As contemporary products such as smart phones, machine tools, and even sports shirts become increasingly complex, so too does the difficulty of manufacturing these products in a sustainable and resource efficient way. Complex production demands novel materials, new manufacturing processes, and dramatic shifts in assembly and distribution methods. In a world driving towards reducing resource consumption, tracking the environmental impact of these products is important, but very challenging.
In recent years “closed loop” systems in manufacturing have become increasingly prevalent. As illustrated below (Figure 1), where these systems are successfully implemented, products are not just recycled. Each of their components are recovered at the end of their first useful life, reducing the need for use of primary resources such as minerals, metals and fuels and consequently minimising the environmental footprint of production. Here, we discuss how the drive towards closed loop and more efficient manufacturing processes is taking shape, and consider the importance of collaborative working as a catalyst for realising these efficiency savings.
How can the efficiency of existing manufacturing and design processes be improved?
Figure 2 shows how raw materials or components are converted into products using resources such as people’s efforts and utilities. Many processes are used, by-products produced, and emissions made to air, water and land. To achieve maximal recovery and reuse of materials, manufacturers need to understand much more about each step of their processes and supply chains. In practice this requires a reduction in complexity, consumption and cost, for example:
Continuous Improvement – the classic approach is to continuously improve every step in the existing process to improve quality, speed, yield or margin. These incremental improvements bring benefits in factors such as logistics or material use, which has a knock on benefit to overall environmental footprint.
Debottlenecking – existing processes can be simplified by replacing one or more steps with more efficient equipment or processes. Examples include using the latest technologies such as rapid computer numerical control (CNC) machining centres and replacing human labour with robotics.
Another approach is to redesign existing processes by eliminating some of the manufacturing steps altogether. For example converting chemical production from batch to continuous production, which means that products can be made according to the needs of a specific customer and the need to produce large numbers of identical stock components is eliminated, thereby minimising wastage.
Sustainable feedstocks – using renewable or biologically sourced feedstocks rather than fossil based feedstocks is obviously more sustainable. In some cases, locally arising waste material can be used as a fuel or feedstock in a single factory, or co-located industries may collaborate to improve their respective efficiency by using waste heat from one process to supply heating to local communities.
A particularly promising example of a useful product made from food waste and biomass is the plastic, polylactic acid (PLA). The majority of the 4 million tonnes of plastic manufactured in the UK each year are made from fossil hydrocarbons, and a recent estimate by the Waste Resources Action Programme (WRAP) suggests that as little as 12.5% of this is recovered for reuse as recycled polymer. PLA is a closed loop product with the potential to change this, and crucially, PLA can be manufactured using the same processing routes as fossil hydrocarbon based plastic, so existing technology can service its manufacture.
Figure 3 summarises the steps to produce, use and recover polymers by splitting the end to end lifecycle process into five main sections. Even in this simplified form the process is complex, and any decisions as to which of the various recovery, recycling and disposal routes are available will be influenced by economics.
If 50% of the polymer present in PLA can be recovered and depolymerised to useable monomer at the end of its useful life, production materials could be reduced by a third. If production of PLA is widely implemented reduced carbon emissions, biomass production, fossil feedstock consumption and air, land and water emissions could be realised.
Radical process change – the adoption of novel, disruptive technologies can radically change the way a product is made or an effect is delivered. For example printable electronics removes the requirement to assemble and solder different electronic components onto a circuit board.
Another example is the full implementation of 3D printing, also known as additive manufacturing, where individual parts or products can be created locally from downloaded electronic templates, enabling domestic-scale production of, for instance, the injection of molten plastics. This technology affords the manufacturer control over scales of production, making it is as cheap per unit to produce single items as it is to produce thousands, and minimising waste.
Even more radical is introducing an entirely new solution to address an existing problem, such as the use of light instead of medicines to treat disease, which is known as healthcare photonics. This has recently been achieved by UK SME and CPI partner PolyPhotonix, using printed lights to treat diabetic retinopathy, the leading cause of new cases of blindness in adults, in place of injected drugs or laser intervention.
New business models – overall improvement can be achieved by examining the way in which products or services are delivered to customers and changing the existing business model. There are increasing moves to “servicise” some products by selling the service that the product provides rather than an actual product.
Examples of this include the “power by the hour” model employed by companies such as Rolls-Royce, where an airline pays to use an engine rather than to own it, or the sale by some companies of light rather than light bulbs and lampposts. Paying a supplier to provide light rather than the capital equipment in this way incentivises the supplier to invest in high quality, reusable, energy efficient products that do not require frequent replacement or maintenance.
Identifying changes such as these can reduce costs, and facilitate easier recycling and remanufacturing of items at the end of a product’s first life.
Public funding as a catalyst for improving efficiency
Some of the changes required in the manufacturing systems that make and deliver products to market are complex and extend across many steps in the supply chain. These changes are so significant that they may be beyond the implementation capabilities of individual companies, and to realise the potential resource efficiency benefits, require focused collaboration across supply chains over a number of years.
Public sector involvement is sometimes necessary to enable this collaboration and the UK government agency Innovate UK, steered by the Department of Business, Innovation and Skills (BIS), provides strategic input and funding to enable innovation to happen.
Targeted public investment can catalyse change by allowing early adopters to manage the business and financial risk associated with developing new manufacturing technologies. CPI has extensive experience of assisting SMEs and large organisations with applications for grant funding and the carrying out of CR&D projects to test and demonstrate new processes and technologies.
How should we design and manufacture future products to achieve resource efficiency?
Improved resource efficiency requires a different overall approach to future design and manufacturing systems, which should adopt the following three overarching strategies:
- Reduced process steps – reducing the number of machining steps also reduces associated waste, for example the use of technology such as 3D printing, which produces the right shape immediately without the need for further drilling and milling.
- Design reusability into the product – designing products which can be disassembled, tested and reused at the end of their first useable life ensures individual components are not wasted. An example of this is Caterpillar’s remanufacturing business, which takes back, rebuilds and re-warrants power plants.
- Implement highly resource efficient, flexible manufacturing processes – when successfully achieved these processes have high yields, producing only the required amount of material, potentially reducing emissions, capital, operating costs, raw material consumption, redundant stock and logistics costs.
Ultimately, collaborative, interdisciplinary working of the kind offered by partnering with CPI provides the greatest opportunity for commercial organisations to identify how these strategies can be implemented across the supply chain. Once properly understood and adopted, these changes can bring about a host of economic and environmental advantages, not just for the benefit of individual companies, but for consumers and wider society too.