A characteristic of any thermal power plant — whether using coal, gas or spicy nuclear rocks — is that they have a closed steam loop with a condenser section in which the post-turbine steam is re-condensed into water. This water is then led back to the steam generator in the plant. There are many ways to cool the steam in the condenser, including directly drawing in cooling water from a nearby body of water. The most common and more efficient way is to use a cooling tower, with a recent video by [Practical Engineering] explaining the physics behind these.
For the demonstration, a miniature natural draft tower is constructed in the garage from sheets of acrylic. This managed to cool 50 °C water down to 20 °C by merely spraying the hot water onto a mesh that maximizes surface area. The resulting counter-flow means that no fan or the like is needed, and the hyperboloid shape of the cooling tower makes it incredibly strong despite having relatively thin walls.
The use of a natural draft tower makes mostly sense in cooler climates, while in hotter climates having a big cooling lake may make more sense. We covered the various ways to cool thermal plants before, including direct intake, spray ponds, cooling towers and water-free cooling solutions, with the latter becoming a feature of new high-temperature fission reactor designs.
Totally unrelated, but it made me revisit my mild obsession with Ranque-Hilsch vortex tubes. I swear their voodoo coolers
It’s like having your own person demon you call Max
There is a campaign to keep at least one of the cooling towers standing at Radcliffe on Soar power station in Nottinghamshire, the UK’s last and now closed coal station for industrial heritage reasons. Nuclear in the UK tends to use marine cooling, and gas sites, forced air, so they are becoming a thing of the past.
When I served in the military, our base generators pumped the hot water to the base heating system. Never understood why communities near power stations didn’t get free heat.
Communities near power stations usually get this heat, sometimes by tens of kilometres of pipes. But in the summer is there still need to cool the process. Which remains me of huge grilles for coolers on petrol / diesel cars, to put one third of the fuel energy to the air. And the designers are proud to pronounce this feature. Off topic point of view.
It’s not that bad. Heat losses to the engine are around 10-20% and the rest goes out the tail pipe.
In modern cars, especially in tiny turbocharged diesel cars, there’s not enough heat to run the air heater in the winter. When you crank up the defroster fan, the engine temp needle in the dashboard starts going down…
Old school method for dealing with an overheating car if you were stuck in a traffic jam.
Turn the cabin heat to full blast (fan included). A failing fan clutch (belt driven) while in stop and go traffic was not uncommon back in the day before electric radiator fans.
Roll your windows down for a bit of personal relief also.
But running the cabin heat full blast still can help with mild overheating, But watch your gauges and shut the engine off if it’s not keeping the temp down below damage range.
Once the thermostat on my Datsun 620 (pickup) stuck closed. The temperature guage maxed out. I drove it for a 100 miles at 55 mph with no damage to the engine!
It was -20 °F at the time, and the cabin heater was not connected through the thermostat, so cabin heater provided sufficient cooling for the engine.
The district heating requires temperatures around 110..130°C, while the cooling towers go down to about 35°C resulting in a much greater electrical efficiency. (The steam from the middle pressure turbine goes either to district heating or to the low pressure turbine.)
Not true. You can heat pump off 20 to 20c with wild efficiency. Lots of district systems without heat pumping operating well below 200c as well
The issue with low temperature district heating is that the water normally starts at 110-130 C from the plant but ends up below 70 C at the end of the route. Then it’s piped back to the plant, with the return loop running under streets and parks to use the residual heat for something. In some versions the leftover water is not returned and just piped to the nearest river at the end, so all of the remaining heat is lost.
If the water starts at 35 C at the plant, it would have to be frozen solid at the end of the pipe to get the heat out for all the customers – or you would have to pump (and heat) a lot more water.
sure, you can pump heat from 20°C, but you lose the same amount of energy (plus losses) to the pump you gain at the last turbine stage (minus losses), so in the end you only increased the losses, defeating the idea
We have a gas cogen plant downtown here that provides district heating to buildings as far as 3km away. It’s miserable — steam leaks all over the place, and the system is under continual maintenance. I can’t imagine the heat is worth the manpower cost.
Yeah, but I’m sure the Greenness feel good about it!
Oh, snark. That’s original.
It is just me or does anyone else want to put this mini cooling tower into a water cooling system in a computer?
cool idea, but keep in mind you add quite a bit humidity to the room air with it
Hmm. In winter my house humidifier dumps several liters of water per day into the air, consuming several hundred watts of heat doing so. This might actually be a reasonable way to cool my wiring closet. I just need to figure how to keep the moist parts away from the computer parts.
Haha, just watched it yesterday. Grady’s great at explaining stuff.
Which reminds me, the local U’s chemistry school has a free drinking water dispenser cooled by an even older school cooling tower made of wood planks, a boon for all the exercising people running in there (half of the old campus was the university, the other had the stadiums and sporting facilities).
An old milk bottling company had one of those too.
I always suspected that another reason for the shape was to prevent resonances with the wind blowing across the top that could make the whole tower fall into a pile of rubble.