14 DAY TRIAL // Conventional wisdom has it that remanufacturing an item from leftovers is cheaper and less energy-intensive than producing the same object from scratch. Researchers in the United States show in a new study that, while this is mostly true, there are some exceptions to the rule.
The team, based at the Massachusetts Institute of Technology (MIT), in Cambridge, explains that there are some items which take up less energy and work if they are produced anew, rather than from debris.
Notable examples of products created through remanufacturing include vehicle tired, inkjet cartridges and even entire engine blocks. But the MIT team looked at a wider array of objects, which were divided into several classes.
A total of 25 case studies were carried out, on products split between 8 categories. MIT professor of mechanical engineering Timothy Gutowski was the leader of the team that conducted the work.
Cases where remanufacturing actually cost more energy than creating an object anew were found to exist half the time. In other words, half of the objects we use may be produced anew, at lower energy and labor costs than if they were remanufactured.
Interestingly, for the vast majority of the objects analyzed, the amount of money and energy that was saved by remanufacturing was undetectable or negligible. The reason why the MIT results are so different from expectations is because experts carried out a life-cycle analysis.
This means that they took into account the total amount of energy used over the lifetime of a given product. Other works simply calculated the energy used to produce the object on the assembly line.
Another important factor to consider is the fact that remanufactured products generally tend to be less energy efficient than their new counterparts. As such, they use extra energy over the course of their lifetime, therefore canceling out the initial energy-saving benefits.
This investigation “takes what appears to be a simple, straightforward problem and shows that the world is a far more complicated place than people thought,” Gutowski explains. Details of the work were published in the latest issue of the journal Environmental Science & Technology.
Oftentimes, “new technology shows up that is so much more efficient, from an energy point of view, that you should get rid of the old device,” the team leader goes on to say.