cooling tower 
noun
A tall, open-topped, cylindrical concrete tower, used for cooling water or condensing steam from an industrial process.These turbines are taller than the cooling towers at Drax Power Station and almost twice the height of York Minster....
- Experts are examining water systems, particularly those where warm, stagnant water is found such as hot water tanks, cooling towers, whirlpool spas and air conditioning and plumbing systems.
- In the shadow of four concrete cooling towers - almost 400 feet each - this squat earth-tone building sits shuttered.