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How coal-fired power stations are decommissioned
How coal-fired power stations are decommissioned
15 October 2024
Coal supplies just over one-third of global electricity generation according to the Internation Energy Agency and in terms of the global Net Zero Emissions target of 2050, the IEA envisions that unabated coal generation ends by 2040.
The biggest challenge with phasing out coal and thermal gas power stations, is that many countries feel they have no choice as energy demand continues to increase, and cleaner energy sources are not yet in place. The industry globally continues to look at ways to deploy less polluting technologies into thermal stations, including carbon capture utilisation and storage.
In 2023, coal generation still accounted for over 50% of energy generation in Australia (Black Coal 39.3% and Brown Coal 13.4%) and coal-fired thermal power delivered more than 124.5 million GWh of power in 2023.
Stanwell’s coal-fired assets are some of the most efficient and effective in Australia, and we continue to ensure they are maintained and upgraded to minimise impact as the industry transforms. The transition of our coal-fired stations to Clean Energy Hubs is due to be completed by 2035.
Fossil fuels (gas or coal) are fed into power stations and burnt inside a massive water boiler. Each of the boilers at a power station are as high as an eight-storey building (referred to as generating units), and inside, walls of steel tubes extend for the full height of the structure. The heat produced by the burning coal or gas raises the temperature of water flowing through the tubes, to create steam that passes out of the boiler drum. The steam is heated further in the superheaters and fed through high-pressure pipes to the steam turbine. At this point, the steam reaches a temperature of 541°C and a pressure of 17 megapascals (MPa) and this causes the turbine to rotate at 3,000 revolutions per minute (RPM), which ultimately enables the generator to produce electricity.
After steam passes through the turbine, it goes to the condenser. Water circulating through tubes in the condenser cools the steam down and converts it back into water. This water is pumped back to the boiler, and the process of creating steam starts all over again. It is the hyperbolic shape of the towers that creates a natural flow of air from the base of the tower to the top. It’s this air flow that cools the hot circulating water as it falls from the ‘hot pond’ to the ‘cold pond’ at the bottom. The absorbed heat from the water is then released into the atmosphere in the form of fog-like water vapor.
In order to supply the national grid, a transformer steps up the power which is the final step in the process from coal, to steam, to turbines, to the grid.
How coal-fired power stations are decommissioned
15 October 2024
Adrian Hill, Optimisation Lead at Stanwell Power Station (SPS), explains how he helps the station to operate at maximum efficiency each day.
25 June 2024
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