You may be familiar with the concept of Design for Manufacturing or Design for Manufacturability. I suspect that many 3D InCites readers have given less thought to Design for Sustainability (DfS).
Why does DfS matter?
It is essential to design with sustainability in mind because choices in materials, processes, and product specifications define much of the environmental impact of a product. The primary goals of DfS are to reduce the depletion of natural resources and energy consumption.
A proposed Ecodesign framework from the European Commission aims to “reduce the negative life cycle environmental impacts of products and improve the functioning of the internal market.”
Sustainable design practices cover a wide range of issues. Here are some questions that can apply whether you are designing an electronic device, a microprocessor, or a piece of fab or assembly equipment.
- How much energy will be required to make the product, and how much will it consume during use? Can your design choices reduce either of those?
- How can you make the product with fewer virgin raw materials (in variety and quantity) without compromising performance?
- Which materials or chemicals in your production process are toxic, and can you replace them with safer alternatives?
- How can you design out inefficiency and waste by creating less scrap or building reuse into a process?
- Where can you leverage standards to improve interoperability with products from other manufacturers?
- How long is the product expected to last, and where are the weak links (parts or components most likely to fail first)?
- What can you change to make the product more durable and repairable when something goes wrong?
A recent post in the Sustainability 101 series discussing the Right to Repair addressed the final three items on this list. Earlier posts have covered toxic chemicals and energy efficiency. This post examines energy consumption, materials sourcing, and reuse.
One way to consume less energy during manufacturing is to run processes at lower temperatures. It isn’t as simple as changing equipment settings because temperature specifications and materials selection are directly connected. Trade-offs can be complicated, and any changes should not sacrifice performance or yield.
Beyond affecting processing time and temperature, choices in materials affect the embodied energy in a product. For example, it takes over 20 times more energy to produce a ton of virgin aluminum than a ton of recycled aluminum. Silicon is one of the most energy-intensive materials, dwarfed only by gold.
How can you reduce the weight of virgin metals and semiconductors in your products? One approach, especially for steel and aluminum, is to source recycled metals. That makes a greater difference if you build cars or heavy machinery, but every bit helps.
Sustainable materials selection during design goes beyond choosing recycled versus virgin metals. It is helpful to rethink any material or component that comes from fossil fuels. In some cases, biobased alternatives may work as well as what you normally specify. Henkel, for example, has introduced several biobased adhesives for various applications.
The most common stories about reuse and recycling seem to be about water. Finding ways to filter and reuse water or solvents within a facility is always a good idea. There are also many other ways to incorporate reuse into your design.
The Smart Cut™ process from Soitec is one example of building reuse into a process. The process transfers a thin layer from one wafer to another. After the layer is transferred, the donor substrate is reused. That approach reduces silicon consumption.
The company’s latest product applies the same concept to silicon carbide substrates for use in electric vehicles. Soitec claims to reduce greenhouse gas emissions by 75% compared to conventional SiC processing using solid single-crystal SiC substrates.
By looking holistically at everything that goes into designing a product, it is possible to develop creative thinking that incorporates DfS. What is your company doing in this area? Comment and share your success stories