Eli5: Why are nuclear power plants smoke stacks shaped so differently from others?

Question

If it’s just for steam why make it different?

In: 13

Answer 1

The wide hourglass-shaped towers you’re thinking of are not smokestacks, and are not unique to nuclear power plants. They are cooling towers. Every power plant needs to dump heat into the environment. Cooling towers work by spraying mist over pipes carrying hot water; the mist cools the pipes and evaporates into water vapor that rises up the tower. The hourglass shape of the tower increases the speed of the rising air, making cooling more efficient.

There are other ways to cool a power plant, though: one of the most common is to run river or seawater over the hot pipes instead. Both nuclear and fossil fuel power plants can use this method, but it only works if you’ve got a good supply of water.

Here are some nuclear power plants that don’t have cooling towers, because they use river or ocean water to cool off:

[https://www.epa.gov/npdes-permits/pilgrim-nuclear-power-station](https://www.epa.gov/npdes-permits/pilgrim-nuclear-power-station)

[https://en.wikipedia.org/wiki/Diablo_Canyon_Power_Plant](https://en.wikipedia.org/wiki/Diablo_Canyon_Power_Plant)

[https://en.wikipedia.org/wiki/Indian_Point_Energy_Center](https://en.wikipedia.org/wiki/Indian_Point_Energy_Center)

Here’s a coal power plant that does have cooling towers, because the local community complained that the hot water it was dumping into the harbor was killing fish. So they built huge cooling towers at enormous expense, and then coal power became unprofitable so they demolished the whole thing including the brand-new towers.

[https://www.powermag.com/new-englands-largest-coal-and-oil-power-plant-to-close/](https://www.powermag.com/new-englands-largest-coal-and-oil-power-plant-to-close/)