As featured in Castings SA – August 2021
There are varying opinions of the significance of cost of energy as one of the major challenges facing the foundry industry. In the midst of numerous production and sales challenges, does it really benefit a plant to spend time and money on energy management?
Evidence from the National Cleaner Production Centre (NCPC-SA) seems to suggest it is not only worthwhile, but it is a business imperative, particularly in light of the energy insecurity we face in South Africa. The NCPC-SA has developed numerous case studies to demonstrate how an assessment followed by implementation of energy management or optimisation of energy intensive systems, can shave millions off the cost of production across multiple industrial sectors.
One such case study was completed at Atlantis Foundry in the Western Cape, following seven years of energy – and water – efficiency interventions.
In 2012, Atlantis Foundry approached the Automotive Industry Development Centre (AIDC) to assist them with identifying saving potential in their operations. The AIDC had recently formalised an agreement with the NCPC-SA, with the objective of implementing resource efficiency and lean manufacturing interventions in the automotive sector. Following an assessment by the NCPC-SA, a number of potential energy and water efficiency improvements were identified.
Thembi Kodisang-Sibanda was the NCPC-SA project manager responsible for the project. “Because Atlantis was a manufacturer of blocks for automotive internal combustion engines, they were also part of the automotive sector. And it was our relationship with the AIDC that created the link.”
It was a proactive move by Atlantis which has proven well worth it – and began a journey that would result in an average of 37 000 MWh per year electricity savings.
According to Kodisang-Sibanda and her colleagues at the NCPC-SA, the potential for energy saving varies from plant to plant, depending on a number of factors. But it is almost always there, even where energy improvements have already been made – the notion of continuous improvement is the basis for the international energy management standard, ISO 50001.
“No matter what technology is used, melting of metals is energy intensive. Atlantis Foundries uses induction furnaces for melting its ferrous feedstock, therefore of the various challenges they are faced with, the cost of electricity is a prime one,” she says.
Based on the opportunities identified in the assessment, as well as further improvement identified as the energy management projects unfolded, Atlantis team, with involvement of Plant Engineer André Arendse, implemented a total of nine energy improvement projects between October 2013 and December 2019. A trial was run on an additional project, but this was discontinued because it prevented an increase in production.
A control system to limit maximum electrical demand was installed and power factor correction equipment was upgraded by repairing defecting units and installing new ones. Lights were replaced by LEDs, and variable speed drives (VSDs) were fitted to dust extraction system fan motors. Active harmonic filtration was applied to melting furnaces in order to prolong the life of nearby equipment. Cooling towers were fitted with drift eliminators to reduce water loss, and cooling tower water supply and fan operation was improved.
Overall, the projects resulted in energy consumption reduction of over 28%.
Financing energy improvements
When making recommendations to industry, the NCPC-SA has repeatedly found that one of the major reasons companies give for not implementing their recommendations is the cost, or investment needed to make the changes. The Atlantis success shows that this is often a misconception, and that maintenance and CAPEX costs can be recouped in surprisingly short timeframes. In this case, the payback period for the energy project improvements is calculated at 0.18 years – just over two months of savings achieved.
Often, a mix of funding sources and modalities can be used. At the Atlantis plant, for example, the changes on the dust extraction systems were done on a shared savings basis, with the contractor being paid for the equipment installed out of the financial savings achieved.
The NCPC-SA also offers technical assistance with financial linkages. “Companies can consider applying for the 12L tax incentive, as an example. Atlantis has definitely qualified for this, by showing evidence of energy efficiency improvements, with verified energy savings. Our energy team can assist with this process, from savings verification to submission of the application.”
“I really want to encourage more companies in this sector to contact us and see if assistance is possible,” concludes Ms Kodisang-Sibanda. “The NCPC-SA is managed alongside the NFTN in the CSIR, and between the two programmes, we sincerely want to support not only the foundries, but all the companies along the metals value chain to become more sustainable and competitive.”
As for Atlantis, Arendse says that the next phase of the journey is to work towards ISO 50001 certification. ISO/SANS 50001 is the international energy management standard, and achieving certification requires evidence of continuous improvement in energy management, through an energy management system aligned to the ISO 50001 guidelines. It is a standard widely adopted in Europe, and particularly Germany, but South African companies have been slow in realising the benefits of the approach, and currently less than 30 companies are certified in South Africa. “The NCPC-SA has already agreed to support us on this phase as well, and we are looking forward to the results.”
The NCPC-SA is a national industry support programme funded by the Department of Trade, Industry and Competition (the dtic) to support industry with the transition to a green economy. The NCPC-SA uses the methodologies of resource efficient and cleaner production to improve efficiencies and competitiveness at industrial plants.
For more information or assistance visit www.ncpc.co.za or email ncpc@csir.co.za
