Power Plant Process Control
Power generation is geared towards maximum cost effectiveness; power stations compete for the right to supply the transmission network based on dollars/electricity unit delivered.
The major cost components in the power station are:
- purchase costs of fuel
- fuel handling and storage
- efficient combustion of fuel
- scheduled maintenance
- unscheduled failures, or plant outages
- disposal of waste products, including treatment of wastes to permit disposal.
Power stations operate in a variety of modes, ranging from "mine mouth" stations, which receive coal from a single nearby source, to remote stations located at load centres, which receive coal from multiple sources. These operating modes also influence stockpile management; a power station close to the mine may receive coal by truck or by overland conveyor and thereby hold minimal stocks, the "just-in-time" approach, whereas a power station reliant on long rail hauls or sea freight to obtain coal may hold larger "live" and "long term" stockpiles. The "just-in-time" operation has little opportunity to blend coals to even out quality variations, whereas the "remote" station can use its stockpiles to advantage.
On-line analysers can monitor the quality of coal feed and waste products, allowing power station operators and management to optimise the performance of the station by making decisions based on knowledge in advance, rather than reacting to changed conditions as they arise.