Greener Upgrades blog series #10

Powering motor starts with Battery Energy Storage Systems (BESS)

Motor start challenges

In industries such as manufacturing and construction, motor starts can create significant electrical load spikes that impact power stability and equipment efficiency. Integrating a Battery Energy Storage System (BESS) can offer substantial benefits for managing these spikes, ensuring reliable operations and enhanced generator performance.

Motor starts often cause a brief but high spike in electrical load. Without proper management, this can lead to:

Power instability: sudden load spikes can cause fluctuations in power supply.
Generator reliability: generators may run inefficiently, especially when frequently dealing with these spikes.
Increased emissions and fuel consumption: generators operating at inefficient capacity are less efficient, leading to increased fuel and emissions.

Sectors

Manufacturing: Motor starts are common in various machines such as conveyors or overhead cranes.
Building Services & Construction (BS&C): In construction, where power needs fluctuate for energy intensive equipment such as hoists or tower cranes, a BESS ensures reliable motor starts and can reduce the necessity for oversized generators.

The 150th Open, St Andrews, 10-17 July 2022

Load management

A BESS can absorb the initial surge of power required for motor starts, which smooths out the demand on the primary power source. This ensures a stable power supply and prevents sudden spikes from affecting overall power quality. With a BESS managing peak loads, a smaller generator can be used to power the base load of operation.

Generator optimisation

By handling the load peaks, a BESS allows generators to operate more efficiently. Generators avoid running at low loads or being oversized for short peak periods, both of which can be inefficient and cause unnecessary wear.

Enhanced generator efficiency and reliability

A BESS enables a smaller generator to run within their optimal performance range more consistently, less operation at low loads reduces wear and tear on the equipment.

Emission and fuel reduction

Operating generators at optimal loads minimises emissions, leads to lower fuel consumption and reduced operational costs.

Using Stage V certified generators

Incorporating a BESS enables the effective use of stage V generators that need to consistently operate at loads above 30%.

Example scenario

A manufacturing facility has a new conveyor system that requires a peak power of 320 kW for motor starts 20-30 times daily. With operations running 24/7, the facility initially relies on a temporary power solution until mains power is available in 8-10 months.

Traditional solution:

Using a 500 kVA generator constantly to handle peaks, leading to inefficiency and high fuel consumption.

Greener solution:

using a 200 kVA generator, paired with a 150 kVA / 75 kWh BESS, allowing the battery to handle the motor start surges. After the motor starts, the generator operates at approximately 75% load, optimising fuel consumption and maintaining efficiency.

Conclusion

Integrating a BESS for motor starts not only improves generator performance and efficiency but also offers significant environmental benefits. By managing load spikes effectively, BESS ensures more stable power delivery and helps to reduce fuel and emissions, contributing to a more sustainable and efficient operation.