NEW SPANISH REGULATION: PRACTICAL CONSEQUENCES IN GENERATION SCHEDULING (POWER DELIVERY'97 : Power Delivery in a Changing Environment. Madrid, Spain. June 17-19, 1997)

The paper submitted here proposes a procedure for generation scheduling within the competitive framework set out for the Spanish Electric System as of 1998, where an institutional organization based on two independent operators has been chosen, one in charge of the wholesale market operation and the other one responsible for the production and transmission system operation.

Within the framework of the new regulations, generators must bid their production to the Market Operator, who will match sale orders for power and demand announced by purchasing players and will establish the marginal price for each scheduled period, at which all the system production will be paid. Afterwards, the System Operator will adjust the schedule drawn up by the Market Operator to the real operating conditions of the system, taking into account operational needs regarding frequency regulation and voltage control, transmission constraints and the agent's unavoidable errors in estimates.

The proposed scheduling procedure is therefore developed in two phases, in which two operators successively act without interfering with each other, notwithstanding the existing interrelationship. The key to this procedure lies in the establishment of clear market operating principles which assure the bidding freedom of the agents, the absence of discriminatory treatment of the bids, and the ready comparison of results. The procedure proposed implies respecting the return margins which may be obtained by generators in the power market, so that any change introduced by the System Operator be carried out without changing the above mentioned margin to its players, who have already had their bids included in the first phase, that of market matching. Finally, it sets out the respective optimization problems which must be faced by both operators, and proposes an effective mathematical method of solution.