What are the benefits of a battery energy storage system?

A BESS provides uninterrupted backup power during grid outages, enables energy arbitrage and peak shaving to reduce tariffs, and enhances savings from solar systems by storing excess energy for later use.

How does battery storage help with peak shaving?

By charging batteries during off‑peak or solar generation times and discharging them during peak tariff periods, a BESS reduces peak demand charges and overall energy costs.

Can battery storage systems integrate with solar installations?

Yes, they store solar-generated energy for use when the sun isn't shining, increasing self-consumption and reducing grid dependence.

Which battery types are typically used?

Most systems use lithium‑ion batteries (especially Li‑phosphate) for high performance and safety, though flow, sodium‑ion or liquid‑metal batteries may also be used depending on project needs.

Is battery storage cost-effective in South Africa?

Yes—peak tariff arbitrage, solar self-use, load‑shedding resilience, and potential financing models like PPAs make BESS economically attractive, especially amid rising Eskom tariffs.

Battery Energy Storage Systems | Peak Shaving

Name: Forest Energy Battery Storage System
Brand: Forest Energy
Availability: InStock

Understanding the Difference Between Peak Shaving and Energy Arbitrage: Battery Storage Strategies for Smarter Energy Use

South African businesses are under pressure from rising electricity tariffs and demand-based billing structures. Battery energy storage systems offer powerful ways to reduce energy costs and manage demand more effectively. Two key strategies, namely peak shaving and energy arbitrage, are often mentioned together but serve very different purposes. Understanding the distinction is essential for unlocking real value.

1. Peak Shaving

Objective: Minimise your highest electricity demand (kVA) to reduce demand charges.

Utilities such as Eskom and City Power typically bill based on your single highest kVA demand in a month – even if it lasts only a few minutes. This can result in substantial fixed charges that don’t reflect your average usage.

Example: If your plant hits 500 kVA for just 15 minutes, perhaps during a Monday morning startup, you’re billed for 500 kVA all month. At R290/kVA, that’s R145, 000, even if your regular usage is much lower.

Solution: A battery energy storage system can discharge at the right moment to limit that peak, reducing it to 400 kVA and saving R29,000 in demand charges.

Best For: Facilities with infrequent but high surges, such as factories, cold storage warehouses, or sites with heavy startup loads.

2. Energy Arbitrage

Objective: Reduce your energy cost by shifting when you consume grid electricity.

Energy arbitrage involves charging your battery when electricity is cheap, either during off-peak periods or using excess solar PV, and discharging it when tariffs are high.

Example: Charge the battery during low-tariff hours, such as R1.18/kWh, or from R0 solar. Discharge during evening peak tariffs, such as R6.89/kWh). This saves R5.71/kWh, significantly lowering your overall energy spend over time.

Best For: Businesses on time-of-use (TOU) tariffs, especially those with solar installations that can charge the battery energy storage system during the day.

Feature	Peak Shaving	Energy Arbitrage
Focus	Reduce demand charge (kVA)	Lower energy cost (kWh)
Trigger	Brief, high load events	Daily tariff variation
Usage Pattern	Occasional discharge during peaks	Daily charge/discharge cycle
Impact	Lowers fixed charges	Cuts variable energy spend

Smarter Systems Combine Both

The most effective battery energy storage systems combine both strategies; they shave peak usage to avoid punitive demand charges and optimise timing to reduce daily energy costs.

For businesses navigating complex tariffs and sharp usage patterns, combining these strategies offers better financial and operational control.

Optimise Energy Costs with Forest Energy’s Battery Energy Storage Systems

Interested in optimising your energy use with battery energy storage systems? Forest Energy can design a tailored solution that meets your demand and cost-saving goals.

Battery Storage Strategies for Smarter Energy Use