By Chengjiang Fu, head of product and solutions, LONGi Solar North America
One of the biggest trends in solar modules is the arrival of large-format modules. The benefits of these mega modules have been widely reported, such as higher power ratings, reduced amount of balance of system (BOS) and electrical BOS components, lower installation costs and greater reliability. The combination of decreased capital expenditures, lower levelized cost of electricity and higher net-present value has excited utility-scale developers, EPCs and asset owners. But even with these benefits, big modules present some challenges.
One area that has not received as much attention is the shipping and handling of large-format modules as they make their way from the factories to the solar fields. Admittedly, module shipping, unpacking, handling and storing are not the sexiest topics — most of the industry’s attention goes to the installation process and related best practices — but for EPC site teams and other logistical partners, proper handling is essential. Some of the dos and don’ts are common sense, while others are not as obvious. With the arrival of the high-value, high-wattage modules, the time for buttoning up handling best practices has become even more urgent — since needlessly damaging hundreds of these modules comes at an even higher cost.
From factory to project site
Most solar modules travel thousands of miles from the manufacturing facility to the installation project site. Along the way, they are packaged, palleted, trucked, shipped on freighters and trucked again (and again). Module manufacturers have determined practical methods of crating and shipping large format modules to reduce the risk of damage along the way.
For example, horizontal or landscape-mode packaging of large-format M10 (182-mm cell) modules has been found to greatly reduce the risk of them falling over during transit, which could result in cell microcracking or other damage. Plus, this smart packing configuration conforms to standard 40-ft shipping container dimensions, maximizing the available space.
Because of supply chain disruptions over the past few years, the pressures on the logistics industry have grown, including a shortage of more than 80,000 experienced truck drivers and forklift operators, a need to optimize packaging materials and an uptick in issues with delivering modules safely to project sites. There have even been instances on large project sites where hundreds of modules in some shipments have been damaged, with many issues going unnoticed until after they are staged for installation.
Modules are loaded and unloaded many times along the way before finally being offloaded, unpacked and readied for installation. For the most part, millions of modules in various stages of transit make it to their ultimate destination in good shape. Yet after all that mileage, sometimes mishandling toward the end of the journey can lead to damaged or even broken modules.
Taking module handling seriously
Module manufacturers should work closely with both the freight carriers and their customers to mitigate the risks of module mishandling. Preinstallation training should be encouraged as well as the sharing of best practices to help ensure the safe unpacking, inspection, handling and installation of modules. Manufacturers should make available key documents to the relevant stakeholders to facilitate this, such as module installation manuals and unpacking, handling and storing guides.
Inspect on arrival
- Unusual loading method, shifted or tilted pallets
- Forklift damage on pallet with exposed modules
- Pallet wear and tear or damaged modules
- Unusual dents or scratches on the cardboard
If it’s discovered that the modules are damaged, best practices would recommend that the driver be informed immediately, as well as the carrier and module company staff within 24 hours of delivery. A record should be provided with detailed information within 48 hours of delivery. By doing this in a prompt and thorough manner, warranty headaches will likely be avoided.
Don’t stick a forklift in it
It’s surprising how much damage can be done when using forklifts to move module pallets. And the bigger the modules, the higher the potential risk. But with experienced operators and adherence to best practices, damage caused by forklifts can be avoided.
For example, the operators should use the right forklift forks, based on the pallet size, and never use oversized forks. The operator should always insert the fork from the short side of the pallet, as long as it is safe to do so. Issues with the forklift backrest are the most common cause of module damage. It’s recommended to use a backrest greater than or equal to 48 in. and never press the forklift backrest into the packaging cardboard.
Storing and staging
The proper onsite storing and staging of the pallets may seem like an obvious way to keep module damage to a minimum, yet it is sometimes overlooked. It’s best to stage the pallets in a flat, open and dry location when unpacking, and position the pallets next to a solid, self-standing support structure, such as a tracker post or wall — the taller and sturdier the better — where the modules can be leaned once they are removed from the packaging. And when it’s time to start moving the solar modules to be installed, always have two people lift and carry each module. This safety recommendation is imperative as the heavier, large-format modules—which weigh 70 to 80 lbs — become more prevalent at utility-scale project sites.
Keep in mind, the bigger and heavier the module, the more fatigue felt by the workers carrying them — make sure to schedule adequate rest and hydration breaks to ensure safe handling.