Battery Terminology Glossary

S

SCADA (Supervisory Control and Data Acquisition)

System for monitoring and controlling field equipment (including ESS) from a central location. 

Setpoint

Target value given to the ESS (e.g., charge at 5 MW, hold SoC at 60%). 

SoC Reserve / Operating Reserve

Portion of capacity kept unused to allow for unexpected grid events or to extend life. 

Sodium-Based Batteries

Technologies such as sodium–sulfur (NaS) or sodium-ion batteries, often for grid-scale or high-temperature applications. 

Spinning Reserve / Non-Spinning Reserve

Backup capacity that can quickly support the grid; BESS can provide both due to fast...

State of Charge (SoC)

Percentage of the battery’s usable energy currently stored, typically 0–100%. 

State of Health (SoH)

Indicator of battery aging, usually expressed as remaining usable capacity versus original capacity (e.g., 90%...