[tkwalker]

Folks my two cents worth ... I worked at GSP from 1972 until 1984... As a Senior Instrument Tech, also 212 trips up the stacks for EPA instrumentation(A good view of people catching fish in the canal.) So I know the process very well, unless things have changed with the new EPA scrubbers for emissions. You have four Westinghouse steam turbines two of them are 312 mega watts and if I remember correctly the other two are 275 mega watts ... The boilers were Babcox Wilcox.

Unless the the turbines have been up graded to German units? Even so the process is the same. What heats the discharge canal is the condensate that the temp is from the low and final stage of the three temp cycles that enters the three stages of blades of the turbines .. Rotating and stationary ... IT IS A TURBINE..The condensate from the tubing sweats from the warmer than ambient air .. This has nothing to do with the steam cycle of the boiler which reaches super heated steam of 1050 degrees at above 1000 psi. ... This is condensate, similar to what your Home heat pump does when it goes through a defrost cycle,that's the water you see around your unit, or the water dripping from your unit in the summer .. AT GSP the Condensate,(sweat) from the tubes of the spent steam is what creates the actual water discharge in to the canal... The steam is a captured system under a lot of pressure and heat. The boilers pretty much don't change as far as temp... The amount of steam is always there ... The spent steam reenters the boiler from the turbine .. There are three stages, High,Intermediate, and low to be reheated...

The lose of a minute canal temp is common in the spring and Fall when turbines are taken off of the line for either boiler or Turbine outages (overhauls) but rare in the winter unless an emergency of a downed unit ... but even at that any of the units running will develop a higher temp than river temp ...

Now it has been 34 years and I am 73, I may have not remembered every detail and may have some things screwed up ... But I hope this clears up some of your questions .. The only way the discharge canal can be the same temp as the river ... There are no units running ... I saw this once the in the 13 years I was there <'TK><

Note: In the winter when you see a white discharge coming from the stacks, this is condensate caused by the warm discharge gases meeting the cold air temps... similar to your automobile when you first start it up in the cold mornings .. But if you see a black smoke coming from the stacks this could be from starting up a unit.. shutting down a unit or problems like the boilers going on pressure (these a negative pressure boilers) electrostatic precipitaters problems etc ...