Design for Sustainability with Printed Electronics

Governments around the globe are directly or indirectly addressing the aspect of sustainability, though in varying degree and intensity, not least in respect to recent inflation and international supply chain tariffs. They are calling upon manufacturers to reduce waste, energy consumption, chemicals, and their general environmental impact across the products' life cycle. 

The electronic product life cycle constitutes an industry that must handle toxic materials like lead, mercury, and cadmium. Hazardous materials that are flame retardant, and rare earth minerals such as lithium, cobalt and gold. The end result is over 53 million tonnes of electronic waste each year, with an estimated 17% to be formally recycled. 

The electronic industry has a traditional focus on subtractive manufacturing technology in regard to printed circuit boards, however by employing additive manufacturing technology there is a potential to significantly reduce waste, energy, eliminate hazardous materials, and improve recyclability. With tightening environmental regulations and a demand for greener alternatives, now can be the time to explore how printed electronics can align design and sustainability goals. Altium is strategically and actively supporting this development by engaging with its user base to improve and develop features to support electronic design for sustainability.

What Are Printed Electronics?

Printed electronics involve the use of printing techniques such as inkjet, screen, gravure, or flexographic printing to deposit materials onto flexible or rigid substrates. These materials can include conductive inks, semiconductive layers, and dielectric insulators, which work together to create circuits, sensors, antennas, and other electronic components.

These components are typically printed on substrates such as PET (polyethylene terephthalate), paper, or biodegradable polymers, enabling lightweight and flexible products with reduced material consumption. Applications range from wearable health monitors to flexible solar panels by enabling new form factors and applications. One of the key advantages of printed electronics is its inherent reduced environmental footprint, increasing the possibility for sustainable innovation.

Why Is Additive Versus Subtractive Manufacturing More Sustainable?

To understand this, one must examine the fundamental difference in manufacturing technologies, namely the additive versus the subtractive manufacturing process.

Subtractive manufacturing, which constitutes over 99% of conventional PCB manufacturing, begins with a solid material as a copper-clad FR4 (fiberglass-reinforced epoxy laminate). The desired circuit pattern is created by etching away excess copper using harsh chemicals like ferric chloride or ammonium persulfate. This generates large amounts of hazardous waste and chemicals that require water treatment and safe disposal. The relative design complexity of the PCB will consequently increase the number of layers or etching processes and this will further increase the sustainability impact of the electronic apparatus.

The process of additive manufacturing employed for printed electronics, builds up the circuitry by depositing materials only where it is needed. No etching, no stripping, no plating baths, but precision printing of functional inks directly onto a substrate, only added where it is needed. This significantly reduces the environmental footprint of the production process in several ways as described beneath.

Waste Reduction

Eliminating the need for chemical etching and plating, printed electronics reduce solid waste, liquid effluent, and airborne emissions. Conventional PCB production involves rinse stages, toxic metals, and heavy water usage, which contribute to both environmental and potential health hazards. Additive manufacturing can result in no material waste from cutting or etching, and no chemical baths.

Energy Efficiency

Printed electronics processes operate at lower temperatures and hence require less energy than subtractive PCB manufacturing, which involves high temperature lamination, different warm hazardous baths, curing, drilling, and plating. The evident result is a lower carbon footprint per unit produced. This makes printed electronics a compelling option for a company, which can employ the additive manufacturing technique for its products, industry standards, customer demands and governmental requirements.

No Plating

One of the major environmental negative drivers of PCB manufacturing is the electroplating process used to deposit metal onto circuit pathways or vias. This requires highly conductive electrolytes like copper, nickel, or gold and the process consumes large amounts of electricity.

Printed electronics naturally alleviates this process completely. Conductive traces are created directly with printed conductive inks as silver or carbon, at room or moderate temperatures. The elimination of plating simplifies production, reduces toxicity, enhances safety and requires significantly less operational space.

Electronic Life Cycle Management

End-of-life disposal and recycling of PCBs manufactured with the subtractive technology process are typically made from FR4, a material that is both non-biodegradable and difficult to recycle. Separating metals and recovering materials from FR4 based PCBs is energy intensive and often economically unviable, resulting in e-waste or incineration with significant energy consumption.

Printed electronics can use substrates that are easier to reclaim or biodegrade, such as paper or compostable plastics. However, one must ensure that these materials have the proper approvals in regard to usage and industry.  Since the materials are not laminated in multilayer constructions, disassembly and material recovery become far simpler.

Design for Sustainability Opportunities or Circular Design

Printed electronics open the door to circular design by potentially allowing the product owner to choose recyclable or biodegradable substrates, use non-toxic low impact materials as inks, and employ a design for a closed loop recycling and disassembly that supports cradle-to-cradle electronic life cycle management.

The product life cycle management in relation to end of life and consequently recycling, constitutes an area of particular interest and potential significant sustainability advancements. The printed electronic material composition allows for more sustainable recycling methods with a higher amount of recyclable materials, reduced energy consumption as there are fewer types of advanced materials to separate, and less toxic air emission.

Factual Cases Already Changing the Industry

Smart packaging companies are embedding printed sensors that monitor temperature, humidity, or tampering, using paper substrates that are fully recyclable, enabling intelligent packaging without increasing e-waste.

Wearable healthcare devices or "electronic spider silk" can be printed directly on human skin using skin compatible, flexible sensors made via additive printing on biodegradable materials, to offer real-time diagnostics without contributing to plastic pollution.

Solar energy firms are exploring printed photovoltaics on plastic or textile substrates, enabling lightweight, low-cost, and recyclable solar panels suitable for portable or emergency power.

Printed Electronics and Challenges to Overcome

The sustainability advantages of printed electronics are evident, however challenges still remain. Conductive inks, specifically silver can be expensive, and the total environmental impact depends on material sourcing. The mechanical durability, miniaturization, and the conductivity of printed electronics is also continuously evolving compared to traditional subtractive printed circuit boards.

Advances in materials science and economies of scale will inevitably result in printed electronics becoming increasingly mainstream. New developments in graphene, organic semiconductors, and recyclable conductive polymers are further tipping the scales in favor of sustainable solutions.

Regulatory shifts, consumer awareness, and investor pressure will only continue to drive the need for eco-friendly manufacturing, and printed electronics offer a way to meet those demands without compromising on functionality or performance.

Conclusion: Design for Sustainability

Printed electronics represents a disruptive technology and consequently a paradigm shift regarding how we can innovate and design electronics, manufacturing, and organize the electronic lifecycle. By embracing an additive, low impact environmental approach, engineers and product owners can design products with sustainability as a key ingredient.

A technical innovation such as printed electronics is a viable solution to support the growing global environmental challenges and stricter regulations. The facilitation of recyclability and the reduction of toxic waste, will further support the sustainability of the circular economy.

Explore how Altium Designer supports printed electronics.