How does inertia affect energy storage?

The inertia response of an energy system limits the rate of change of frequency, known as RoCoF, when a sudden change in load is encountered . Systems such as thermal energy storage and pumped hydroelectric have very little associated inertia and may be thought of as providing slow response energy storage.

How important is inertia to a power system?

The importance of inertia to a power system depends on many factors, including the size of the grid and how quickly generators in the grid can detect and respond to imbalances. A grid with slower generators needs more inertia to maintain reliability than a grid that can respond quickly.

How does energy storage work?

During energy storage, electrical energy is transformed by the power converter to drive the motor, which in turn drives the flywheel to accelerate and store energy in the form of kinetic energy in the high-speed rotating flywheel . The motor then maintains a constant speed.

How does inertial response affect electricity generation?

To accommodate the imbalance between supply and demand due to the drop in generation, the remaining online generators convert their rotational kinetic energy (inertia) into real power generation—referred to as inertial response. This process slows the generators and results in a drop in grid frequency.

How can inertia be maintained?

Summary of Options to Maintain Frequency Stability Inertia can be maintained via operating the grid to ensure the mix of generators online exceeds critical inertia levels.22 Figure 13 showed how as both VG and load vary, power plants are turned on and off, which results in changes in the amount of inertia available.

What is inertia in power plants?

Inertia from rotating electrical generators in fossil, nuclear, and hydroelectric power plants represents a source of stored energy that can be tapped for a few seconds to provide the grid time to respond to power plant or other system failures.