How does peak shaving work with battery energy storage systems

Peak Shaving with Battery Energy Storage Systems

Peak shaving with battery energy storage systems (BESS) is a technique used to reduce electricity demand during periods of high consumption, thereby lowering demand charges and reducing strain on the electrical grid. Here’s how it works in detail:

How Peak Shaving Works with Battery Energy Storage Systems

• Energy Storage During Off-Peak Periods: The battery system stores electrical energy during times of low demand or when electricity prices are lower. This energy can come from the grid during off-peak hours or from local renewable sources such as solar panels or wind turbines. Charging the battery when demand and prices are low optimizes cost efficiency.
• Discharging During Peak Demand: When the electricity demand spikes—often leading to higher grid prices and peak demand charges—the battery discharges this stored energy to supply the facility’s load. This reduces the amount of electricity drawn from the grid at peak times, effectively “shaving” the peak from the demand profile.
• Quick Response and Intelligent Control: Battery storage is especially well-suited to peak shaving because it can respond quickly to demand changes. Intelligent control systems, such as Exro’s Battery Control System™, optimize when the battery should charge and discharge, considering factors like state-of-charge, state-of-health, battery safety, and maximizing battery lifetime. This fine control also helps maintain system reliability during faults and prolongs asset life.
• Optimization of Peak Reduction: Advanced optimization algorithms analyze historical load data and real-time consumption patterns to determine optimal peak shaving strategies. This includes selecting the ideal “shave level” — the amount by which the peak demand can be reduced without depleting the battery too quickly or causing unintended power spikes. Statistical methods help ensure that the battery use is maximized efficiently over days or weeks.
• Integration with On-site Generation: BESS can be combined with on-site generation sources like solar panels, wind turbines, or natural gas generators to further reduce grid reliance. Excess renewable energy generated during the day can be stored and used during peak hours, increasing renewable self-consumption and further mitigating peak loads.

Benefits of Battery-Based Peak Shaving

• Cost Savings: Reduces demand charges by lowering peak power drawn from the grid, which is typically billed on the highest 15-minute average power consumption interval. The higher the demand charges, the greater the potential savings.
• Grid Stability and Resilience: By flattening demand peaks, BESS helps reduce the stress on the distribution network and can delay or avoid costly infrastructure upgrades. It also supports overall grid stability, especially as renewable energy sources increase variability in power supply.
• Enhanced Energy Efficiency: Enables better management of energy consumption, especially in energy-intensive facilities like manufacturing, data centers, EV charging stations, and commercial buildings. Batteries allow shifting load away from costly peak times without interrupting operations.
• Support for Renewable Energy: BESS facilitates higher self-consumption of intermittent renewables by storing excess generation for later use, reducing export peaks and dependence on grid energy during peak demand periods.

Practical Applications

• Industrial and Commercial Facilities: Reduce peak demand charges by using stored energy during high load intervals.
• Electric Vehicle Charging Stations: Manage large and sudden spikes in power demand by using BESS to supply energy during simultaneous fast charging events.
• Healthcare, Hospitality, and Educational Institutions: Maintain reliable energy supply while reducing peak power costs.
• Agricultural Operations: Store renewable energy during the day and use it to meet evening demand spikes.

In summary, battery energy storage systems enable peak shaving by charging during low-demand periods and discharging stored energy during peak times to reduce grid power consumption spikes. Intelligent control, optimization algorithms, and integration with renewables maximize cost savings, operational efficiency, and grid benefits.