Converting the Power of a March into Electricity

Scientists at the University of Leeds in the United Kingdom recently devised a new method of harnessing the power of soldiers' marches. They created a system that allowed for the capture of the large amounts of kinetic energy that was generated when columns of servicemen walked from one point to another. The innovation could essentially help reduce the weight of the average backpack by more than ten pounds (five kilograms), which would ease up the burden of having to walk tens of miles carrying large loads. The research took one million GBP ($1.64 million) to conduct.

The newly constructed devices created at the University make use of high-tech ceramics and crystals, which are used as piezoelectric transducers. Their charge is modified every time a soldier flexes their knees or ankles, and the differences in potential are then transformed into electrical energy. Piezoelectric materials are, by their nature, acted upon through mechanical stress, which modifies their internal structures, and creates disturbances in their electrical field.

The British instruments can also act as shock-absorbers, when they are placed on the soles of boots. They also cushion the impact that long marches have on joints, and reduce the stress on the legs when they are constantly bent over tens of miles. “As well as the obvious green issue of using so many batteries, it could also reduce a soldier's pack weight by around 15 per cent. And this technology could potentially have lots of applications in [civilian] street too,” the Director of the University of Leeds Institute for Materials Research, Professor Andrew Bell, adds. He has been the leader of the new study.

The expert explains that the need for the new system appeared when his team looked at the amount of weight soldiers carried around on battlefields such as those in Iraq and Afghanistan. On average, for a six-hour patrol, a regular infantryman takes with him a 75-kilogram backpack, filled with water, ammunition, batteries (about ten kilograms), and electronic equipment. If the new instruments are added to his clothes and boots, then the average weight on the backpack could be reduced by ten kilograms.

“By using the latest materials and electronics combined with taking into account personal differences in walking style we are confident we can make this work without adding to the burden or fatigue of the soldier wearing the device,” the expert concludes.