Implementation of regulation as an ancillary service in Eskom and the use of Eskom internal web for this service

This paper describes the implementation of regulation as a competitive ancillary service in Eskom. Eskom is presently forming a grid operator business, which is responsible for buying ancillary services and providing a reliable transmission network. The process of defining system performance criteria is described. The total costing of the regulation service to a single coal-fired generator was done using EPRI cost calculations. The performance of an individual generator is calculated along the guidelines of NERC Policy 10, with no allowance for over-control. This performance criterion determines regulation performance and payment to the generator. Over 750 points an downloaded every 4 seconds from the energy management system. System performance and individual unit performance are calculated using standard packages. This information is then made available in near-real time on the Eskom internal web in graphic and tabular form. This allows each generator to continually see its actual performance.