What type of reserve must be carried to cover the largest energy contingency?

The type of reserve that must be carried to cover the largest energy contingency is dynamic reserve. Dynamic reserves are necessary to respond to sudden changes in supply or demand on the grid, such as the loss of a large generator or a significant increase in energy demand. This type of reserve can be utilized quickly, typically within a matter of minutes, to stabilize the grid and ensure that there is sufficient energy available to prevent outages.

Dynamic reserves are important in maintaining system reliability because they can be called upon to provide immediate responses to unexpected load changes or generation losses. This capability is crucial for the stability of the electrical grid, particularly in regions where the energy supply is subjected to variability due to renewable energy sources or aging infrastructure.

In contrast, static reserves may not respond as swiftly to changes, synchronized reserves are specifically related to generators that are connected to the grid and ready to generate energy, while reactive reserves pertain to the voltage support in the system rather than direct energy availability in response to contingencies.