The first rule when dealing with the removal of waste from a production plant writes itself: don’t have any waste! The second rule is always to remember that the first rule is not possible – and then plan from there. The first rule is beyond Utopia – but it provokes a response: to settle for nothing less than the ‘least waste’ environment that can be created.
What sort of payback might organisations reap from getting the ‘War on Waste’ equation right? Research from the Institute for Manufacturing (IfM) – part of the Department of Engineering of the University of Cambridge – calculates that, if every factory moved towards optimum sustainable performance, there could be a 24% profit gain, 30% more jobs generated and 9% less greenhouse gases shared across that sector.
The IfM’s Zero Loss Yield Analysis (ZLYA) tool has been designed to help manufacturers identify hidden losses by using existing data streams and putting waste value into the context of the business as a whole. The results from this approach are often very illuminating, it says. “One manufacturer we worked with to reduce plastic waste discovered that its actual waste was way greater than they had thought. Using this approach uncovered underlying problems within the factory, including the imbalance in the production system.”
The factory, which produces plastic products by using injection moulding, believed it was only rejecting 1% of its main product (plastic coffee capsules comprised of a cup and a lid). Based on their ‘reject rate’, the manufacturer thought it had a 99% yield. But, when looking at what was actually happening, the waste was 14 times that amount. “They also discovered there was a major imbalance in product production,” adds the IfM. “They produced 14 million capsules and 16 million lids – so a two million item surplus waste of materials.”
SHADOWS OF WASTE
During the past 20 years, it is such anomalies that have spurred Professor Steve Evans and his team of action researchers to chase down the ‘shadows’ of wasteful inefficiencies cast by the manufacturers of anything from cement to cars to clothing. “There are examples of inefficiency and waste all around us. But it’s either ‘part of the furniture’ of operations or you can’t see it – it’s the water used or the energy consumed,” says the director of research at the Centre for Industrial Sustainability, part of the IfM. “Factories are responsible for about 36% of greenhouse gas emissions globally and often the carbon footprint of manufacturing operations is closely related to how efficiently they operate. It’s crucial for profit margins that resource efficiency is the best it can be and it’s crucial for the planet that industries reduce their carbon footprint.”
Evans points to Toyota as being a leading and globally recognised light in industrial sustainability. “The Toyota factory in Burnaston, near Derby, has been reducing the energy it uses to manufacture a car by at least 8% every year for 14 years, resulting in [more than a] 70% reduction over the period,” he reports. “It can now make four cars for the energy it used to take to manufacture one car.”
The company started a programme called ‘no production equals no energy’. That means, when the factory is shut down in the middle of the night, they shouldn’t be using any energy at all. “Crucially, they’ve managed to do all of these improvements by identifying efficiencies in energy usage, not by depending on a major new technology to revolutionise the business,” adds Evans.
His team has now had what amounts to thousands of interactions with industries – including Toyota, Airbus UK, Jaguar/Land Rover and Dyson – either directly or indirectly through use of their open-source tools. As a result, he and colleagues can spot patterns in the inefficiencies that hold industries back from performing better. “None of us wants to solve one problem at a time,” he states, “so we’re always looking for patterns across multiple industries, pinpointing places where resources are wasted and where opportunities are missed for creating value.
“Quite often, we don’t need to collect much more data or even any at all, but we do help them to present the data they’ve already collected in their own factory in different ways,” says Evans. “And, all of a sudden, it goes from being just numbers in the spreadsheet to them saying: ‘I can now see the waste!’ All we’re doing is asking the right questions and presenting the results in a way that makes the invisible visible.”
ALL IN THE DATA
Dr Dan Summerbell is an equally vocal advocate for using existing data to find waste. “We’ve been working on one way of analysing waste that tries to put this into the context of the process as a whole,” the IfM doctoral researcher comments: “And, in a fundamental sense, this compares the two most important metrics that a factory manager has: how much raw material they are buying; how much they are having to pay for; and how much they’re being paid for in the form of useful product.”
It’s a simple idea in principle, he concedes, but the key challenge is: how do you get the data? “Just as with any waste analysis programme, it’s not always easy to put the numbers behind it. We’ve tried to develop a technique that uses existing factory data – things such as invoices, bills of materials – rather than having to put in place an expensive monitoring system or do lots of line studies that only give you a snapshot picture,” says Summerbell. “And the key outcome of this technique is that it puts every source of waste into the context of the whole production system by comparing the real world to the ideal world where you only buy just enough material to make the useful product that’s going out to your customers.”
The technique has been applied within a range of factories, including the plastic coffee capsules manufacturer referenced near the start of this article. Another company that the IfM has engaged with makes steel parts. “You do expect a certain amount of waste, in this case, because you can only have your parts so close together in a steel sheet before punching them out would cause damage,” explains Summerbell. “Ideally, you should get about an 80% yield and this factory’s estimated return was exactly that. However, looking at it in a zero loss context, the yield was only 34%. A large amount of that was going into inventory, so they were building up stocks of raw material that weren’t necessarily going to be used in the long term, because they have a very fast turnover of the parts they make.
“Also, even though they were making 1,000 different SKUs [Stock Keeping Units], a third of their losses were associated with only five products.” Concentrating on those products,
he adds, would have delivered a good return on investment, given the factory a focus on their rework and improved the nesting processes that were driving those losses.