As the use of household and industrial power increases, power consumption inevitably rises and places the already overstretched electricity grid under renewed pressure. While Eskom battles to bring new power stations online, the energy utility regularly issues appeals to heavy users to reduce consumption.
“As a substantial user of electricity and coal, Bidvest Laundry Group is very conscious of our duty to reduce our power consumption in order to help safeguard the national power grid,” says Hans Hunink, Managing Director of Bidvest Laundry Group. “We’ve taken a strategic approach that aims to reduce our power consumption in the course of everyday business, rather than implement emergency, temporary measures during the cold weather.”
The Bidvest Laundry Group launders an astonishing 138.7 million items of clothing, linen and walk-on mats a year. To achieve this, the group goes through equally large amounts of water and energy. Some 1.6 million kilolitres of water are used annually. This is enough to fill more than 40,000 swimming pools.
Heating all that water up to the optimal temperature for ensuring a clean wash, together with the heating of driers and ironers - the finishing equipment - also consumes huge amounts of energy: 8 million kilowatt hours and 15,000 tons of coal in 2012. In fact, the laundry group accounted for 6% of the Bidvest Group’s total carbon emissions.
Consumption at this level almost inevitably means that big savings are possible—with the application of some lateral thinking and the latest technology, of course. As a result, Hunink and his team have been able to reduce the company’s carbon footprint substantially, and save water and energy into the bargain.
So, how are they doing it? The key lies in understanding one basic fact: commercial launderers require a supply of hot water (80°C or more) and hot ironers and dryers (70C-160C.) In the case of Bidvest Laundry Group, coal-fired boilers are used to create steam that provides the solution to this requirement at a constant pressure of 9 – 10 bar.
The first line of attack was the wasteful process of simply discarding dirty (but still hot) water down the drain. Bidvest invested in high-tech aquatherm or heat-exchange systems to transfer this heat to the incoming cold water. On average, water entering the wash process is now 50°C instead of 20°C, meaning the boiler has much less work to do. Reduced coal consumption is the result, whereas previously a boiler took a ton of coal to produce seven tons of steam, one ton of coal now produces 8.2 tons of steam.
In addition, the reduced differential in the temperature of the incoming water and the heated water means that the boilers are able to maintain a more constant pressure. This means that finishing equipment such as steam presses, dryers and ironers operate better, providing a better result for customers.
Another innovation has been the installation of variable speed drive (VSD) technology to help improve the performance of the laundry equipment. Before this technology was installed, motors ran at a standard speed. VSD technology means that the motors can be run at the speed demanded by the task in hand. Sometimes, this can result in a reduction in the revolutions per minute of up to 50%.
“Only using as much electricity as is needed to do the job translates into significant power savings,” Hunink explains.
Other initiatives are underway to reduce water consumption in the laundries, and the consumption of petrol by Bidvest Laundry Group’s fleet of 115 trucks.
“Bidvest as a group is committed to being a good corporate citizen, and we hope our energy-saving investments will play a role in protecting the electricity supply this winter,” concludes Hunink.