An Introduction to Design-for-Environment

Environmental management systems in most businesses start out by focusing on reducing the environmental impacts of processes. However, processes themselves change over time: new products are introduced with new manufacturing methods, the product-service mix changes; new capital equipment is purchased, and so on. Design-for-Environment (DfE) techniques can be used to ensure that these changes reduce the environmental impacts of the organisation as well as providing a vehicle for the pursuit of technical and commercial goals.

From an Environment Manager's viewpoint, adoption of DfE in the company provides another avenue for the cost-effective pursuit of environmental performance improvement. Take the example of a paint maker seeking to reduce solvent (VOC) emissions. Emissions abatement in the factory is important for the local environment and reduces waste. However, there soon comes a point at which further abatement of process emissions takes out relatively small additional volumes of solvent. Reformulating products with 10% less solvent can - if it's technically possible - offer much greater overall reductions in solvent emissions, albeit those savings are in use rather than production.

Design-for-Environment Tools

This article introduces the range of tools that have been developed to assist the development and design of products and processes which are more environmentally benign.

The simplest tools in Design for Environment (DfE) are checklists: many companies use these when starting out on DfE initiatives, as they offer a simple way of ensuring that straightforward improvements are made. Most commonly checklists specify materials or substances to be avoided (negative checklists). Examples might be: eliminate CFCs; avoid mercury and cadmium; use no lead-containing pigments, and so on. These may be extended to include reduction or minimisation requirements, e.g. for VOCs. Checklists can be developed in a number of ways. One approach is to look at the requirements of customers and regulators in the countries where you sell, and to develop one or more checklists that reflects those market needs. Another approach is to rely on "standard" lists of environmentally-harmful substances such as the EC's "Black List". In some industry sectors, the checklists of industry leaders have been adopted by other companies (for example, in the automotive sector many have followed Volvo's lead).

Many of the tools available for environmentally beneficial product development or design have their origins in the process of life-cycle assessment (LCA). LCA is a technique for estimating and assessing all of the environmental impacts (positive and negative) associated with a product or process from the extraction and acquisition of raw materials, through product manufacture, distribution and use to ‘end-of-life management’ (disposal or recycling). Carrying out a complete LCA on a particular product system is a time-consuming exercise which requires a large amount of data and a certain amount of subjective judgement. It can also be very expensive. On the other hand, the data-gathering stage (known as Life-Cycle Inventory or LCI) often prompts many improvements on its own, without recourse to the more contentious impact assessment that follows. Detailed LCA and LCI studies have been carried out on a number of products for comparative purposes, and LCA is used to develop eco-labelling criteria (one of the reasons why these take so long to be decided). There have also been a number of studies on basic raw materials including common metals, many plastics, paper, woods and some building materials.

Neither comprehensive LCA nor compilation of an LCI are practical options for most firms when developing a new product or service and wanting to improve their environmental performance at the same time. A structured approach to design or development which considers the environmental impacts arising from each stage of a product’s life cycle is, however, possible for businesses of all sizes and within projects of all timescales.

Design-for-Environment Strategies

Designing for the Environment will in most cases involve one or more of the following strategies:

Product life extension - through :
  better reliability
  increased durability
  improved serviceability
  ‘multifunctionality’

Material life extension :
  making materials and components reusable or recyclable
  making separation of different materials quick and straightforward
  labelling components and materials to ease separation and collection
  keeping potential contaminants, e.g. adhesives, away from recyclable materials.

Reduced use of materials - making products lighter or smaller while performing the same function.

Switch from non-renewable to renewable resources, either in materials or in energy sources.

Energy efficiency - in use as well as in production.

Pollution minimisation - minimising pollution arising from all stages of the life cycle.

Matrix Methods

A simple, qualitative overview of the life cycle can help to identify which of these approaches is likely to yield benefits. 'Matrix' methods provide one such approach to assessing environmental impacts across the life cycle. In one simple version, Materials, Energy and ‘Toxicity’ (pollution issues) are identified for three stages of the life cycle: production, use and disposal. Some of the possible entries into a "MET" matrix for a jug-style electric kettle have been made below.

Common-sense consideration of the likely relative sizes of the different entries in this matrix is a good guide to opportunities for improvement. Calculation or measurements will provide a stronger basis for comparison of issues that are seen to be important or that present opportunities. In this case, the fact that kettles have relatively long useful lives leads to the conclusion that electricity consumption in use is responsible for most of the environmental impacts across the kettle's whole life cycle. Designing a kettle with better environmental performance should then start by trying to reduce the energy it consumes per mug of tea made. More energy efficient kettles have been developed, incorporating changes such as double-walled construction to reduce heat loss and even an indicator to show whether or not the water in the kettle remains hot enough to use for making hot drinks without being reboiled ¹.

At EuGeos, we use a slightly more sophisticated matrix approach to help analyse environmental impacts around the life cycle, with quantitative comparisons where they are available.

Eco-Indicators

Having decided on an approach to take in designing for reduced environmental impact, some form of indicator should be used to monitor progress. Examples of indicators that can be useful include: percentage recyclable content; energy consumption per year of typical use; weight of specified materials per product unit; etc.

A qualitative or even semi-quantitative approach to identifying opportunities may not be adequate in all circumstances to decide between design options - answering, for example, whether the environmental impact of a plastic waste-bin would be lower than that of the painted steel one. Sets of eco-indicators have therefore been developed and incorporated into some DfE tools which allow a numerical comparison of environmental impacts. These eco-indicators give some relative measure of the environmental impact associated with using a particular material, process or component, based on the results of LCA studies. Some large companies have developed their own eco-indicator sets for use in-house, reflecting the sources of raw materials used by the firm and its processes. There are also some general tools available which can be useful aids to designing products with lower environmental impacts. Care in their use is needed, however - they do not give absolute values for environmental impacts, rather useful comparisons valid for the conditions for which the source data was compiled. The range of substances and materials covered needs to be checked too, as it may not include everything your business uses.

Integration in the Design Process

As well as selecting the right DfE tool (or tools) for your circumstances and objectives, it's important to apply it (or them) at the right point in your product development process. Embarking on a quantitative LCA when all you have is an outline concept will be unworkable because of the design uncertainties, whereas leaving any consideration of environmental issues until later design reviews will restrict the scope you have to make changes. EuGeos can help you select or develop appropriate DfE techniques to suit your development process and to match the degree of freedom you have with respect to customer specifications and those other key product characteristics - price and technical performance.

¹Bielby, B. "Hot Water, Green Features". Eco-redesign Newsletter, Oct 1996, p.9

Contact EuGeos

 by email:
 by telephone: +44 (0)1625 434423