Difference between 4 hours energy storage and 2 hours energy storage

What is the difference between a 2 hour and 4 hour battery?

Consider a two-hour and four-hour battery with the same storage capacity in MWh, say 8 MWh. The four-hour battery will have a power rating of 2 MW and the 2-hour battery will have a power rating of 4 MW. Both can deliver energy for two hours, but the four hour battery will only be able to discharge half its energy storage capacity in that time.

What is storage duration?

Storage duration is the amount of time storage can discharge at its power capacity before depleting its energy capacity. For instance, a battery with 1 MW of power capacity and 4 MWh of usable energy capacity will have a storage duration of four hours.

Should energy storage be more than 4 hours of capacity?

However, there is growing interest in the deployment of energy storage with greater than 4 hours of capacity, which has been identified as potentially playing an important role in helping integrate larger amounts of renewable energy and achieving heavily decarbonized grids.1,2,3

Can 4 hour storage meet peak demand?

The ability of 4-hour storage to meet peak demand during the summer is further enhanced with greater deployments of solar energy. However, the addition of solar, plus changing weather and electrification of building heating, may lead to a shift to net winter demand peaks, which are often longer than can be effectively served by 4-hour storage.

What are the different types of energy storage durations?

The three main categories of durations are short, medium, and long, with each serving specific needs in the evolving clean energy space. It’s become clear in recent years that our energy storage needs will need to be met by more than one storage type, and a wide range of discharge durations will be required.

What is long duration energy storage?

Long duration energy storage, as currently defined in the industry, refers to systems that can provide power for 6 to 1,000+ hours of rated discharge. However, it's time to move away from this imprecise term and describe storage based on the functions it can provide.