Printed circuit boards or PCBs are an essential part of any electronic equipment. With the prolific increase in the use of electronic devices in everyday life, PCBs now occupy a very important role in the control of environmental factors. For instance, each PCB contains many electronic components, metal tracks, solder, and several types of substrate materials. Using PCBs for landfill can allow its constituent metals and materials to leech into the soil, causing severe pollution. Therefore, there is an active movement to make Green PCBs that are beneficial to the environment. On the other hand, PCBs contribute to a substantial extent the move towards phasing out fossil fuel based energy systems in favor of renewable energy systems. According to PCB Trace Technologies Inc, it is necessary to understand this dual requirement for designing better PCBs.
With PCBs being increasingly in demand, it is necessary to know where they are useful. As the full list will be overwhelming, a comprehensive list where PCBs are in use is shown:
- Industrial equipment, including CAD/CAM systems and machine tools
- Computers and peripheral devices
- Smartphones, tablets, and wearables
- Televisions, augmented reality, virtual reality systems
- Medical equipment, diagnostic equipment, and robotic surgery devices
- Renewable energy systems like solar power, hydropower, and wind turbines
- Consumer electronics, including toys and entertainment systems
- Aircraft, drones, aerospace equipment for both commercial and military use
As it is obvious from the above list, there is significant contribution of PCBs not only to many technological advancements, but also to complex designs, thereby augmenting their reliability and functionality, and providing them with constantly shrinking footprints.
However, the expanding role of PCBs in various areas are also causing concerns related to their manufacturing processes, use, and safety factors from exposure, and eventual disposal of the boards. This concern is causing manufacturers and design engineers to turn to PCBs for renewable energy systems and towards green PCB design.
With the World showing increasing interest in renewable energy sources, the role of PCB technology in creation and use of renewable energy systems is significantly going up. Fabricators are now using advanced manufacturing techniques for PCBs. They are creating better prototypes and ultimately boards with higher quality and durability. This is leading not only to fewer defects in the field, but also to lower waste generation due to rejected boards. Advanced PCB design techniques are allowing designers to place additional components on boards, thereby reducing the number of physical PCBs necessary to meet design requirements, where earlier, they needed multiple boards.
For instance, modern PCBs are powering advanced monitoring equipment and control systems, thereby enabling environmentalists, water conservation groups, forestry services, and agronomists to track changes in climate and environmental conditions all over the world.
IRENA or the International Renewable Energy Agency has revised its target of doubling the consumption of renewable energy by 2030. Reliable and cost-effective PCBs will be playing a critical role in this direction through the use of solar, wind, and hydroelectric energy systems.
PCBs are making it possible to use LED lighting for reducing energy requirements. For instance, customized LED lighting panels are common in scoreboards, sports venues, advertising, storefront lighting, commercial displays, and much more. Highly technical and custom printed circuit boards are making all this possible. Innovative designers and manufacturers are offering sophisticated controls for these custom circuit boards. In contrast to the highly energy-intensive requirements of the older technologies, LED lighting offers very high-quality lighting options, thanks to high-technology PCBs.
The transportation industry is saving significant amounts of energy and money through the use of GPS or Global Positioning Systems. Here again, sophisticated printed circuit boards are allowing the GPS to provide the most effective route to a destination. In fact, PCBs are a huge contributor to the enormous energy savings that users of GPS technology are achieving, whether they are large freight carriers or individuals using GPS in their personal vehicles.
While Printed Circuit Boards are contributing enormously to the increasing use of renewable energy systems, manufacturers and designers are also working towards making the boards environmentally friendly. They are striving towards green printed circuit boards.
Like in any other manufacturing industry, manufacturers and fabricators of printed circuit boards are also subject to control specifications. These are typically mandated by geographic agencies. For instance, most manufacturers must comply with the RoHS or Restriction of Hazardous Substances directives. The RoHS directive specifically focuses on the restrictive use of materials known to be hazardous and fire retardants. In many places, there is a general restriction on the sale of electronic equipment that does not comply to the RoHS directives. With increasing adoption of such regulatory statutes such as RoHS and WEEE, there will be increasing awareness and adherence to green PCB design.
Device manufacturers and OEMs that use PCBs, are increasingly becoming more vigilant towards RoHS and WEEE compliance, both for boards they source from other providers or fabricate internally. Several other countries have different such guidelines. One of them is the REACH of the EU. It stands for the Registration, Evaluation, and Authorization of Chemicals. Similarly, Asian Pacific regions have their own initiatives.
The design of green printed circuit boards requires customization of fabrication processes, including the requirement for RoHS compliance and lead-free manufacturing. In this endeavor, PCB manufacturers are continuously working towards modern and newer techniques and materials. Their aim is to reduce the environmental impact significantly not only when manufacturing, but also when disposing printed circuit boards.
Unfortunately, the electronic industry impacts the earth’s environment in adverse ways. For instance, traditional PCB manufacturing uses many energy intensive and high-emission processes involving materials like copper, resin, epoxy, glass fiber, and water. After the lifecycle of a PCB has ended, it becomes a waste product.
Therefore, it is necessary to reverse the impact of electronics industry on the earth’s environment. Innovations in producing printed circuit boards that are environmentally friendly now range from additive processes to fully biodegradable boards.
While some processes work for limited runs of PCB production, the introduction of these innovative technologies offer greater promises for the future. For instance, some innovative methods are capable of recycling 90-98% of the copper from rejected and waste boards with the use of environmentally friendly etching chemicals that the existing subtractive processes use. However, there are other innovative processes as well.
Although the typical method of PCB production uses a subtractive process, many manufacturers are shifting to the additive printing process. The subtractive process is a multistep method that removes unwanted copper from the board by dissolving it using chemicals. In contrast, the additive printing process uses 3D printing electronics, aerosol and inkjet printing, conformal coatings, and direct wire production. In comparison to the subtractive method of removing unwanted material, the additive process only applies the requisite material.
A design team can use a PCB design software package to build the schematic and layouts. After ensuring that the work adheres to error checks and design rules, they can export the design to an MCAD and ECAD environment, and finally, send the finished design to a printer. This is typically a 3-D printer that prints the traces on the substrate. In contrast to the subtractive process, the additive processes do not require photomasks or etchants. This innovative design process works well for complex designs on thin substrates.
Some manufacturers have produced prototypes of paper-based multilayer PCBs. Using additive processes, they have successfully printed conductive materials on paper and fabric. Such paper PCBs offer significant environment benefits. The paper could offer the tensile strength necessary for supporting electronic components.
The manufacturers produced paper PCBs with five and ten layers of printed circuits using filled via connects. Conductive patterns made from silver particles retained the strength and bonded strongly to the paper substrate. The flexibility of the paper PCBs was adequate for the conductivity of the patterns, and these paper PCBs were cheaper than FR-4 boards.
Researchers have developed printed circuit boards made from natural fibers that they had extracted from agricultural co-products and wastes. In contrast to glass fiber and epoxy boards that are non-biodegradable, these bio-composite boards are fully biodegradable and harmless to the environment.
PCBs are a must for the electronics to function in renewable energy systems. But this equation works both ways. For the renewable energy systems to operate reliably, the PCBs must be likewise reliable and long-lasting. As renewable energy systems replace fossil fuel systems worldwide, PCB manufacturing is also tending towards using less energy-intensive processes. According to PCB Trace Technologies Inc, both, PCB manufacturing and the use of renewable energy systems are moving simultaneously towards making the electronics industry more environmental friendly.