The "BENCHMARK" chronological simulation model: A new tool for better understanding the economic and physical behaviour of electrical generating systems

With some recently developed software, operators and planners can simulate chronologically the hourly commitment and dispatch of a power supply system. This allows them to see if the system is physically capable of supplying the expected load and to estimate the cost of production. Dispatch simulation based on load duration curves is simpler and quicker than chronological simulation, however these curves do not capture the full effect of commitment decisions and technological constraints— for example the limited reservoir capacity of pumped-storage plants and the ramp-rate limitations of base-load thermal units. If such constraints are overlooked, the role of peaking units, storage units, or dispatcher-controlled load management may be estimated incorrectly. The effects of commitment decisions and technological constraints can now be analyzed more precisely with a new computer program called BENCHMARK that will be released this year by the Electric Power Research Institute. As the name signifies, the program is intended to calibrate or benchmark calculations based on load duration curves.