Balance of Plant (BoP) is an engineering term used in power plants to understand the supporting and auxiliary components in a power plant required to produce energy. These systems offer support to the plant that it needs for running efficiently and in a stable manner. A BoP that is comprehensive can increase the life and performance of the power plant.

BoP is a significant part of power plant operations. Only attending to your boiler and turbine isn’t enough to ensure peak performance of your plant. You can monitor and control the balance of operations in your plant leading to reduced power outages and improvement in overall plant heat rate.

In a power plant, BoP has two components: mechanical and electrical devices.

I)Electrical BOP (EBoP)

Electrical BOP systems are used to regulate, monitor, and protect power plant components by using high, low, medium voltage electrical devices.

II) Examples of EBoP are:

1)Power transformers – These are used to step voltage up or down according to desired levels so that the plant can run smoothly. Transformers work using a number of core windings which transfer electrical energy via electromagnetic induction.

2)Circuit breakers – Automatic power cut-off devices are used for overcurrent and short-circuit protection in power plants. Circuit breakers are vital EBoP devices as they help prevent damage to sensitive components of the power plant.

3)Switchgear – This is a combination of switching devices, fuses, and circuit breakers. Switchgears are used to isolate sections of the electrical systems where a fault has been found. Power plants utilize both high and low-voltage switchgear for overcurrent protection in devices such as transformers, motors, pumps, etc.

4)Electrical busbars – Busbars transmit electrical energy from the generating section to step-up transformers. A busbar is a strip of bare copper metal usually kept inside a panel board or switchgear and enables high power distribution.

III) Mechanical Balance of Plant (MBoP)

MBoP systems are made of non-electrical auxiliary systems necessary to keep power plant operations running optimally. Mechanical balance of plant includes instrument and service air systems, hydraulics, heating and cooling systems. MBoP consists of the following:

1)Fuel Gas Conditioning Systems – These are designed to remove solids, liquids, and aerosols from natural gas.

2)Pressure Reduction Systems – These systems help to reduce gas pipeline pressure safely and to meet the inlet pressure of the gas turbine.

3)Fire protection systems – Fire protection systems prevent and respond to accidental combustion in generating equipment such as combustion cans of the turbines. An alarm goes off which trips the plant when a fire is detected. A procedure is then initiated to extinguish the fire. These systems are a critical component of MBoP systems for the safety of both the assets and personnel on site.

4)Compressed air systems – They provide a continuous supply of compressed air to operate pumps, pneumatic valves, guide vanes, and other equipment in the power plant. Two types of air are required in a power plant – instrument air and service air. Instrument air is used to operate the equipment while service air is used to maintain the plant.