Cooling systems in thermal power stations

[Gruxg]

I thought any type of thermal power sation required a powerful cooling system and therefore had to be located near a large water mass (river, sea) or have big cooling towers: I have seen this in nuclear, gas or biomass stations. However, I haven't seen it in concentrated solar power stations despite they use steam turbines like any other termal station (if I am not mistaken). Once the heat is produced by any means, I suppose the thermodynamics should not be very different: why (thermal) solar stations do not need such big cooling towers nor large water supply like the other stations?

 

[jedishrfu]

Interesting question, I found these references that may answer it:

https://www.energy.gov/eere/solar/articles/novel-dry-cooling-technology-power-plants

https://www.azocleantech.com/news.aspx?newsID=31739

 

[gmax137]

Normally, steam engine power plants utilize the water-intensive wet cooling technique to disperse the waste heat that has been generated. But such processes have the ability to lose huge amounts of water as a result of the evaporation and, thus demand a constant water supply.

This poses a severe threat as the majority of the CSP plants are set up in hot and dry regions with restricted water resources.

I don't think I say "severe threat," rather, "design constraint."

 

[Rive]

I thought any type of thermal power sation required a powerful cooling system and therefore had to be located near a large water mass (river, sea) or have big cooling towers:

You are right, they do need cooling the same way as any other thermal power station.

why (thermal) solar stations do not need such big cooling towers

As far as I know there are multiple reasons.
- since there is usually no water nearby at all, they prefer dry towers with forced ventilation. And those are lot smaller.
- usually these CSP stations are at lower capacity than those big power plants => less cooling is needed.
- the sheer size of the plant is lot bigger, and cooling is just harder to notice.
- also, those iconic natural draft towers are associated with 'bad power', so if it's just matter of choice then it'll be something else.

'Bookport CSP plant' is 50MW and all the cooling it needs is that three shaft white-ish block with the green piping on the right side of the block of machinery. The perspective is tricky that thing is still big from up close.

You can find some more here, for example.

 

[russ_watters]

Dry coolers are fine, they just have lower performance/efficiency than evaporative coolers if you have water available and have a choice. Evaporative towers approach the wet bulb temperature whereas dry towers approach the dry bulb. For my area that means a wet tower provides 85F condenser water on a on 98F day (78F wet bulb) vs 105F condenser water for a dry cooler.

Other considerations:
-Wet towers are air cleaners. All the dirt/dust in the air flowing through the tower ends up in the water.
-For cold water/ambient operation, you may need anti-freeze and that dictates a dry tower.
-Legionella. Not a concern in a dry cooler.