Modernising underground compressed air DSM projects to reduce operating costs

Compressed air is an energy intensive utility that is frequently used in the deep level mining industry. Most compressed air networks are designed to ensure ample compressed air supply to consumers. This has created the foundation for existing compressed air energy saving projects on deep level mines. Over the past decade, electricity costs in South Africa increased drastically. As a result, the need to further improve and optimise existing Demand Side Management (DSM) projects with modern technology and expertise has become more feasible. This study therefore provides and evaluates a solution to reduce the electricity consumption and operating costs of a compressed air system on a deep level mine. This was achieved by modernising and improving an existing underground compressed air DSM project. It was found that the improvements realised significant additional electrical energy savings. This resulted in ample cost savings to justify the implementation of the improvements.

1. Introduction

With the drastic electricity cost increases South Africa experienced over the past decade (approximately 400% increase on the Eskom Megaflex tariff structure from 2004–2014), electricity has escalated to one of the main expenses in the mining sector [1], [2]. For this reason strategies to reduce electricity usage became more prominent from an electricity consumer perspective.