**3. Summary of empirical literature regarding impacts of energy storage technologies**



*The Role of Energy Storage with Renewable Electricity Generation DOI: http://dx.doi.org/10.5772/intechopen.96114*


#### **3.1 Applications of energy storage technologies**

Applications of energy storage technologies are categorized as follow based on their discharging length.

#### **3.2 Storage technologies for power quality applications**

Transient stability and frequency regulation are the part of power quality applications, which require less than a second it means rapid response, but their time may goes up to 10 minutes. Following technologies are used in these applications:

#### **3.3 Flywheel**

It stores energy in the form of rotating mass, because of high efficiency and rapid response these are suitable for frequency regulation [8]. This technology is many advantages like high efficiency, quick response, he life of service, low operation and maintenance cost, stable system, clean technology, but the energy density is low, easy to be self-discharge which is only suitable for short time applications.

#### **3.4 Capacitors**

Super capacitor and superconducting magnetic energy storage are two main carrier of electromagnetic energy storage. This technology has high power density, low maintenance and operational cost, quick response, long life span, and their charging and discharging rate is critical. These are used in transient voltage stability application due to their fastest response among all energy storage devices and energy is stored in the form of electric charges. But, these are redistricted to use in long time duration application due to their low energy capacity; with the advancement and research work their use and density can be increased in grid [8].

#### **3.5 Superconducting Magnetic Energy Storage (SMES)**

The coil of superconducting material store energy in the form of magnetic field, are fast responding energy storage devices, but are restricted to use in short duration discharge time and their total energy capacity [8].
