Auxiliary power supply system of energy storage cabinet

What is auxiliary power supply system?

The purpose of auxiliary power supply systems is to cater for the necessary energy for the operation of primary and secondary devices at the substation. The auxiliary power systems are normally divided in two categories, namely the AC system and the DC system (s).

Who is responsible for auxiliary power supply?

When an external auxiliary power supply is required, project owners or their EPC (engineering, procurement and construction) contractors are typically responsible for designing, furnishing and installing the auxiliary power supply circuit. This includes auxiliary power transformers, switchboards and cables.

What is the rated voltage of auxiliary power supply?

For example, the rated voltage of the auxiliary power supply might be 400V, 480V, or 208V. The circuit must also be sized based on the peak auxiliary load of the selected BESS product and the specific project configuration. Each BESS product has a unique auxiliary load design and peak auxiliary load.

What are the requirements for auxiliary power supply circuits?

The auxiliary power supply circuit must be designed to meet the BESS product's technical requirements, which vary by product. For example, the rated voltage of the auxiliary power supply might be 400V, 480V, or 208V. The circuit must also be sized based on the peak auxiliary load of the selected BESS product and the specific project configuration.

What is the electricity cost for auxiliary loads?

The electricity cost for auxiliary loads depends on the energy consumption (kWh) and the pricing structure set by independent system operators or utilities. For example: In ERCOT, the BESS auxiliary load must be metered separately from energy used for battery charging and is charged at the retail rate.

What auxiliary loads are needed for a Bess project?

Fire safety systems, such as fire alarms, control panels and gas ventilation systems (if present). These auxiliary loads are essential for ensuring the safe and efficient operation of BESS projects. Therefore, providing a reliable power supply for these auxiliary loads is crucial.