Solar and Energy Storage Terms

The practice of stacking multiple revenue streams, such as demand reduction and grid services, to maximize total economic value.

The number of full charge and discharge cycles a battery can complete before its usable capacity falls below a specified threshold. Temperature, discharge depth, and cycling behavior all influence cycle life. Manufacturers typically rate cycle life under controlled testing conditions. 

A peak-shaving strategy that monitors a site’s metered demand against a defined threshold and discharges the battery whenever demand rises above that limit. When site-net-PV demand falls below the charging threshold and the battery has available capacity, the system recharges to ensure sufficient energy is stored for future peak events. This strategy focuses solely on managing a single Time-of-Use period and supports both PV charging and unrestricted charging configurations. 

Programs that incentivize customers to reduce or shift load in response to grid conditions or price signals. 

The percentage of a battery’s capacity that has been used relative to its full capacity. Higher depths of discharge generally shorten battery life. Managing discharge depth helps preserve long-term performance.

An external instruction from a utility, market operator, or VPP operator directing assets to charge, discharge, or hold.

A dispatch approach used by Acumen AI within ETB Controller that optimizes battery operation in real time by evaluating site load, PV forecasts, pricing data, and program requirements to determine the most cost-effective dispatch each interval. Unlike fixed or schedule-based strategies, Dynamic Economic Dispatch adapts dispatch decisions in response to changing conditions. It reflects the AI-driven decision-making layer within the controller rather than a standalone control strategy.

An energy management strategy that shifts energy consumption by charging during lower-priced periods and discharging during higher-priced periods to capture value from price variability. Energy Arbitrage can be applied across any pricing structure where energy costs fluctuate, including time-of-use (TOU) rates and real-time or dynamic pricing, while avoiding the creation of new site demand peaks. 

A control system that determines when and how an energy storage system charges, discharges, or remains idle using inputs such as load, solar production, and utility pricing. The EMS operates above the battery management system (BMS) and power conversion system (PCS) to optimize operation and balance performance, economic value, and battery longevity. Energy Toolbase’s EMS, ETB Controller, makes site-level economic and operational decisions to optimize dispatch at a given site.

A peak-shaving strategy that uses a single user-defined threshold to determine when discharging should begin. The system discharges above the threshold and remains inactive below it. This strategy provides predictable and straightforward peak shaving behavior.

A fast-response grid service where batteries charge or discharge to help maintain grid frequency within required limits.

A dispatch strategy that discharges the battery based on an external signal from a specific piece of equipment monitored by dedicated current transformers. The goal is to directly offset that equipment’s load by shaving it down to a defined Threshold whenever the signal rises above the Minimum Signal value. This strategy supports configurations that allow charging from PV or unrestricted charging. 

A control mode where operators specify exactly when the system should charge, discharge, or hold a specific state of charge, and the controller executes those instructions as written. This mode is used when a project requires predictable, operator-controlled behavior, such as contractual dispatch windows, fixed event participation, or site-specific operational requirements. 

A fixed timetable that defines when an energy storage system should charge, discharge, or remain idle. It relies on user-selected operating modes and does not adjust to real-time conditions such as changing load, pricing, or solar production. Within ETB Controller, operating schedules provide predictable, programmatic control over system behavior when dynamic optimization from Acumen AI is not required. 

The bidirectional inverter that manages power flow between a battery’s DC energy and the site’s AC electrical system. It enables both charging and discharging by converting power in either direction and controls battery behavior based on available capacity, metered data, or external signals. The PCS performs the core electrical interface functions of an energy storage system and operates differently depending on whether the system is configured as AC-coupled or DC-coupled.

A dispatch mode that charges or discharges the battery at a fixed power level defined by the operator,  continuing until the battery reaches a target state of charge or a protective limit. At that point, the system holds power at zero to maintain the desired state. 

An Acumen AI strategy that combines peak shaving and energy arbitrage into a single operating approach. To ensure reliable peak shaving, the system maintains a higher state of charge as a form of “insurance,” which can limit the battery’s ability to discharge deeply for arbitrage. This approach prioritizes demand reduction while still capturing pricing opportunities when sufficient capacity is available.