How Pumped Storage Hydropower can Support South Africa’s Energy Transition

This webinar was presented by the Academy of Science of South Africa (ASSAf) on 4 Sept. 2023. It was a collaborative effort between ASSAf, the South African Academy of Engineering (SAAE) , and the South African Institution of Civil Engineering (SAICE). Read more about ASSAf at: https://www.assaf.org.za/ Invitation to webinar: https://www.assaf.org.za/2023/08/17/h... PROGRAMME 00:00:00 Introduction 00:00:42 Welcome and Introductions: Prof Himla Soodyall (Executive Officer, ASSAf) 00:03:24 Programme Coordinator: Prof Pat Naidoo (Vice Chairperson: STEMI; ASSAf; SAAE) 00:05:07 How pumped storage hydropower can support South Africa's energy transition Speaker: Prof Mike Muller (Wits School of Governance; SAAE Fellow) 00:15:19 Palmiet and Steenbras: the specific example of Western Cape Speaker: Dr Mike Shandisan (Honorary Fellow of SAAE; consultant at Zutari) 00:29:33 Pumped storage issues in the energy transition Speaker: Prof Mike Muller (Wits School of Governance; SAAE Fellow) 00:55:06 Discussion BACKGROUND To address South Africa’s electricity crisis, the immediate priority is to improve the reliability of existing coalfired generators and build new generation. Much of the new generation will come from intermittent renewable sources such as solar and wind. Substantial investments will have to be made in transmission and energy storage to integrate these new sources into the national electricity system. While the need for new transmission lines has been recognized, the storage requirements are less well understood. Current proposals are for short term storage to allow a few hours of ‘load-shifting’ from periods of peak generation to peak demand. However, storage is also needed to balance longer term supply variations, maintain grid stability and provide “black start” capabilities in the event of grid failure. Globally, conventional and pumped hydropower are already playing this role effectively and cost-efficiently, making an important contribution to carbon-free electricity generation. While South Africa’s conventional hydropower potential is limited, our 3 000MW of pumped storage is already playing an important role. Existing pumped storage plants were developed to use surplus off-peak power from coal and nuclear stations to meet peak demands. They store enough energy to generate at full capacity for up to 15 hours, helping to balance the variable supplies from solar and wind sources, over a full week. As the proportion of intermittent renewable generation increases, pumped storage can continue to play an important part in SA’s electricity system. However, as will be explained in the seminar, planning and construction of pumped storage installations is a lengthy process. If South African wants to avoid dependence on high-cost, imported ‘plug and play’ grid-scale batteries, implementation needs to start sooner rather than later. BRIEF BIOGRAPHIES Prof Mike Muller, PrEng, is a SAAE Fellow and visiting adjunct Professor at the Wits School of Governance. He has served as a National Planning Commissioner, and Director General of water and advised national and regional organisations on water, energy, climate and sustainable development issues. Dr Mike Shand is an Honorary Fellow of SAAE and a consultant at Aurecon. His achievements include engineering projects, particularly in the fields of water resource planning, design and management and dam design and construction.