Share
clock Created with Sketch.
28/08/22
19:02
Share
Originally posted by Scott th Ratbag
↑
that works well with trains.... but the boilers here are powering turbines. As I wrote above, there's not a great amount of adjustment able to be achieved with coal-fired steam driven turbines. and this is the key when electricity demand swings are so large as to halve the requirement for production over a 24 hour period.
adding more fuel to the fire should raise the water temperature and hence the pressure of the steam flow to drive the turbines. but this is not a significant amount of change to account for the much larger swings of demand.
What has been happening is the generators take turbines off-line and shut down production from one or more turbines to allow for such swings. and this means further waste of coal as is burned during cool down and more is required to return the turbine to a functioning level.
its not as simple as it looks SG.
Expand
Read up what a pressure relief valve does.
And the furnace temp can be reduced quickly by introduction of water vapour cooling.
Admittedly there is a waste of energy if steam is being vented to atmosphere rather than powering a turbine, but hey, it works and has done for decades and decades.