Education Centre

What is electricity?

Electricity can be defined as the flow of electric charge.

How is electricity generated?

Electricity is not a commodity that can be stored, therefore, the generation of electricity and to make it available for use involves the uninterrupted conversion of other forms of energy to electrical energy.

The source of electricity starts with fuel as the raw material. The chemical energy stored in any fuel can be accessed through combustion, in the form of heat energy. 

How is electricity generated by PowerGen?

PowerGen utilizes natural gas, which is a hydro-carbon (CH4), known as methane as the primary source of energy. The heat energy is then absorbed in an engine, which can convert it into Mechanical Energy. 

PowerGen uses both steam turbines and gas turbines for this conversion. The steam turbine cycle consists of:

  1. Boiling the purified water in a Boiler to produce steam at high pressure and temperature.
  2. Using the high pressure high temperature steam to drive a Steam Turbine.

The Gas Turbine Cycle consists of:

  1. Compressing atmospheric air in the Compressor section of the machine.
  2. Burning fuel in the compressed air, in the Combustion section of the machine
  3. Using the high temperature products of the combustion, to produce mechanical energy of rotation in the Turbine section of the machine.

The Combined Cycle arrangement utilises the combination of the gas turbine cycle and the steam turbine cycle, in a single power plant arrangement. The gas turbine exhaust gases are used as the energy input into a Heat Recovery Steam Generator (HRSG) which produces steam for the steam turbine.

The Combined Cycle Plant, therefore, represents the most fuel-efficient arrangement of power generation at PowerGen.