Granville, N.Y. — The photovoltaic (PV) industry is expected to grow exponentially over the next five years with market experts anticipating the global market to more than double in size by 2014. While this impressive growth rate is good news for the PV industry as a whole, module manufacturers are faced with a unique challenge — how to meet increased demand, while remaining profitable. In order to remain competitive and take advantage of industry growth, module manufacturers need to take steps to enhance overall production efficiency, reducing cost-per-unit. Automating production lines, reducing material waste, and decreasing equipment downtime are three ways module manufacturers can increase throughput, as well as their bottom line.
The Speed of Automation
Before solar power was considered a viable source of energy, module manufacturing plants with 100 MW of capacity were considered large. Today, as module manufacturers strive to meet the growing market demand for solar products around the world, facilities are expanding and we are seeing manufacturing plants with annual manufacturing capacity of 300 MW and more. This higher level of capacity has created the need to increase production efficiency and automated processes are becoming standard.
One key area where automation can help manufacturers increase overall productivity is manufacturing speed. By maximizing output for each step in the production process, automation enables increased capacity, while eliminating the need for additional investment in continuous plant expansion in order to meet ever-increasing demand.
By eliminating human error, automated production lines offer an increased level of accuracy, ensuring a consistently high-quality final product. Automation also reduces the need for manpower, further reducing manufacturing costs.
Frame tape applications are a good example of how automation can provide benefits on a PV module production line. Frame tapes are used to secure the solar module into the metal frame to ensure the mechanical load requirements of the IEC standards are satisfied. The application of frame tape plays a key role in ensuring consistent adhesion and centering the module into a frame. While smaller manufacturing operations might use hand applicator tools for the framing process, larger manufacturers need advanced solutions that can provide precision at high production speeds. Semi-automated taping equipment or fully automated robotic tape and framing stations offer increased production speeds to help manufacturers expand their capacity and maximise output while also reducing manpower costs.
For manufacturers on the lookout for new technologies that provide increased production efficiencies, a new generation of foamable sealants is now available. This curable thermosetting material is applied warm to provide instant adhesion in the framing process. High bond strength is achieved immediately after contact with the module glass, backsheet and frame, ensuring a consistent level of quality. Compared to conventional pumpable sealants, such as silicone, this new hybrid foamable frame sealant takes significantly less time to cure and eliminates clean-up time.
To further streamline the framing process, next generation single-piece framing systems offer an advanced solution for use with automated systems. The patented single-piece frame concept features a single continuous frame profile with corner notches cut in place to allow for wrapping around the solar module using a robot. The process allows framing to be done at very high speeds — less than 30 seconds per individual module — compared to traditional methods.
Making the Most of Valuable Resources
Wasted resources, be it materials, components or labour, can significantly affect a module manufacturer’s bottom line by increasing the unit cost per individual solar module. Each process within the manufacturing operation should be assessed carefully for waste reduction.
The process of framing solar modules, for example, provides significant opportunities for manufacturers to reduce production input. With conventional sealing methods, excess silicone overflows onto the module surface after the module is inserted into the frame and is wasted — an expense that could easily be avoided with a foamable sealant. This new technology allows optimum cavity fill to be achieved without any overflow, enabling the manufacturer to save on unnecessary material expenses, as well as man-hours spent cleaning.
Another way to reduce waste is by eliminating three of the four corner keys needed to frame a module. This is made possible using a single-piece framing system, reducing the material resources needed and the unit cost of each module.
Utilizing Existing Equipment
There are many ways for manufacturers to increase efficiency without investing in expensive additions or changes to the production line. One way is to maximise the service life of consumables used in the photovoltaic module-making process. Choosing products that offer longer service lives means equipment downtime can be kept to a minimum. This, in turn, leads to reduced costs as the frequency of purchasing new consumables is lowered.
The vacuum lamination process provides a prime example. Advances in silicone membrane formulations have led to the development of membranes that are highly resistant to EVA outgassing at high heat exposures, offering many savings for module manufacturers. Fewer membranes are required over a certain period of time, reducing the impact on purchasing logistics and lowering inventory requirements. In addition, the time required to change a membrane can vary between four to eight hours, presenting a bottleneck in the lamination process. By increasing the number of cycles per membrane, the laminator downtime can be significantly reduced. Avoiding the unnecessary costs of getting additional laminators online helps increase capacity and output from existing equipment, achieving optimal efficiency.
In order to remain competitive in the midst of the ongoing market growth, PV module manufacturers need to focus on enhanced production efficiencies, driving down overall manufacturing costs. Minor adjustments to photovoltaic module-making processes, such as utilizing automation technologies, choosing advanced materials and maximizing the service life of consumables, are ways for manufacturers to increase efficiency without having to invest in additional equipment.