# Baseload Generators: Relationship between output and cooling water

Hi,
I'm just wondering if anyone is aware of any formulas that could describe the relationship between the cooling water and the output of a
power plant (baseload such as coal-fired generator)?
I understand that during periods where the cooling water is rationed (due to drought, etc), power plants will have to reduce their output, but I'm not sure how much they would have to reduce, etc. There's also a relationship between the temperature of the cooling water and the output.
Any ideas would be welcome. Thanks.
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In alt.engineering.electrical snipped-for-privacy@hotmail.com wrote:
| I'm just wondering if anyone is aware of any formulas that could | describe the relationship between the cooling water and the output of a | power plant (baseload such as coal-fired generator)? | | I understand that during periods where the cooling water is rationed | (due to drought, etc), power plants will have to reduce their output, | but I'm not sure how much they would have to reduce, etc. There's also | a relationship between the temperature of the cooling water and the | output.
It would be reduced to the point where the available or decided water flow rate can still keep the generator running at the specified frequency. The water flow would generally be a function of the generated power. There may be reasons to avoid using the hydro power at that time to keep it in reserve, or to keep the water in reserve. These are complex and often political decisions. Other natural energy sources such as wind power do not face those kinds of decisions, though clearly they do face variations in how much power is available.
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| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
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efficiency rejects about 1.137e6 BTU/second. In a cooling tower, that's evaporating water at about 1034 lbm/second. That's about 7450 gallons every minute *before* considering drift or 'blowdown'. That same plant may actually need between 10,000 and 12,000 gallons every minute to operate at full power.
If it's an 'open loop' plant using a river/lake directly, with a 30F delta-T limit on their discharge permit, that 1.137e6 BTU/second being rejected to the cooling water would require cooling water flow rates of about 275,000 gallons/minute.
As you can see, thermal power plants are 'thirsty' creatures.
daestrom