackers to maintain stability and precision placement. These fully-enclosed, vertical drives require no extra components to mount, and with the new spherical adjusting base, require minimal time and effort to align trackers appropriately for direct solar energy consumption.