The Department of Mineral Resources and Energy (DMRE) has confirmed that five substation sites have been specified by Eskom for the public procurement of battery energy storage systems (BESS) with a combined capacity of 513 MW and a minimum of four hours of storage, or at least 2052 MWh.

A bid submission deadline of 17:00 on July 5 has been set and preferred bidders will be announced about two months thereafter. The projects are expected to be in operation 24 months after reaching commercial close.

The request for proposals (RFP) was launched on March 7, but the documentation is available for download only once a prospective bidder provides confirmation that the R25 000 documentation fee has been paid.

The IPP Office tells Engineering News & Mining Weekly that the payment of a documentation fee has been standard practice for all of South Africa’s independent power producer programmes ever since the launch of the first bid window of the renewable procurement programme in 2011.

There have subsequently been six other renewables bidding rounds, as well as a risk mitigation bid window, through which 11 904 MW of mostly wind and solar capacity has been procured from 134 projects. Not all of the projects have reached financial close, however, and a coal procurement programme was abandoned.

The IPP Office says the total capacity being procured is 513 MW and a minimum installed energy rating of 2 052 MWh has been stipulated, but the actual installed energy rating will be a bidder risk and part of a bidder’s business case.

The programme’s technical parameters have been provided by Eskom Transmission’s system operator, together with transmission grid planning and distribution network planning, which identified the following substation sites:

• Aggeneis 77 MW, at a minimum installed energy rating of 308 MWh;
• Ferrum 103 MW, at a minimum installed energy rating of 412 MWh;
• Garona 153 MW, at a minimum installed energy rating of 612 MWh;
• Mookodi 77 MW, at a minimum installed energy rating of 308 MWh; and
• Nieuwehoop 103 MW, at a minimum installed energy rating of 412 MWh.

All the substations are located in the Northern Cape, and each bid response must be for the full substation energy storage capacity.