Human warming of Great Lakes
Image NOAA, click for full size.
I came across the above graphic. On pondering I went huh?
The most eastern (right hand) is Lake Ontario. Is that a mistake, the only one largely ice free 2014, largely clear 1994.
I don’t know but I suspected this is the effect of power station cooling water so I started looking.
Following is ballpark back of envelope.
The prayer wheel left hand side given a serious following wind, umm, headwind produces 580ppm of the rest of Pickering nuclear power station and that’s with 1GW of reactors mothballed. Cooling water is Lake Ontario. Roughly, a 3GW station will dump approaching 9GW of heat into cooling.
A station was online 1979 ice, A+B for 1994, reduction 2014.
Website seems to have a tech problem so wiki will have to do
Area whole Lake Ontario 18960 sq/km. I make that 0.47 watt/sqm
Also Darlington nuclear power station cooled by Lake Ontario, 3.5GW, assume maybe another 9GW waste heat.
AES Somerset, 675MW, coal, assume 2GW waste heat.
James A. FitzPatrick, nuclear, 825MW, assume 2GW
Robert E. Ginna, nuclear, 495MW, assume 1.5GW
Nine Mile Point, nuclear, 1757MW, assume 5GW
Oswego, oil, 1700MW, assume 5GW
Is that the lot, I don’t know. Inflow is probably elevated too but this is just idle wondering. I expect someone has done a proper job.
9+9+2+2+1.5+5+5 = 33.5GW = ~1.7Watt/sqm
All will not operate all the time, on the other hand the whole lake will be pumped up slightly, a lot to cool. The station timelines need to be taken into account too.
Evaporation is a very effective cooling system.
Is this a reason for the lack of ice?
Some of the stations have fish farms etc. before the outfall back into the lake. Helps efishency.
Thought I’d better cross check my memory.
“Thermal efficiency %, the ratio of gross MWe to thermal MW. This relates to the difference in temperature between the steam from the reactor and the cooling water. It is often 33-37%.”
Tends to overstate, so ~33% is about right.