Solar Lights for Public Art Installations

Installations of public art have the ability to inspire communities, change environments, and tell tales. It can be difficult to make sure these works remain noticeable and have an impact after nightfall, though. This is where solar lights come in, providing an effective and environmentally friendly way to light up public art while also boosting its aesthetic appeal and usability.

 

Because they are easy to install and environmentally sustainable, solar lights are a great option for public art installations. Solar lights don’t need complicated wiring or access to electricity networks like conventional lighting systems do. They are an affordable and low-maintenance choice because they use solar energy during the day and turn on automatically at night. This is particularly beneficial for outdoor art projects in parks, plazas, or remote locations where electrical infrastructure may be limited.

 

Solar lights come in a variety of designs, from sleek, modern fixtures like the solar eagle eye wall lamp to more decorative options such as the solar hexagonal pavilion lights, allowing artists and designers to seamlessly integrate them into their installations. Whether it’s highlighting a sculpture, accentuating a mural, or creating a pathway around an art piece, solar lights can be strategically placed to enhance the visual impact of the artwork. For instance, the solar color changing landscape lamp offers adjustable brightness and a spectrum of colors, providing endless creative possibilities to match the mood and theme of any public art installation.

 

solar light for public art 

Another important advantage of solar lights is their durability, particularly for outdoor public art projects. Reputable solar lights are made to resist inclement weather, such as rain, snow, and extremely high or low temperatures. This maintains the integrity of the art installation by guaranteeing that the lighting is dependable and operational throughout the year. Additionally, solar lights use less energy, which lowers carbon emissions and satisfies the growing need for environmentally friendly lighting in public areas.

 

SLD, Solar Lights Do, is a reliable partner for anyone wishing to include solar lighting in their upcoming public art project. With a focus on producing and marketing premium solar lights, SLD provides a large selection of long-lasting and effective outdoor solar lighting options. If you are interested, visit www.solarlightsdo.com and discover how SLD can help bring your artistic vision to life.

Solar Lighting Solutions for Commercial Signage

Businesses rely on clear, visible signage to attract customers, especially after dark. Installing and maintaining traditional lighting systems can be difficult due to their complicated wiring and high energy expenses. Outdoor LED solar light that runs on solar power provide a useful and affordable substitute for grid electricity, guaranteeing steady and bright illumination.

 

In order to power LED lights at night, solar powered lighting converts daylight into electrical energy. By doing away with the necessity for subterranean wiring, this self-sustaining system lowers installation and ongoing electrical expenditures. Modern solar sign lights, made possible by developments in solar technology, offer strong brightness and a long runtime, ensuring that signage is visible all night long.

 

solar powered lighting

 

Businesses signs are always illuminated thanks to long-lasting solar lighting systems that are made to endure a variety of weather situations, such as intense rain, snowfall, and extremely high or low temperatures. Among these solutions, the solar waterproof spotlight stands out as a reliable choice for ensuring consistent brightness and durability for businesses signs. In order to provide smooth operation with little effort, several versions also have automatic sensors that switch the lights on at dusk and off at dawn, making them an energy-efficient and hassle-free option for businesses.

 

In addition to being a wise financial move, switching to solar illumination is also an environmentally conscious one. Businesses may support sustainability initiatives while preserving a polished and well-lit image by reducing their dependency on conventional energy sources, which also helps to reduce carbon emissions.

 

SLD, Solar Lights Do, provides high-quality solar lighting solutions designed for commercial signage. Our products combine efficiency, durability, and ease of installation, making them an ideal choice for businesses looking to enhance visibility while reducing energy costs. Please explore our range at www.solarlightsdo.com.

Advantages of Half-Cut Cell Solar PV Panels

How do half-cut solar cells work?

Half-cut solar cell technology increases the energy output of solar panels by reducing the size of the cells, so more can fit on the panel. The panel is then split in half so the top operates independently of the bottom, which means more energy is created – even if one half is shaded.

That’s the general overview – below, we break the process down.

Traditional monocrystalline solar panels usually have 60 to 72 solar cells, so when those cells are cut in half, the number of cells increases. Half-cut panels have 120 to 144 cells and are usually made with PERC technology, which offers higher module efficiency.

The cells are cut in half, very delicately, with a laser. By cutting these cells in half, the current within the cells is also halved, which essentially means that resistive losses from traveling energy via current are reduced, which, in turn, equals better performance.

Since the solar cells are cut in half, and are thereby reduced in size, they have more cells on the panel than traditional panels do. The panel itself is then split in half so that the top and bottom portions operate as two separate panels – generating energy even if one half is shaded.

The key to half-cut cell design is a different method of “series wiring” for the panel, or the way the solar cells are wired together and pass electricity through a bypass diode within a panel. The bypass diode, indicated by the red line in the images below, carries the electricity that the cells generate to the junction box.

In a traditional panel, when one cell is shaded or faulty and does not process energy, the entire row that is within the series wiring will stop producing power.

For example, let’s take a look at the traditional 3-string series wiring method:

With the traditional full cell string series wiring, shown above, if a solar cell in Row 1 does not have ample sunlight, every cell within that series will not produce energy. This knocks out a third of the panel.

A half-cut, 6-string solar panel works a bit differently:

If a solar cell in Row 1 is shaded, the cells within that row (and that row only) will stop producing power. Row 4 will continue to produce power, generating more energy than a traditional series wiring because only one-sixth of the panel has stopped producing power, instead of one-third.

You can also see that the panel itself is split in half, so there are 6 total cell groups instead of 3. The bypass diode connects in the middle of the panel, instead of on one side like the traditional wiring above.

What are the advantages of half-cut cells?

The advantages of half-cut cell panels are numerous.

They improve the power output and performance of solar modules because they offer a higher shade tolerance due to their unique wiring system. This means that if your home has some trees that cast shade onto your roof at certain times during the day, your entire solar panel will not be unusable, like it would with a traditional solar panel.

Another benefit is the fact that they usually offer a higher wattage than traditional panels, meaning they produce more power per square foot.

Additionally, the effects of hot spots are less severe on your solar panels with half-cut cells. Hot spots are the shifting of excess heat on a panel, say from a very hot part to the shaded, cooler section. With a half-cut cell, hot spots will not be as damaging because there are more cells to spread the excess heat to.

Half-cut cells also reduce power loss suffered by traditional panels by reducing internal resistance. Internal series resistance occurs just by the nature of energy traveling through the panel via electric current. But because solar cells are cut in half, there is less current generated from each cell, meaning less resistive losses.

HJT or TOPCon? Which technology of N-Type Solar Cell will replace PERC?

Amid constant iteration in high-efficiency solar cell technology, domestic businesses have exceeded 23% in the efficiency of mass production at new PERC production lines in 2021, and managed to develop ceilings at an efficiency of almost 24%, which further solidifies the determination of domestic businesses in establishing additional production lines for the N-type solar cell.

N-type cells that have so far achieved a small-scale mass production (>1GW) include TOPCon, HJT, and IBC. According to the analysis of EnergyTrend, the capacity and market share of N-type cells started to elevate simultaneously since 2021, where the capacity of N-type cells is expected to arrive at 22GW at the end of 2021, while the market share is estimated to surpass 10% in 2023.

First-tier module makers have confirmed the deployment of N-type technology for 2021. In terms of product arrangement, Canadian Solar and Trina Solar are planning to sell HJT modules, while Longi and Hanwha are going to sell TOPCon solar modules. Jinko Solar has already started selling TOPCon module products, whereas Risen Energy plans to release module products that contain the technology of TOPCon and HJT. Pertaining to the establishment of production lines, Risen Energy has commenced the mass production on HJT modules, while CSI will be building a pilot scale production line for HJT, and JA Solar has completed the pilot scale production line for TOPCon before constructing the HJT production line scheduled for the second half of 2021. Jinko Solar has started the mass production for TOPCon modules, whereas the TOPCon cell factory of Longi is expected to go into operation in 2021.

Integrated businesses are focused on TOPCon, while the new capacity for N-type is centralized on HJT projects. The market arrangement for the TOPCon technology is primarily seen from integrated businesses such as Longi, Jinko Solar, and JA Solar right now. Most businesses have preserved space for TOPCon upgrades in their new PERC capacity since 2020. Numerous businesses are engaged in the HJT technology, including professional cell businesses, module makers, equipment integrators, and new businesses. Among them, Risen Energy, Akcome, GS Solar, and Meyer Burger are all planning to establish GW-grade HJT projects.

Stability in Mass Production is Essential as Ceilings Constantly Rise for Efficiency

Judging by the current cell efficiency, Longi has achieved a conversion efficiency of 24.1% within the laboratory, which is almost the theoretical limit of 24.5% for PERC cells. PERC technology has officially entered the post-change cycle with cell businesses gradually shifting to new technology pertaining to the emphasis of R&D, while the industry is accelerating on the approval of pilot and mass production lines for TOPCon, HJT, and IBC, so as to actuate the laboratory efficiency of the N-type cells to over 25%.

Differences in Conversion Rate are starting to expand between N-type cell and PERC. According to the latest progress announced by businesses, N-type HJT, TOPCon, and the existing PERC have respectively arrived at 25%, 24.5%, and 23.5% (Tongwei) in terms of the highest mass production conversion efficiency. In addition, an enormous level of investment from businesses was injected into N-type cells, which prompted the imminent mass production of TOPCon cells, and multiple businesses are making smooth progress in the pilot production lines of HJT, before marching towards GW-grade production.

N-type cells are still climbing in the efficiency of mass production, with stability yet to improve further. However, it is evident that N-type HBC and tandem cell technologies are also in the midst of the R&D phase, with further room for improvement in terms of the conversion efficiency.

Cost Becomes an Essential Factor for the Simultaneous Advancement of TOPCon and HJT

The cost of wafers and slurry for N-type cells is yet to be optimized. Raw materials and production account for a higher ratio in the cost structure for HJT cells, and the former is largely occupied by wafers and silver paste. HJT consists of 50% a-Si cost, and the reduction of a-Si cost has become an important direction in lowering the cost of HJT. The cost per watt for TOPCon cells comprises of wafer, silver paste, and depreciation, which account for 62.5%, 15.8%, and 3.7% of the respective cost, and the decrement of future cost primarily comes from wafer thinning, consumption of silver paste, and cost reduction in equipment.

Most of the early production lines for N-type cells had adopted overseas equipment that are higher in cost, and an increasing number of fully localized production lines will be seen alongside the constant maturity of local equipment. A fully localized production line appeared from the tender of four 1GW production lines by Tongwei in 2020, and the debugging statistics for the four production lines are expected to be announced in 2021. The localization trend in the production lines and equipment for HJT cells is becoming evident. Regarding the cost of localized equipment, Shenzhen SC aims to achieve a conversion efficiency of 25% for HJT in 2021, and lower the investment for a single GW-grade equipment to RMB 350 million, which may help with the preliminary establishment of a new structure for the market of N-type cell equipment.

As pointed out by the analysis of EnergyTrend, the current yield rate of PERC cells is at more than 98%, and the lack of maturity for TOPCon and HJT cells on major technologies has become the primary constraint to the exiting development of N-type cells, while the trend of large-sized cells also further extends the lifespan of the PERC technology that possesses a higher degree of maturity. The mass production of N-type cells will remain focused on G1 and M6 in 2021, and the industrialization of N-type cells in the future would have to resolve issues, including the higher cost, efficiency and stability of mass production, and the challenges imposed by the yield rate, under the revolution of M10, G12, or wafers of larger sizes.

 

 

How Bifacial Solar Panels Can Increase Power Generation?

In the race to develop the most efficient type of solar panels, manufacturers have developed bifacial solar panels. This type of panel has solar cells on both sides which allows the technology to capture more sunlight leading to greater solar cell efficiency compared to traditional solar arrays.

How Do Bifacial Solar Panels Work?
Lets first dig deep into how bifacial solar panels function. The top and bottom solar cells on a bifacial solar array function differently. The top solar cells function like a conventional solar panel array. They face the sun, so they capture incident sun rays directly, absorbing only certain wavelengths.

On the other hand, the bottom solar cells absorb light that is reflected off the ground. Since white or light colors reflect better than dark colors, painting a white or silver surface on the roof or driveway under the panels is encouraged. According to a study by Burns & McDonnell, white surfaces reflect more than 80% of this light while grass only reflects 23%.

How Is Bifacial Solar Panels Installed to Increase Efficiency?
To understand the difference, let’s first uncover how a monofacial solar array is set up. A monofacial solar panel system, or a group of one-sided solar panels, are placed in racks parallel to a surface such as a rooftop. Unlike single-sided panels, bifacial solar panels are installed on a tilt because they produce more energy when they are angled off of the roof or ground at varying degrees.

Below are three benefits of the titled installment of the bifacial solar array.

1. More sunlight to absorb
In these types of titled installations, there is a great amount of reflection. Because sunlight bounces off of all objects reflectively at many different angles, bifacial solar panels are able to capture more of it.

2. Productive on cloudy days
Because of the point above, bifacials can be productive on cloudy days while monofacial solar cells are at a greater disadvantage when there isn’t direct sunlight. Also, bifacials are less susceptible to weather damage because they are more durable. According to the Solar Magazine, because they are more durable than conventional solar panel systems, warranties for bifacial solar panels are typically 5+ years longer (that is, 30+ years versus 20–25 years).

3. Two energy peaks a day
A titled installation can also produce two energy peaks throughout the day based on their placement. For example, half of the bifacials in an array can be tilted toward the east to capture sunrise and morning rays. The second half can then be tilted to the west to soak up afternoon intensity and sunset rays.

Another installation that can achieve this is a vertical installation. During each peak, the reflection of sunlight on the other side of the solar panels will also contribute to energy production.

How Much More Efficient is a Bifacial Solar Array?
When we say efficiency, we are referring to how a solar cell takes the amount of solar energy it received and converts it into electrical energy. Although bifacials produce more electricity than monofacial panels, it definitely isn’t double the efficiency although solar panel manufacturers are working to make that happen in the future. Bifacials can increase energy efficiency by 11% compared to a conventional solar panel system, according to our study. And with a solar tracking system that tilts solar cells continuously toward the sun, the bifacial solar cell efficiency can be as high as 27%.

How does Floating Solar Power System work?

Introduction

Floating solar farms gained traction in 2018, particularly in countries with high population density and with competing uses for limited available land. These also operate at high efficiency since installing the solar panels on water helps cool the equipment.

The Republic of Korea was among the first to pilot floating photovoltaic (PV) systems. State-owned Korea Water Resources Corporation (K-water) began testing a 2.4-kilowatt (kW) model in 2009 on the surface of Juam Dam reservoir in Suncheon, South Jeolla Province. In October 2012, it constructed a 500-kW commercial plant at the Hapcheon Dam in South Gyeongsang Province after it developed a 100-kW demonstration plant in Hapcheon Dam the year before. This was the world’s first commercial floating solar PV installation using the surface of a dam reservoir and the country’s first floating solar farm.

The country currently operates three commercial floating solar power facilities that aim to contribute toward increasing the share of renewables to 20% of the energy mix by 2030 from the current level of 7%.

What is a floating solar photovoltaic system?

It is an eco-friendly method of generating electric power that combines marine technology and renewable energy technology. Solar modules are made to float on the surface of water, such as a dam or a reservoir. Electricity is sent through underwater cables to a transmission tower.

Figure 1: Floating PV Generation Concept

Source: K-Water

What are the benefits of a floating PV system?

  • Promotes land-use efficiency. As the floating PV energy systems are set up on water, the land can be used for other purposes. It requires no construction on land or conversion of forest and farmlands for solar power facilities.
  • Provides high-energy yield. The increased energy generation is due to the natural cooling effect of the water, which reduces rises in temperature of the solar modules.
  • Saves water resources. It reduces the evaporation of water in the reservoir since the floating PV system blocks the sunlight.
  • Uses an eco-friendly system. Natural fish farms thrive under the platform.

Four environmental impact analyses by the Korea Environmental Policy and Evaluation Institute (KEI) from 2011 to 2019, showed that the floating PV facilities caused no harm to the environment, developed a ground for fish spawning, increased aquatic plants, and reduced algae. Also, as of 2018, the floating solar farms in the country has reduced the amount of carbon emissions by 52,414 tons.

What are its features?

A floating solar power plant is composed of the solar module, buoyancy body, and anti-rust material, which includes the vertical frame and horizontal frames, inspection footrest, and module mount assembly.

The solar module should be highly resistant to humidity, lead-free, dust-proof, and protected against the effects of temporary jets of water, and it should have passed the drinking water test. Floating PV Mounting System is applied to solar pv power plant installation on the water. Adopting HDPE material, it should pass the Hunt Water Absorption Test, Anti-Aging Test, Anti-UV Test etc. Moreover, it can bear the pulling force that is much higher than other products. Adopting new module design in floater and main floater, it can realize the array of double row in the same facing or in symmetrical facing, which can increase the efficiency of solar power generation and installation capacity, be easily installed, and save the cost. and its lifetime has more than 25 years.

Figure 2: Floating PV Plant Components

SunEvo Solar Floating System

Introduction of IEC Standard Testing for Photovoltaic Solar Panels

Solar panel testing and certifications

Like other types of electronics, solar panel modules go through rigorous testing before installation. These tests are critical to determining the quality and performance of panels under particular environmental stresses, as well as confirming they meet mandated safety requirements. In this article, we’ll review the most common testing and certifications for solar panels on the market today.

Why is solar panel testing important?

Solar panel testing is key to assuring both the quality and safety of a module. Photovoltaic Solar Panels have a long lifespan: properly built and installed equipment should generate usable electricity for more than 25 years. Given the longevity of your investment, you want to make sure that any equipment on your roof will perform well and operate safely on your roof.

With solar becoming more and more popular each day, many states, local governments, and utility companies have come out with new mandates that require any grid-tied solar equipment to hold specific certifications. The same holds true for some solar incentive programs; if you’re participating in a state-funded incentive program, don’t be surprised if they have certain testing or certification requirements for your chosen equipment.

Common solar panel testing & certification standards

While reviewing a solar panel spec sheet, you’ll likely notice a bunch of acronyms and random numbers listed under safety and rating certifications – what do these mean? Below are some of the most common solar panel testing standards and certifications to look for when comparing solar panels:

IEC: International Electrotechnical Commission
The IEC is a nonprofit that establishes international assessment standards for a bunch of electronic devices, including photovoltaic (PV) panels. Importantly, the IEC does not test or certify panels themselves – they establish the standards for other testing facilities to adhere to when evaluating solar panel quality.

IEC 61215: Standards for crystalline silicon terrestrial PV modules
IEC 61215 is one of the core testing standards for residential solar panels. If a solar panel module successfully meets IEC 61215 standards, that means it completed a number of stress tests and performed well in regards to quality, performance, and safety.

IEC 61215 standards apply to both monocrystalline and polycrystalline PV modules, which are the most common types of solar panels. The IEC sets different testing standards for other types of solar electric technologies, such as thin-film solar products (IEC 61646).

Solar panels that meet IEC 61215 standards are tested on the following (and more!):

Electrical characteristics (wet leakage current, insulation resistance)
Mechanical load test (wind and snow)
Climate tests (hot spots, UV exposure, humidity-freeze, damp heat, hail impact, outdoor exposure)
IEC 61215 tests also help determine a panel’s performance metrics at standard test conditions (STC), including temperature coefficient, open-circuit voltage, and maximum power output.

What are Standard Test Conditions (STC)?
When solar panels undergo performance testing, they do so at fixed laboratory conditions, known as Standard Test Conditions (STC). Because these conditions are the same across the industry, one panel’s performance metrics (such as power rating, module efficiency, optimal voltage, etc.) can be compared apples-to-apples against other available options.

IEC 61730: Standard for PV module safety
As with any electronic device, solar panels carry the risk of electrical shock if improperly built. That’s where IEC 61730 comes in: this standard address the safety aspects of a solar panel, encompassing both an assessment of the module’s construction and the testing requirements to evaluate electrical, mechanical, thermal, and fire safety. PV modules that successfully pass IEC 61730 tests run a low risk for these types of hazards.

IEC 62716: Ammonia corrosion testing of photovoltaic (PV) modules ammonia corrosion
Do you live on or close by to a farm? If so, keep an eye out for IEC 62716 – this is a test to determine a module’s resistance to ammonia. While most people don’t have to worry about their high concentrations of ammonia exposure with their PV modules, it can be a concern if you install your solar panel system close to farms and livestock. Ammonia corrosion can accelerate degradation in a panel, leading to lower overall electricity production over the lifetime of your system.

IEC 61701: Salt mist corrosion testing
If you’re lucky enough to be installing solar panels on a beach house, it’s worth checking to see your prospective solar panels have successfully passed IEC 61701 tests. With these tests, panels undergo a series of salt sprays in a controlled environment. After the sprays, testers inspect the modules for physical damage – such as corrosion or delamination– and assess their electrical output and overall performance. Panels that successfully pass IEC 61701 tests are definitely a suitable choice for beach-front solar panel systems or systems that will be in close proximity to roads experiencing high levels of salting in the winter.

IEC 60068-2-68: Blowing sand resistance testing
Some solar panels go through IEC 60068-2-68 testing to determine how well they hold up in sandy desert environments. Frequent exposure to abrasive sand can wear a panel down, leading to physical or mechanical defects over time. If you’re installing solar in an area that sees frequent sand or dust storms, try choosing a panel that successfully passed these tests to maximize the durability of your system.

UL: Underwriters Laboratories
Outside of IEC, the other most common acronym you’ll see on a spec sheet related to solar panel testing is UL. This stands for Underwriters Laboratories (UL), a global safety certification company based in the United States. They provide testing services and certifications for many different types of products, including electric appliances, industrial equipment, plastic materials, and more.

UL 1703: Standard for flat-plate PV modules and panels
UL 1703 is an industry-standard attesting to both the safety and performance of solar panel modules. Similarly to IEC 61215 or 61703 tests, panels with this certification go through simulated climatic and aging tests and have been deemed as safe in regards to mechanical loads, fire, and electrical hazards.

You may find that a solar panel spec sheet lists both UL 1703 and IEC 61730 under safety certifications; this is pretty typical for any solar panel sold worldwide. UL 1703 is a mandate for solar panels sold and installed in North America. IEC 61730, on the other hand, is internationally recognized for safety standards and is more widely applicable to the global solar market.

UL 61730: Photovoltaic module safety qualification
UL 61730, a more recent addition to solar panel testing and certifications, combines the testing procedures and standards of UL 1703 with IEC 61730, allowing for complete international approval in regards to a panel module’s safety and performance.

It will become more and more common to see this certification over time–as opposed to both UL and IEC–because it is often the more cost-effective option for manufacturers. In order to complete solar panel testing, manufacturers need to provide multiple solar panel samples. For companies that plan to sell in both North America and international markets, solely completing UL 61730 testing reduces the number of panel samples needed, allowing for reductions in testing time and costs.

New Record! HJT Solar Cell Efficiency reach 25.23%!

 

The 166mm monocrystalline HJT solar cell developed by SunEvo has achieved a record-breaking conversion efficiency of 25.23% from the recent testing of the authoritative testing institution ISFH, which means SunEvo’s sturdy improvement in HJT solar cell technology, and indicates the company’s unswerving determination and strength in achieving the particular efficiency.

It is understood that SunEvo had achieved a conversion efficiency of 25.06% for the mass production line of 166 HJT solar PV cell on June 8th, before achieving a new world record of 25.23% by adopting the microcrystalline production process when working with leading HJT equipment supplier Maxwell. According to Doctor Wang, the CTO of SunEvo, the record is a new height achieved on microcrystalline craftsmanship that is possible for mass production, as well as a reliable guarantee in attaining a mass production efficiency of 25.5%.

Senior insiders of the industry commented that the regular-sized 166mm Champion cell announced by SunEvo still uses the sputtering TCO film for the PVD mass production process, which offers feasibility in extensive mass production, while the difficulty and gold content are self-evident. The company has been aggressively exploring methods in elevating efficiency and reducing cost, and achieved constant improvement in mere months, as well as multiple critical breakthroughs in N type high-efficiency mono-Si HJT solar cell technology.

Doctor Wang commented that HJT solar cells can be further improved in efficiency by replacing the current doped amorphous silicon with doped microcrystalline silicon or doped microcrystalline silicon oxide (carbide), where both the doping concentration and light transmittance would elevate, and the electrical resistance of the doped layer would reduce, before the current density of the HJT cell is magnified at the end. Doctor Wang said that the company anticipates a constantly improving record of efficiency, and these high-efficiency technologies will be applied on the production lines to achieve extensive production under low cost and applications for GW-grade 25%+ HJT cells.

HJT still possesses a relatively large sum of impedances and difficulties in progression after 30 years of development since 1990; thus, a reinforcement in the guidance and innovation of leading companies are exceedingly important in the expedition of commercial applications of HJT, as well as the actuation of technical upgrades in the relevant equipment and materials of the supply chain. On the occasion of HJT’s 30th anniversary, the Shanghai Solar Energy Society and the TestPV Forum will once again convene the “6th International Forum for the Leading Mass Production and Supply Chain Coordination of HJT”, which centralizes global businesses and experts from the research, manufacturing, application, and investment fields of solar cells, as well as comprehensively probes into the technology and popular market topics of each segment of the HJT industry chain, and penetrates into the future development orientation of HJT cells.

 

 

Trends of Solar PV Cells and modules – 166mm, 182mm or 210mm?

 

For more than ten years, the classic solar module with a cell size of 156 mm (M0 wafer), later 156.75 mm (M2 wafer), was considered as the standard solar PV module and was very popular.

The times when solar module dimensions have remained on the market over a longer period of time and could be established as a standard are now over. This became particularly noticeable at the beginning of 2020 when solar module producers from China started the trend towards ever larger solar module formats. Increasing wafer sizes are responsible for this.

Solar Cell Size SunEvo

 

Wafer sizes get bigger and bigger

 

As recently as 2018, 156.75 mm wafers accounted for about 80% of the market. In 2020, the upheaval came to 158.75 mm wafer sizes. The module outputs here range between 325 and 345 watts, and the dimensions are about 10 to 30 millimeters larger than a classic 60-cells PV module, depending on the design – so they are still very easy to move and process. However, the 158.75 mm solar cell, which was introduced only a few years ago, is already only available to a very limited extent.

Global Market Shares of Wafers by Size SunEvo

Global Market Shares of Wafers by Size

A new size came onto the module market – M6 wafers with 166mm. In 2021, it turns out that this size has become the most widely installed solar module. This is a 120 cell with typically 350 to 380 watts solar panel.

But there seems to be no end in sight. The trend shows that it is possible to go even bigger. Wafer sizes of 182 mm (M10) and 210 mm (M12) have now arrived on the market. With the new cell sizes, a new power class is also emerging: M10-based modules have between 545 and 560 Wp Solar Panel.

 

 

According to the leading companies, modules with 182 mm wafers and 210 mm wafers are clearly superior to modules with smaller wafers in terms of manufacturing costs. Therefore, modules with these wafer sizes will probably prevail in the long term and make up the majority from 2022/2023.

Installers will also have to deal with this development. On the one hand, a certain increase in efficiency can usually be provided with the use of larger dimensions. On the other hand, handling according to the manufacturer’s installation instructions is only one aspect that must be considered. Larger module areas set new requirements for the module installation and the substructure, which may have to be planned and executed completely differently, with the same or lower frame thickness.

 

 

Types of Solar Trackers and their Advantages & Disadvantages

Types of Solar Trackers and their Advantages & Disadvantages

Solar trackers are a type of device with photovoltaic (PV) panels, which accurately tracks the path of the Sun throughout the day. Typically, a solar tracking system adjusts the face of the solar panel or reflective surfaces to follow the movement of the Sun. The movement of solar trackers increases the solar energy output by up to 40% than standard panels. Solar trackers are increasingly used in both residential and commercial-grade solar panels due to improved and more efficient solar trapping technology.

Types of Solar Tracking Systems

Solar tracking systems can be classified by the mode of their motion.

There are axes for a moving surface: two horizontal axes and one vertical axis.

The surface can be rotated around each axis (tilted) to get the right angle for receiving the maximum sunlight.

When movement or adjustment of the surface happens by rotating around one axis, it is called single-axis tracking.

On the other hand, when the rotation of the surface happens around two axes simultaneously, it is called dual-axis tracking.

Application of Single-Axis Tracking System

 
 

Single-axis trackers usually move from the east to the west and follow the Sun’s direction.

Single-axis trackers have only one angle that is used as the axis of rotation. This type of tracker can increase electricity production by more than 30%.

These trackers provide an efficient, simple, and low-cost way to improve the functioning of solar installations.

Also, these trackers can optimize the performance of the Sun during the summer and spring seasons, when the Sun is in a higher position in the sky.

The usefulness of single-axis trackers, however, drops as they move farther towards the North. It is because the variance of the solar angle is higher between the summer and winter seasons.

Also, the performance drops during the other times of the year for the horizontal position of the Sun. At higher latitudes, vertical axis trackers work better.

This way, solar arrays or panels can track the position of the Sun during winter as well as summer.

Now, let us talk about different types of single-axis trackers such as horizontal, vertical, tilted, and polar aligned.

Horizontal Single-Axis Solar Tracker (HSAT)

Horizontal single-axis solar tracker rotates from east to west throughout the day on a fixed axis which is parallel to the ground.

This type of tracker is considered the most cost-effective tracker geometry in many applications.

Single-axis horizontal trackers can follow the Sun’s movement from the morning to evening across the sky.

An HSAT structure may be supported at many points along the rotating axis and therefore requires less complexity and less material for construction than other tracking geometries.

The horizontal tracking geometry is more preferred as it reduces the structural material requirements by keeping the modules at a relatively low profile to the foundation.

Also, no special connection is needed to rotate the system about its center of gravity.

Horizontal Tilted Single-Axis Solar Tracker (HTSAT)

This type of single-axis solar tracker is similar to the HSAT. However, the device is installed at a certain tilt.

Tilted-axis tracking systems are relatively more complex than horizontal single-axis trackers and usually require a concrete foundation.

HTSATs are tilted upward and toward the south or the northern hemisphere and rotate the panels from east to west throughout the day to track the Sun’s movement.

Because HTSATs are more complex, they may be expensive. Also, the potential requirement to have a concrete foundation adds up cost.

Generally, HTSATs is not scalable, which means the mechanical components are not shared between units. Due to this, the cost per panel may not be lower in larger arrays.

Vertical Single-Axis Solar Tracker (VSAT)

Vertical single-axis solar trackers or VSATs rotate from east to west following the Sun throughout the day.

These systems are often installed in high-altitude or mountainous locations.

The profile of VSATs is not parallel to the ground, because of which it is easier for these trackers to maintain a consistent angle of solar incidence when the Sun is lower in the sky.

This is particularly beneficial in northern latitudes, for example, between 40° and 55°. However, unlike planar horizontal arrays, vertical field layouts need to accommodate the taller profile of the vertical tracker and spread units out to avoid self-shading and energy losses.

As a result, vertical single-axis trackers tend to have a relatively lower power density per acre.

Vertical-Tilted Single-Axis Solar Tracker (VTSAT)

This type of tracker is similar to a horizontal, tilted single-axis tracker. The only difference is that the tilt is parallel to a horizontal position and rotates on a vertical axis.

These trackers can also improve energy harvest compared to horizontal trackers. However, due to the optimal tilt angle, the tilted single-axis trackers are subject to increased wind loading compared to horizontal units.

In VTSTATs, structural requirements are higher, and as a result, more steel and concrete are used compared to a horizontal array.

Advantages of Single-Axis Solar Tracking System

Single-axis trackers have a single degree of flexibility that serves as an axis of rotation, which is generally aligned along a North-South path. Major advantages of single-axis trackers include:

  • Single-axis trackers are more reliable.
  • Single-axis has a longer lifespan than dual-axis trackers.
  • Single-axis trackers are cheaper than dual-axis trackers because they have a simple mechanism and operate at a low cost.
  • Single-axis trackers are ideal for companies with a lower budget or generally cloudy areas.
  • Single-axis trackers are nearly 32.17% efficient compared to a fixed solar tracker mount panel.
  • These trackers follow the Sun from East to West, providing consistent power output all day long.
  • The trackers generate 15-16% higher annual power as compared to a static station of the same installed capacity.
  • Single-axis trackers provide the highest density of PV panel placement per square.
  • The payback period is lesser for the investment of the solar project, and a significant increase in profits.

Installation of a solar tracking system may require some additional parts and gears to add to the solar panel system, and they require maintenance from time to time as well.

Disadvantages of Single-Axis Solar Tracking System

  • Energy output is lower by single-axis tracker during sunny conditions compared to dual-axis trackers
  • Limited technological upgrade.

Application of Dual-Axis Solar Tracking System

 

Dual-axis trackers have two rotation axis degrees, which are called the “primary axis” and the “secondary axis.”

The rotational axis can move downwards or upwards to adjust with the angles of the Sun throughout the day.

Dual-axis tracking allows for the most accurate orientation of the solar device and is said to provide 40% more output through energy absorption. However, these solar trackers are more complex and expensive.

Dual-axis trackers continually face the Sun as they can move in two different directions. There are two types of altitude-based dual-axis trackers — tip-tilt and azimuth-altitude.

Typically, dual-axis tracking is used to orient a mirror and redirect sunlight along a fixed axis towards a stationary receiver.

As these trackers track the sun’s path vertically and horizontally, they help obtain maximum solar energy.

Azimuth-altitude dual-axis trackers can solve both issues. However, these trackers can be expensive and add nearly $3,500–$6,500 to the solar installation cost.

The function of dual-axis trackers depends on vertical and horizontal pivots, which are controller-guided similar to solar telescopes. These are quite costly, and their usage is generally limited to solar energy systems of commercial grade.

The accurate tracking of dual-axis solar trackers is also used in a focused solar application, such as mirrors that direct sunlight receivers and convert sunlight into heat.

Advantages of the Dual-Axis Solar Tracking System

  • Dual-axis trackers follow the Sun continually and provide constant power output throughout the day.
  • These solar trackers provide a reasonable solution in cases of the limited power capacity of the connection to the grid.
  • Dual-axis trackers need smaller space and provide an opportunity to use the remaining area around for other additional purposes such as car parking, gardening, and others.
  • These trackers generate 45-50% higher power output per year, as compared to a static station of the same installed capacity;
  • Dual-axis trackers provide the optimal solution for areas that may hinder solar productivity. Some of these areas could be a complicated structure of the ground, complicated relief, stone protrusions, descent towards the North, and others.
  • The payback period on investment is lower in the case of dual-axis trackers.Also, there will be a significant increase in profits during their lifespan.

Disadvantages of Dual-Axis Tracker

  • Dual-axis trackers have higher technical complexity, which makes it potentially vulnerable to glitches.
  • These trackers have a shorter lifespan and lesser reliability.
  • Low performance in cloudy or overcast weather

Other Types of Solar Trackers:

Passive Trackers

Passive solar trackers use a compressed gas fluid with a low boiling point that rotates to one side or the other to make the tracker move in response to an imbalance.

As this type of orientation is not precise, it is not suitable for certain types of concentrating photovoltaic (PV) collectors but works fine for common PV panel types.

Active Trackers

Active trackers, on the other hand, use motors and gear to direct the tracker by a controller, responding to the solar direction.

Because the motors consume energy, they need to be used when it is necessary.

The Future Scope of Solar Tracking Systems


Solar trackers, be it single-axis or dual-axis, can help generate the optimum level of solar power.

This is why it is important to decide which type of tracker is suitable considering various factors, including the terrain, climate, and the type of solar panels that are being used.

If you are a solar installer, depending on the budgetary constraints of your client, the terrain and climate, and the lifespan of the system, you need to consider the key factors to make the right decision.

Now, when it comes to the future of the solar tracker industry, it seems pretty bright. In 2018, the estimated size of the global solar tracker market was $2.92 billion, according to the Grand View Research.

The market is expected to expand at a CAGR of 14.1% by 2025 due to the growing demand for solar cells or photovoltaic cells. This growth rate is expected to continue in the coming years.