Challenges faced during implementation of a compressed air energy savings project on a gold mine / Gerhardus Petrus Heyns

• Main Author: Heyns, Gerhardus Petrus
• Language: en
• Published: 2015
• Subjects: Demand side management; Compressed air systems; Energy savings; Practical challenges
• Online Access: http://hdl.handle.net/10394/15289

MIng (Electrical and Electronic Engineering), North-West University, Potchefstroom Campus, 2015 === Demand side management (DSM) initiatives have been introduced by Eskom to reduce the deficit between the electricity generation capacity and the electricity usage within the country. DSM projects enable Eskom to reduce electricity demand instead of increasing generation capacity. DSM projects are more economical and can be implemented much faster than constructing a new power station. One particular industry where DSM projects can be implemented is on mines. Mines consume about 14.5% of South Africa’s electricity. Producing compressed air, in particular, is one of the largest electricity users on mines. It consumes 17% of the electricity used on mines. The opportunity, therefore, arises to implement DSM projects on the compressed air system of mines. Not only do these projects reduce Eskom’s high electricity demand, but they also induce financial and energy savings for the mine itself. However, during the implementation of a compressed air energy savings project, various challenges arise. These include, among others, operational changes, control limitations, industrial actions and installation delays. All of these can lead to a project not being delivered on time, within budget or with quality results. The purpose of this study is to investigate and address various problems that occur during the implementation of such a compressed air energy savings project. The study shows that although these problems have an impact on the results achievable with the project, significant savings are still possible. Project savings are achieved by reducing the amount of compressed air that is supplied, thereby delivering sufficient compressed air while minimising the amount of compressed air being wasted. During this study, a gold mine’s compressed air network was optimised. The optimisation resulted in an evening peak-clip saving of 2.61 MW. This saving was achieved daily between 18:00 and 20:00 when Eskom’s electricity demand was at its highest. It is equivalent to an annual cost saving of R1.46 million based on Eskom’s 2014/2015 tariffs. When savings from all periods throughout the day are taken into account, the project will produce an annual cost saving of R1.91 million.