Sustainability is the ability to remain in a predefined state of things indefinitely. In a broad sense, sustainable actions seek to adopt methods that do not lead to depletion of, or strain on resources in the pursuit of satisfying present needs to a level that threatens the well-being of future users of the same resource. Sustainable design can thus be defined as a design philosophy that seeks to comply with the principles of social, economic, and ecological sustainability.
Sustainable design can therefore be conveniently discussed under the following categories.
Socially Sustainable Design
Socially sustainable product design includes all product ‐based solutions that enable positive change in the present and future of society without sacrificing environmental or economic sustainability. This design philosophy seeks to address the multifaceted social issues of; inclusion, equity, ethics, justice etc. It calls for social responsibility in the design of products in all its phases of development. In design stage, user participation in establishing real needs of the user is largely emphasized and has given birth to a design approach called “participatory design”.
Considerations of how the product features will influence the manufacturing process and the type and quality of employment the manufacturing process will create are made in product design. Questions like; “How do the product features affect the safety of the factory workers?” and “How do human capital relate with the machinery used in production?” give rise to another design approach – Ethical design approach.
Social sustainability requires designers to as well pay attention on how their resultant product satisfies the needs of various groups of people indiscriminately, whether physically disabled or not. For example, many building codes and regulation require all major commercial and social buildings to have provision of easy access by physically disabled persons, notably wheelchair users. Such considerations have given birth to the democratic design approach.
Economically Sustainable Design
Economic sustainability calls for efficient use of resources and reaping optimally from every factor of production. This design philosophy focuses on ensuring designs come up with products that exert least economic pressure on resources both in production stage and during their useful life. Factors like obsolescence of products and their resale value are central to this design philosophy. Economic sustainability has given rise to different design approaches, among them “futuristic design approach” and “Minimalism”.
Futuristic approach aims to come up with products whose usability extends to the future. Futuristic design essentially tries to meet both the present and future product functional demands. Futurism therefore contributes to economic sustainability of products by ensuring they remain relevant to their intended use over a long time hence less disposal rates and costly replacements. Machines are a perfect example.
Minimalism is central to the three pillars of sustainability. From Ecological conservation to social responsiveness and economic efficiency, minimalism gives infinite solutions. Minimalism abstracts products to their most fundamental forms by removing clutter and unnecessary complexities. It stresses on the need to use few materials and reduce everything to its simplest form. Use of less materials means less time on production, less manpower, simple equipment and less energy needed to assemble a product and finish it.
Environmentally Sustainable Design
Herman Daly, an ecological researcher defined Environmental sustainability from a “natural capital conservation” point of view. He broke the problem into three components. For every product designed, it is environmentally sustainable if:
1. For renewable resources the rate of extraction does not exceed the rate of regeneration (sustainable yield);
2. [For pollution] the rates of waste generation from the product manufacture, use and disposal do not exceed the assimilative capacity of the environment (sustainable waste disposal); and
3. For nonrenewable resources the depletion of the nonrenewable resources required for the product is accompanied by proportionate development of renewable substitutes for those resources.
Environmentally sustainable design is therefore a design philosophy that seeks to conform to the above basic principles throughout the whole product life-cycle.
In order to achieve environmental sustainability in design, the following strategies need to be adopted.
Whole Systems And Life-Cycle Thinking
All products bear environmental impacts throughout their lifecycles and every product is a part of social, ecological and technical systems that can be wholly appreciated through whole systems thinking. Opportunities for efficient use of resources like materials and energy can be discovered in the conceptual design stage of a product by identifying the most relevant problem to solve.
Through Lifecycle thinking you can quantify environmental impacts and be able to prioritize, set metrics around, and reduce them.
Green Materials Selection
This involves selecting materials that least impacts the environment negatively. These are materials that are abundant, have low embodied energy, non-toxic and meet or exceed regulations. This strategy has given birth to what is called eco-design.
Improving Product Life Time
Sustainability in design demands optimal utilization of materials and energy in a product lifecycle. Ideally a sustainably designed product has a closed-loop lifecycle. This implies the product produces zero waste at the end of its life that can’t be utilized by industrial processes like recycling or natural processes like decomposition
In determining a product’s longevity, intended use is considered. Products intended for short lifespans e.g. packaging materials should be designed to be recyclable or easily biodegradable. Other products like a stainless steel spoon are designed to last a lifetime.