Quantification of budget improvement methods for utilities at platinum mines in South Africa

Utility costs for platinum mining operations are considered fixed costs. It comprises water and electricity costs. Business reviews occur annually whereby, the utility quantities and associated costs are forecasted in the form of an energy, water and utility cost budget. The purpose of this study is to review the literature to find energy budget improvement methods. A method for evaluating the impact of the budget improvements was constructed. The case studies aimed to isolate the effect of different methods by reducing uncertainties to determine % improvement of the applied methods. The method improvements that were focused on were: • Reduced energy costs on public holidays. • Budget accuracy of using historic monthly data compared to an hourly daily consumption profile for energy. • Budget accuracy of using historic monthly data compared to an hourly daily consumption profile for cost prediction. • Effect of adjusting for production plan changes. • Budgeting with different methods for different utilities compared to a grouped estimation from historic data. • Having the option to escalate time-of-use tariffs individually. The public holiday consideration lowered the budget by 0.85 % for ventilation, 0.8 % for mining and 0.6 % for the compressed air utility. The energy prediction of the official budget for compressed air was more accurate compared to using historic monthly data. It lowered the budget error % compared to actual consumption by 2.5 %. The cost estimation from the daily consumption profile did not differ from estimating the compressed air cost with historic data. The cost estimation did not vary since the billing is done with TOU consideration. Adjusting for production changes increased the range of budget variation compared to a budget that made no production adjustment. The unadjusted budget overestimated the energy by 0.9 %. The production adjusted budget overestimated the energy consumption by 4.2 %. Budgeting with three different methods compared to a single method for a grouped total reduced the budget variation with 3 %. Having the ability to escalate each TOU tariff individually reduced the range of the budget variance. The budget that assumed even escalation across all TOU periods had a range of -11.9 % to +3.2 %. The detailed budget had a range of -3.2 % to +0.4 %. This study had limited data and requires further investigation. The study ultimately provides insight into the practical application of budget improvement methods and its impact on the annual budget accuracy.

Grantor dc:publisher

Stellenbosch : Stellenbosch University

Year dc:date.issued

2026

Author dc:creator

• Conradie, Shana

Advisors dc:contributor.advisor

• Gous, A. G. S.
• Schutte, C. S. L.

Language dc:language.iso

en

Repository record dc:identifier.uri

https://scholar.sun.ac.za/handle/10019.1/135697

OAI identifier oai:identifier

oai:scholar.sun.ac.za:10019.1/135697