Demand management system developed to ensure maximum saving and energy usage improvement solutions part of a wider effort to save on costs.
One of the most repeated statements in South Africa and the rest of the world must be: “Our electricity bills are making us uncompetitive and stretching us to the limit.” This is of course if you can get the power in the first place as is the case in South Africa presently and has been a challenge for many businesses in South Africa for many years now.
However, energy costs are still one of the significant economic forces driving foundry operations today and the necessity to reduce energy costs and improve operating efficiency should be a priority at all foundries.
There are various studies that have been done to determine exactly how many kilowatt-hours are required to melt the metal needed to make a casting. But overall, and depending on the foundry, energy costs in a foundry can account for between 15% and 20% of the input costs and of these costs between 50% and 80% of the costs are in the melting process alone, depending on which study you read. Nevertheless, a 10% saving in energy efficiency is therefore a substantial amount that could rather be spent in improving efficiencies and production rates in other areas of the foundry, which could drive profits up.
“An intelligent demand management system is an important part of today’s process management and is not just for energy management. It allows you to have real-time monitoring for process analysis, whether it is from your PC/desktop or your cellphone, it allows you to have condition monitoring for predictive maintenance, energy monitoring for energy management, central data management and access to a dynamic electricity market.”
For induction melt shops, optimising melting cost-per-ton starts with minimising kW and kVA demand, and enhances the value of every ton poured. Optimising your melt system to reach the lowest possible kilowatts (kW) and kVA of demand as part of your overall energy management programme is critical to competitiveness in an industry where energy costs are a constant concern. The importance of melt-shop power supply utilisation, efficiency and performance, and how it impacts power demand should be examined carefully. It directly influences the connected kW or kVA of demand for a given production rate. By increasing your melt shop power utilisation rate you will increase and maximise the volume of metal poured per kW and kVA of demand. There are various ways that you can review these factors within your own foundry to find additional opportunities for conserving melt shop energy demand and usage.
There are many critical factors influencing production versus demand, including efficiency, melt system performance, power supply technology and power utilisation. The factors that are specifically part of power utilisation include equipment type and configuration, operating practices, melt preparation and the charging and pouring processes.
“All of these factors need constant attention but it still does not divert from the fact that a proper demand management system is an important part of today’s energy management. By systematically limiting power, peak loads are avoided, and electricity costs are reduced. Savings can be realised in almost every company and especially in melting operations because of the high energy usage,” explained Wessel Watt of the Watt Group.
“An intelligent demand management system is more than just a load control system. Not only would your energy consumption be efficiently optimised, your other performance and process data, which are necessary for your production and processes, would be collected and monitored too. Simultaneous and connected processes then become transparent and can be managed and changed individually. The control potential is dynamic and instructions are easily allocated. Through the advanced, live monitoring and detailed analysis you can generate additional profits and be equipped with the latest technology in your energy management department.”
“I sold one of the first energy demand systems to the foundry industry in South Africa to Atlantis Foundries more than 10 years ago and we have replaced this system with our latest Watt Demand system in January 2022.”
“We have been successful in supplying systems to both plants of Auto Industrial Group (Isando and Wadeville), to Agni Steels (The company has changed its name to Coega Steel), as well as Naledi Foundry. Last month – July 2022 – we installed a system at High Duty Castings.”
“At the end of 2018 we started to develop our new generation system which we named the Watt Demand System (WDS) and were ready to take it to market at the beginning of 2020 but unfortunately, Covid struck. The new system is internationally certified, and we are going to start marketing it to the US market from September 2022. Our partner, Soeren Schneider Services, is primarily responsible for the European markets.”
“Our system is also able to monitor and collect the data of all mediums used to enable ISO 50001 qualifications. We are also able to monitor performance of energy users against the manufacturers’ specifications and report on discrepancies.”
Examples of energy savings
“We cannot give you any examples in monetary terms because everybody has different charges and melt at different times, but the higher the demand levels and the more users that can be optimised, the higher the potential savings. We will give you some examples in terms of kVA and this will give you an idea of energy savings and you can work out the cost savings.”
“At foundry A previously the average kVA maximum was 6 634kVA with some readings as high as 8 284kVA. Since the active monitoring and control started the average high has moved down by 360kVA to 6 277kVA. This saving together with the prevention of previous high peaks in excess of 8 000kVA has made a significant difference on the monthly electricity bill. During the installation and test phase, the maximum demand level was fine-tuned to ensure maximum saving without effecting production output.”
“At foundry B previously the average kVA maximum was 4 240kVA, with some readings as high as 4 520kVA. Since the active monitoring and control started the average high has moved down by 370kVA to 3 870kVA. Again, a significant saving.”
“In one case the foundry is saving R1.4 million a year on energy costs without any effect on their production.”
“Our system not only allows you to optimise your energy consumption efficiently, it also allows you to collect other performance and process data, which are necessary to monitor your production processes.”
“By systematically limiting power, peak loads are avoided, and electricity costs are reduced. Savings can be realised in almost every company.”
“An intelligent demand management system is an important part of today’s process management and is not just for energy management. It allows you to have real-time monitoring for process analysis, whether it is from your PC/desktop or your cellphone, it allows you to have condition monitoring for predictive maintenance, energy monitoring for energy management, central data management and access to a dynamic electricity market.”
For further information contact Watt Industries on cellphone 083 652 2007 or TEL: 012 111 7677, email wessel@watt-group.com or visit www.watt-group.com
