Non-Dispatchable Generators

Non-dispatchable generators do not submit offers to provide energy; instead, they submit estimates or forecasts of energy production. They agree to be paid the current market price when they generate electricity, regardless of what that price might be.

There are two types of non-dispatchable generators - self-scheduling and intermittent.

An example of a self-scheduling generator is a generator running on hydraulic power from a small river. If the generator has no ability to store the water, it might not always be able to provide energy in response to IESO dispatch instructions. This type of generator would register as self-scheduling. Self-scheduling generators submit schedules to the IESO indicating the amount of energy they will be providing for each hour of the day. Self-scheduling generators are restricted by size - in order to be classified as self-scheduling, a generator must be rated between 1 and 10 megawatts.

Intermittent generators are even less able to forecast the amount of energy they will generate. They operate intermittently as a result of factors outside the owner’s control. For example, a windmill is classified as an intermittent generator because it must rely on wind for its operation.