In a recent workshop hosted by General Motors SA at their Kempston Road plant, 31 delegates representing 23 suppliers who manufacture parts and components for GM’s assembly plants in Port Elizabeth, learnt how to reduce production and energy costs.
The workshop came after GM Utilities engineers conducted energy audits at some suppliers in an effort to identify opportunities to reduce consumption.
“We are working together with our suppliers as partners not only to reduce production costs but to also ensure that our suppliers have the most efficient and sustainable operations possible in terms of energy consumption,” says Craig Beetham, GMSA Energy and Utilities Co-ordinator.
Within manufacturing it’s the processes that consume the highest amount of energy. For example at the GM Struandale plant the majority of consumption can be attributed to the paintshop which is responsible for 85% of energy consumption at the Struandale plant. “Energy saving in the industrial processes is often under estimated and overlooked for general facilities such as lighting and air conditioning which are easily identifiable energy consumers.”
GM’s energy audits revealed that while some suppliers had good energy saving practises in place there was room for improvement particularly when it comes to energy consumed in the industrial processes which often have the highest percentage of consumption in the industrial environment.
According to GM engineers, businesses can make significant reduction in energy consumption through close scrutiny and analysis of high consumption processes caused by oversized equipment, processes that involve heating, fans and pumps, compressed air and after hours consumption.
Beetham refers to a process which heats up water to illustrate how an inefficient and poorly designed process can cost a company money through unnecessary consumption. In a poorly designed process there might be small amounts of steam or vapour escaping from the machines or pumps.
This according to Beetham can be expensive “a process losing one litre of water per minute through evaporation would require an additional 37 kW of energy to compensate for the loss which can add up to R200 000 per annum if ignored” says Beetham.
He adds, “we have found that there is often more value in time spent evaluating processes and looking to reduce energy consumption there rather than only focusing on general utilities.
We challenge all our suppliers to look at every part of their industrial processes, and reassess their set-points for temperatures and pressure because this is where there’s often wasted energy in the system.” In addition to the cost saving benefits, there are often zero or minimal implementation costs involved with paybacks of less than 12 months when implementing the changes
