How BESS Reduces Maximum Demand Charges
BESS reduces maximum demand charges by discharging stored energy during peak demand periods, lowering the power drawn from the grid and the highest demand recorded during the billing cycle.
What is maximum demand?
Maximum demand is the highest level of electricity demand recorded during a billing period, usually measured in kilowatts (kW). If a factory normally uses 1,000 kW but spikes to 1,500 kW when several machines start together, the bill may include charges based on the 1,500 kW peak — even if it only happens briefly. This is why maximum demand management is so important for C&I users.
Why maximum demand charges matter
Demand charges are linked to the highest power draw, not just total consumption. A business may already use energy efficiently, but sudden spikes can still make the demand charge high. Common causes include:
- Large motors starting
- Air-conditioning and chillers running together
- Compressors operating at peak load
- Production machinery starting at the same time
- Cold storage refrigeration cycles
- EV charging and data-centre cooling
How BESS reduces maximum demand
During normal periods the BESS charges from solar or the grid. When demand approaches a peak, it discharges to support the site, so less power is drawn from the grid. For example: without BESS the site may draw 1,500 kW; with BESS discharging 300 kW, the grid only sees 1,200 kW. This is called peak shaving.
Why BESS beats manual load control
Some businesses try to reduce demand by switching off equipment or staggering operations, but this can disrupt production and requires supervision. BESS provides an automated solution: with an EMS, it detects when demand approaches a threshold and discharges automatically, making demand management more consistent and reliable.
BESS with solar for demand reduction
Solar reduces daytime consumption, but a cloudy moment or sudden load increase can still create a spike. When BESS is paired with solar, it stores excess solar energy and discharges during peaks. Solar reduces total energy imported; BESS reduces the peak demand drawn — together providing both energy and demand savings.
Frequently Asked Questions
Yes. BESS can discharge during peak demand periods to reduce the power drawn from the grid.
Peak shaving means reducing demand peaks by using stored energy instead of drawing all power from the grid.
Yes. Solar reduces energy consumption, while BESS helps reduce demand peaks.
Electricity bills, maximum demand history, load profile, solar data and operating schedule are usually required.
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