Manufacturers are lining up at UNSW’s Life Cycle Engineering research group, in order to save money and improve their environmental footprint, according to Associate Professor Sami Kara, founder and head of the group, which is based in the School of Mechanical and Manufacturing Engineering.
Sami says most existing factories in Australia are highly inefficient in their use of water and energy. “More and more companies are coming to us saying ‘We want to cut down our energy use’. As well as saving them money, this can easily translate to reduced environmental impact, so unlike many environmental solutions, it’s a win-win situation for manufacturers – cost and environmental footprint reduction at the same time.”
Sami says work at large manufacturers has shown that there is usually very little understanding of electricity and water usage. “The electricity gauge at the factory door is often their understanding of electricity consumption,” he says. “Once we understand the flow, we can look at technological solutions.”
For example, at one factory, Sami’s team discovered that auxiliaries, such as airconditioning and heating, had a greater impact on power consumption than the production line itself. Like many Australian factories, the building was designed in the 1960s, without much regard for the conditions or the manufacturing process. A great amount of heat generated by large ovens was getting caught under the ceiling, and air-conditioning was then used to cool the building. “We’ve proven that the heat loss is more than enough to generate power,” Sami says. The group has proposed installing a generator that will produce power for the factory and export power to the grid at times, using this “waste” heat and heat from the steam boiler. “Their power bill is in the millions, and so if you have a $250,000 investment, it will pay off in less than a year’s time,” Sami says.
The group is also working on intelligent monitoring systems that can assess changing energy use in a factory and modify auxiliary systems as necessary. For example, the same manufacturer has clean-room facilities that need heating, ventilation and stabilisation of particles, but the facilities aren’t used on the weekends. “The question we are asking is can we turn the systems off on a Friday afternoon, and if we do, how early should we turn it on again before the people start working again on Monday morning? It would require a huge kick of energy to clean up the air, so would it be better to run it all weekend at a low rate, or run it shorter and more intensely? We will develop some sort of monitoring and control system which gives you the best possible energy consumption.”