Sustainable design represents the consideration and application of sustainability fundamentals within the process of engineering and design. Whilst this article concentrates on products and similar manufactured components, the elements of sustainable design can be applied across any and all types of projects, builds and constructions.
Design engineers cannot be expected to have complete command over the many aspects of a project that may affect its inherent sustainability, but what they can influence has significant implications for a products’ environmental impact. Typically we see cost, time and quality constraints dictated by the customer and this can limit the extent to which a designer can integrate best-practice sustainability principles into their design. Furthermore, where components are being made, how they are shipped or the materials suppliers are using are not decisions design engineers typically have a say in. Given this, sustainable design presents a great challenge to today’s designers, but one worth taking on – for the good of the Earth.
The following quote from Dr. Leyla Acaroglu brilliantly encapsulates the foremost ideals of sustainable design practice:
“When sustainability is applied to design, it enlightens us to the impacts that the product will have across its full life cycle, enabling the creator to ensure that all efforts have been made to produce a product that fits within the system it will exist within a sustainable way, that it offers a higher value than what was lost in its making, and that it does not intentionally break or be designed to be discarded when it is no longer useful.”Dr. Leyla Acaroglu
It could be said that the only true sustainable or ‘green’ product is the one that’s never made. In this sense, we can only ever hope to make products more sustainable or more ‘green’. The most sustainable solution is to avoid making unnecessary items altogether.
Sustainable design cannot be verified by any one benchmark or indicator. Many might assume that carbon emissions are the major measure of a product’s lifetime sustainability, however sustainable design needs to take into account a lot more than its contribution to climate change.
Impact metrics, or the elements of sustainability on which certain products can be compared, will vary between goods and the intended use of these. The appropriate technique for evaluating the environmental impact of a design depends on the answers to the following three questions:
- What impacts do you care about? Does toxicity matter? Water use? Only CO2 equivalents?
- What is the scope of the assessment? How far up and down the supply chain does it go? How much of the product’s lifecycle should it reflect? What is the unit of analysis for the assessment? Is it for a component, an assembly, a product, a system?
- What types of metrics are appropriate for your purposes? What will the assessment information be used for, and by whom? Is rigorous detail necessary, or is a “rough idea” good enough?
Extracting understanding of product sustainability metrics by being attentive to the aforementioned impact questions gives the designer a clear cut view of what elements of their design will need improvement, adapting or removing. There are of course, always the lingering barriers of time, cost and quality but responsible designers will ensure customers are made aware of the factors that are undermining the sustainability of their projects. In a changing world, customers are consistently becoming more and more aware of long term benefits derived from sustainable practices which can include greater demand for products, longer life cycles or wider incentives.
Today, creating a sustainable, regenerative, and circular economy takes a significant shift in systems thinking – from consumers and manufacturers to governments and communities. Sustainable design dictates that the things we make to satisfy our needs must follow a circular lifecycle flow, as opposed to the traditionally linear flow of products from material, to manufacture to use, then waste. The concept of the circular economy is not a new one, but recently, there is more and more consideration being given to the principles of the circular economy as creative designers, products and businesses emerge with a common goal of closing-the-loop in the lifecycle of goods. The circular economy essentially embraces and combines a number of pre-existing theories and approaches to sustainable design, and it prescribes the need for ‘end-of-life’ considerations to be regarded at the start. Some of the concepts that ‘circularity’ embraces are described below.
Design for Disassembly
A design approach that enables the easy recovery of parts, components, and materials from products at the end of their life. Recycling and reuse are noble intentions, but if a product cannot be disassembled cleanly and effectively they are impossible, or at least cost prohibitive to achieve.
Design for the Environment
Reduce the overall human health and environmental impact of a product, process or service, where impacts are considered across its life cycle. Different software tools have been developed to assist designers in finding optimised products or processes/services.
Product Stewardship, sometimes known as extended product responsibility (EPR) means whoever designs, produces, sells, or uses a product takes responsibility for minimising the product’s environmental impact throughout all stages of the products’ life cycle, including end of life management. The greatest responsibility lies with whoever has the most ability to affect the full life cycle environmental impacts of the product. This is most often the producer of the product, though all within the product chain of commerce have roles.
Cradle to Cradle
William McDonough and Michael Braungart popularised the notion that product lifecycles should be considered not as cradle to grave, but as cradle to cradle. The key idea here is that there is no such thing as a “grave” at the end of use, since everything goes somewhere. As they say, there is no such thing as “away.” Given that, in order to be sustainable all of the elements of a product that has reached the end of its useful life should be designed to go somewhere where it can serve as the input to another system.
In practical terms, Cradle to Cradle requires products to be designed in such a way to ensure that all materials can be classified into one of two cyclical systems:=
- Biological cycle: Materials that naturally biodegrade and can be returned to the ecological system. Examples of such materials are natural fibres and bio plastics.
- Technology cycle: Metals, oil-based plastics and chemicals are examples of valuable materials that can be recycled or reused producing the same or better quality in closed systems, provided they are not mixed