Coal Stock Pile simulation

To safeguard the delivery of energy supply from the Coal Fired Power Stations, a stock back up tonnage of coal is required at a power station. This stock is generally referred to as a Stock Pile (SP) whether measured in tonnage (SPT) or in days (SPD). The Total Stock reflects the stock of coal (in tonnes) at hand, plus the replenishments (such as from stathes [e.g. bunker type] or direct-supply); therefore the Total Stock is equivalent to the SPT. Essentially, the SPD reflects the daily SPD variation on the stock, based on the daily usage and replenishment. The SPD\´s were designed to fulfil most of Eskom energy requirements for the coal PS\´s with a hedging position at acquiring the shortfalls from the short to medium term markets. However, with the growth in ESO (Energy Sent Out), pressure has been put on these markets to deliver the ever-increasing shortfalls. The lack of additional capacity (more power stations) has also been a contributing factor. Hence, the stock pile levels are at risk and careful management of these has become of outmost importance. The Coal Stock Pile Simulator (CSPS) serves as a simulation model which provides "what-if" scenarios and is forward looking. It can provide scenario planning sets for decision making. It is based on the ESO forecasts (including monthly and time-of-use profiles), the Maintenance Plan (for the power stations), the modelled forced outages (UCLF and OCLF), the despatch plan (according to merit order), the international imports (such as Cahora Bassa) and the interrelationships between Eskom\´s Nuclear, Hydro, Pump-Storage, OCGT and Coal PS\´s. Since many of the fundamental inputs are of a stochastic (random) nature and Stochastic Optimisation is still on the drawing board and Universities all over the world, the CSPS is a simulation model and not an optimisation model but can be utilised as a heuristic "optimiser".