Procuring load curtailment for grid security in Alberta

ESBI Alberta Ltd. (EAL) is Alberta´s independent transmission administrator (TA) and is responsible for the procurement of system support services also known as Ancillary Services. This presentation looks at procurement of system load as an ancillary service that can be curtailed by a system dispatcher or tripped using protective relaying. The Alberta electric system has approximately 9000 MW of generation of which 7500 MW is used to satisfy system demand and the remainder is used to serve `behind the fence´ load that is not directly served by the Alberta transmission system. Alberta has five types of services that loads can offer into, where the load is used to provide system security or assure adequacy of supply to customers in Alberta Power systems have historically treated load with the `obligation to serve´ mindset and as we move into more competitive environments, some loads now have the mindset of `opportunity to provide´ ancillary and energy services