Why is battery energy storage such a hot topic?

Guest post: Alexandra Goodson, Business Development Manager, ABB Energy Storage Modules

I may be biased, but I think battery energy storage is going to be the next big “game changer” in the smart grid and power industry. Increasing demands for power along with regulations mandating renewable energy generation can lead to instability in the grid. There is constant struggle for utilities to not only maintain but improve their system’s reliability. One way to accomplish this is by having energy that is stored and ready to be dispatched… aka energy storage.

There are many different ways to store the energy. A few popular methods include pumped hydro, compressed air, and my favorite, batteries. Pumped hydro and compressed air are very geographically limited and cannot respond as quickly as batteries, however they are inexpensive when comparing $/kW. Batteries can respond within milliseconds and their prices have been decreasing which is why I think battery energy storage systems will become more prevalent in the near future.

Battery energy storage has become such a hot topic because there are many utility challenges that it can help resolve. These systems can respond within milliseconds to a charge or discharge command. This is ideal when supporting frequency regulation or renewable integration. The solutions provided by battery energy storage boil down to one overall theme: balancing generation and demand. Battery energy storage systems address this in 4 main ways:

- Reducing Variability of Renewable Generation: Renewable generation, particularly wind and solar, is far from consistent and continuous. The sudden dipping and peaking of generation can cause a great deal of stress on fossil generation assets. In addition, the variable power being generated is not appealing for a utility to use. By injecting stored energy, the energy storage module acts as a buffer and smoothes out the renewable generation allowing for easy grid integration.

- Utilizing Renewable Generation Peaks: The generation peaks of renewable generation do not align with demand peaks. Often, renewable energy unnecessarily replaces cheap off-peak generation. By storing excess power during the renewable generation peak, the energy storage module can inject it on to the power grid when demand is high.

- Shaving peak demands: Infrequent and high peaks must be accounted for when sizing transmission, distribution and generations assets. Energy is more expensive during peak times and strains the existing equipment. By charging energy storage modules from the grid during off peak times and injecting it back in to the grid during peak periods, the end user’s peaks are shaved and their loads are shifted. This reduces their charges and ultimately increases their load factor. In addition, utilities can defer new equipment investment.

- Providing infrastructure support as loads increase with electric vehicle usage: Current infrastructure will not be able to handle the large increase in load as electric vehicles become more common. By charging with renewable energy or with grid power during off peak times, energy storage modules can provide power to EV chargers and reduce the demand on the grid

The utility market is always changing and in some applications there are still financial barriers, but battery energy storage systems will become a necessary part of the power grid in the near future and will help make the grid even smarter.