Peak shaving targets the reduction of a facility’s or grid’s highest instantaneous demand to lower demand charges, delay infrastructure upgrades, and reduce reliance on peaker plants. This article outlines peak shaving, available energy storage options, and compares load shifting with peak shaving to help buyers, financiers, and engineers select the most suitable solution.
TL;DR / Summary
Peak shaving is the targeted reduction of a facility’s or grid’s highest-demand periods by using stored energy to lower peak load and avoid costly demand charges. Battery energy storage systems (BESS) enable precise, fast peak shaving and can be revenue‑stacked with other services; their value depends on the demand‑charge structure, market rules, required duration, and degradation. Procurement must prioritize proven safety (BMS/SCADA), Energy Management System (EMS) optimization logic, and insurability. Project finance needs clear, conservative revenue stacking, degradation models, and test reports; engineers need demonstrated thermal management, signed firmware, and control integration.
Sizing is critical in peak shaving strategy. It involves determining the optimal capacity and power output for an energy storage system or generation asset to effectively reduce peak demand charges while remaining cost-effective. Typical sizing guidelines are 15–60 minutes of discharge for demand-charge reduction and 2–6 hours for replacing peaker plants or participating in capacity markets. Sizing should be validated using historical load profiles, worst-case single-day peaks, and duty cycle sensitivity. Combining peak shaving with other grid flexibility services maximizes reliability and revenue from energy assets.
Grid Flexibility Services
These are actions and tools that enable electricity grids to respond to fluctuating supply and demand in real time. These mechanisms can manage energy generation, consumption, and maintain grid stability. They can be technological, revenue-based, or a combination of both.
Let us introduce a few core examples:
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Capacity Compensation: Financial payments provided for the availability of resources, such as batteries or standby power plants. This mechanism ensures the satisfaction of peak demand and long-term resource adequacy. It compensates providers for their flexibility in increasing power supply or reducing demand during periods of system stress.
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Renewables Power Arbitrage: Balancing of energy supply and revenue in a nutshell. The methods for storing surplus energy during times of high supply (and low price) and discharging it when demand is high, and output is low. It offsets the volatility of renewable energy and improves utilities’ profitability.
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Frequency Regulation: An ancillary service (specialized function that helps maintain grid stability and reliability) that maintains the grid’s frequency (e.g., 50 Hz or 60 Hz) within strict limits by instantly balancing supply and demand. It uses fast-acting assets such as battery storage to absorb or inject power. Within seconds, energy imbalances can be rebalanced.
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Load Shifting & Peak Shaving: Load Shifting involves moving energy consumption from peak periods to off-peak times (e.g., using smart devices to charge electric vehicles at night). Peak Shaving is the practice of reducing maximum demand during high-load periods to prevent grid congestion and reduce stress on infrastructure.
More on Peak Shaving
So, peak shaving is the practice of reducing the highest electrical demand (kW) of a site or grid, at a given moment, by displacing grid-supplied power with stored or onsite generation during temporary high‑load. The main objective is to reduce utility demand charges, defer or avoid hardware upgrades (e.g., transformers or distribution parts), reduce reliance on peaker plants, and improve grid stability.
How peak shaving differs from load shifting
Peak shaving targets short-duration, high-power events to reduce maximum demand (kW).
Load shifting, so-called energy arbitrage, moves energy consumption across time to
capitalize on price differences (kWh), typically over multiple hours.
A BESS can perform both actions. The choice depends on cost aspects such as tariff structure and market participation rules.
How BESS is Used for Peak Shaving
BESS provides fast energy dispatch (in milliseconds), enabling precise clipping of demand spikes because it is:
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Modular and scalable: capacity can be adapted to specific site needs.
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Multifunctional: peak shaving can be used in combination with frequency regulation, demand response, and arbitrage (i.e., revenue stacking).
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Avoiding infrastructure spending: upgrades can be postponed, and connection capacity fees can be reduced. Great for utilities and customers!
Role-Specific Priorities
Your best peak-shaving strategy and associated technology largely depend on your priorities. Study Table 1 below for questions to ask before any investment, depending on your role. To achieve a solution that satisfies multiple priorities and pleases the entire project team, you should liaise with your cross-functional teams and colleagues with different responsibilities to reach a suitable compromise.
| Role | Priority | Suggested Questions |
|---|---|---|
| Buyer | Price vs. performance, i.e., bankability of technology | Is EMS proven for peak shaving? Are warranties throughput‑explicit? Are safety tests available? |
| Project Finance Officer | Revenue predictability | What are conservative revenue scenarios? Are independent test reports and insurance letters provided? |
| Engineering Staff | System integration, reliability, and safety | Is BMS signed firmware present? Are thermal systems and fire mitigation verified? Can SCADA/EMS integrate with site controls? |
Table 1: Role-focused evaluation checklist. The questions you should focus on depend on your strategic role within the project.
Sizing a BESS for Peak Shaving
By sizing (of BESS for peak shaving), we refer to adapting your energy storage or onsite generation based on your expected peak demand. Accurately sizing your BESS for Peak Shaving is important to ensure optimal peak shaving and thus steady distribution.
Check out our step-by-step guide below for how to accurately size your Peak Shaving actions with BESS:
- Gather historical load data: 15–60 second resolution preferred for at least 12 months.
- Identify target peaks: the single highest event, the top 10 monthly peaks, and seasonal peaks.
Choose objective: reduce billed peak (monthly max), limit transformer loading, or replace peaker dispatch. - Compute required power (kW) and energy (kWh): power = peak reduction target; energy = area under curve of peak clip duration × safety margin.
- Simulate: with EMS logic, including state‑of‑charge (SoC) constraints, round‑trip efficiency (RTE), and reserve margins.
Useful tips!
| Tip | Rationale | Rule of thumb |
|---|---|---|
| Demand‑charge clipping | Targets short, high kW peaks that increase monthly bills; minimizes energy capacity required | 15–60 minutes usable discharge → ~0.25–1.0 MWh per MW clipped |
| Peaker replacement | Covers multi‑hour dispatch windows or ISO product durations; enables capacity revenue and reduces peaker runs | 2–6 hours usable energy (size to market/ISO duration) |
| Backup reserve | Preserves critical‑load availability during outages; requires a reserved SoC that reduces usable capacity for peak shaving | Define outage duration + minimum SoC (e.g., 10–30%); add 20–50% energy above peak‑shave sizing |
| Load shifting (arbitrage) | Shifts kWh from high to low price periods; needs a longer duration to capture energy spreads | 2–8 hours discharge (market/tariff dependent) |
| Ancillary | Provides high‑value, short‑duration, high‑power events; increases cycle demands and thermal requirements | High power rating with 5–30 minutes of energy reserve per event |
| Multi-service (hybrid) | Revenue stacking across services; must define EMS preemption to avoid double‑counting and protect warranties | Start with a peak‑shave baseline and add 20–100% energy margin per additional service |
Benefits of Combining Peak Shaving with Other Grid Flexibility Services
As mentioned, grid flexibility services can be either technology-based or revenue-based. They can also be a combination of both. Whereas peak shaving is not a type of revenue stacking in itself, but is enabled by technological mechanisms, it can be combined with purely revenue-based strategies. Combining it with other services allows the asset to generate revenue while reducing costs.
In summary, peak shaving is a core component within a broader revenue stacking strategy.
Common stacks
| Stack | Benefits |
|---|---|
| Demand charge reduction + energy arbitrage | Lower cost: Demand charge reduction targets the highest 15-minute usage peak of the month, which often accounts for ⪬50% of a company’s energy bill. Generated profit: Energy arbitrage generates profit by charging during low-price periods (e.g., at night or during periods of high renewable output) and discharging when prices are high. Operational Flexibility: Arbitrage can be performed during any daily price fluctuation. Demand charge reduction ensures that the battery is ready for the facility’s specific peak events. |
| Peak shaving + ancillary services (e.g., frequency regulation, spinning/non‑spinning reserves) | Increased Grid Stability Revenue: Fast-responding batteries earn premium payments by balancing the grid in real time (so-called Frequency Regulation/FCR). Emergency Backup: Potential of earning from standby fees by acting as spinning or non-spinning reserves. The former are online, synchronized with the grid, and ready to respond within 10 minutes. The latter are made up of offline generators or so-called curtailable (switchable on/off or reduced) loads that can start up and provide power in >10>30 minutes. Infrastructure Deferral: Shifting peak loads reduces stress on local transformers and wiring, potentially delaying expensive utility upgrades. |
| Peak shaving + capacity market participation or demand response | Guaranteed Revenue: Capacity market participation pays assets simply for being available to provide power during the grid’s most critical hours of the year. Event-Based Incentives: Demand Response (DR) programs provide high-value payments when the facility reduces its grid draw during specific utility events, so-called utility calls, or emergencies. Reliability & Resilience: Combining these two mechanisms ensures that a facility remains operational during grid-wide stress, whilst it is paid to reduce its reliance on the system temporarily. |
Pieces of Advice
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Prioritize contracted revenue streams (fixed-capacity payments) over opportunistic markets.
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Avoid double‑counting the same capacity across simultaneous services; specify arbitration priorities.
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Include RTE, per-cycle degradation, and availability obligations in lifetime revenue models to provide a holistic view of future costs and revenue.
