Editing Power station (section)

===Cooling towers===
{{main|Cooling tower}}
[[File:RatcliffePowerPlantBlackAndWhite.jpg|thumb|[[Cooling tower]]s showing evaporating water at [[Ratcliffe-on-Soar Power Station]], [[United Kingdom]]]]
[[File:Cooling tower power station Dresden.jpg|thumb|"[[Camouflaged]]" natural draft wet [[cooling tower]]]]

All thermal power plants produce [[waste heat]] energy as a byproduct of the useful electrical energy produced. The amount of waste heat energy equals or exceeds the amount of energy converted into useful electricity{{Clarify|date=October 2021}}. Gas-fired power plants can achieve as much as 65% conversion efficiency, while coal and oil plants achieve around 30–49%. The waste heat produces a temperature rise in the atmosphere, which is small compared to that produced by [[greenhouse-gas]] emissions from the same power plant. Natural draft wet [[cooling tower]]s at many nuclear power plants and large fossil-fuel-fired power plants use large [[hyperboloid structure|hyperboloid]] [[chimney]]-like structures (as seen in the image at the right) that release the waste heat to the ambient atmosphere by the [[evaporation]] of water.

However, the mechanical induced-draft or forced-draft wet cooling towers in many large thermal power plants, nuclear power plants, fossil-fired power plants, [[Oil refinery|petroleum refineries]], [[petrochemical|petrochemical plants]], [[Geothermal power|geothermal]], [[biomass]] and [[trash-to-energy plant|waste-to-energy plants]] use [[Fan (mechanical)|fans]] to provide air movement upward through down coming water and are not hyperboloid chimney-like structures. The induced or forced-draft cooling towers are typically rectangular, box-like structures filled with a material that enhances the mixing of the upflowing air and the down-flowing water.<ref>{{Cite book |editor=J. C. Hensley |url=http://spxcooling.com/en/library/detail/cooling-tower-fundamentals/ |title=Cooling Tower Fundamentals |publisher=SPX Cooling Technologies |year=2006 |edition=2nd |access-date=13 September 2007 |archive-date=18 June 2013 |archive-url=https://web.archive.org/web/20130618074805/http://spxcooling.com/en/library/detail/cooling-tower-fundamentals |url-status=live }}</ref><ref name="Beychok">{{Cite book |last=Beychok, Milton R. |title=[[Aqueous Wastes from Petroleum and Petrochemical Plants]] |publisher=John Wiley and Sons |year=1967 |edition=4th |lccn= 67019834}} (Includes cooling tower material balance for evaporation emissions and blowdown effluents. Available in many university libraries)</ref>

In areas with restricted water use, a dry cooling tower or directly air-cooled radiators may be necessary, since the cost or environmental consequences of obtaining make-up water for evaporative cooling would be prohibitive. These coolers have lower efficiency and higher energy consumption to drive fans, compared to a typical wet, evaporative cooling tower.{{Citation needed|date=July 2021}}