5 ms·

Your comment fascinates me. A normal ice hockey rink is 1,800 square meters. The biggest indoor ice rink in the US is the Schwan Super Rink = 28,000 sqm which c

Your comment fascinates me. A normal ice hockey rink is 1,800 square meters. The biggest indoor ice rink in the US is the Schwan Super Rink = 28,000 sqm which consists of 8 separate rinks. Yuma's 4 runways total 543,000 sqm. At midday those runways are absorbing 543MW of energy from the Sun. So that might require 100-200KW of electricity to run the heat pumps. And then you still need somewhere to dump the heat. In short, I think the reason they don't cool runways is due to the cost.

yetanotherloser 4y ago
Then we wonder why when it's hot, it's really bloody hot at airports. Is that sum really right? that an airportsworth of tarmac is like a whole power station pumping its entire output into ground heat? because it looks right to me and it seems like the easy, sensible option is just to rip up the airport...
johnwalkr 4y ago
There's a ton of comments on HN like this. A quick brainstormed "why don't they just.." as if cooling a runway, building a subway, conducting space travel or doing anything else bound by physics is as trivial just because it is conceptually simple. Might as well ask why you can't ski in your backyard in London because after all it is trivial to add some pipes to your refrigerator. Also I don't know of any skating rinks that operate outdoors in summer, or to use a more favourable example, something like lowering a surface temperature from 20C to -5C (an ice rink, indoors) vs lowering a surface temperature from 80C to 55C (an assumption for a runway, outdoors). Even Dubai, a major transport hub, much hotter than UK even this week, with cheapish energy costs, little public debate uses other mitigations such as runway materials and scheduling many takeoffs for 2-5AM (there are many costs due to high temperature besides runway degradation).
legostormtroopr 4y ago
Isn't a large part of electricity production around making things hot to drive turbines? Airplanes are very heavy so this may not be physically possible, but if you could run coolant pipes under runways, couldn't that captured heat be used in energy production elsewhere?
- badcppdev 4y ago
  Yes. You could heat fluid and use it to generate electricity as you can assume the runway is hotter than the ambient air. But if you look at other solar thermal power stations [0] you can see that they generally use concentrators to get the working fluid very hot for more efficient operation. So a runway based system probably wouldn't be economical even if it were good reuse of space. 0 - https://en.wikipedia.org/wiki/List_of_solar_thermal_power_stations https://en.wikipedia.org/wiki/List_of_solar_thermal_power_st...

yetanotherloser 4y ago

Then we wonder why when it's hot, it's really bloody hot at airports. Is that sum really right? that an airportsworth of tarmac is like a whole power station pumping its entire output into ground heat? because it looks right to me and it seems like the easy, sensible option is just to rip up the airport...

johnwalkr 4y ago

There's a ton of comments on HN like this. A quick brainstormed "why don't they just.." as if cooling a runway, building a subway, conducting space travel or doing anything else bound by physics is as trivial just because it is conceptually simple. Might as well ask why you can't ski in your backyard in London because after all it is trivial to add some pipes to your refrigerator. Also I don't know of any skating rinks that operate outdoors in summer, or to use a more favourable example, something like lowering a surface temperature from 20C to -5C (an ice rink, indoors) vs lowering a surface temperature from 80C to 55C (an assumption for a runway, outdoors). Even Dubai, a major transport hub, much hotter than UK even this week, with cheapish energy costs, little public debate uses other mitigations such as runway materials and scheduling many takeoffs for 2-5AM (there are many costs due to high temperature besides runway degradation).

legostormtroopr 4y ago

Isn't a large part of electricity production around making things hot to drive turbines? Airplanes are very heavy so this may not be physically possible, but if you could run coolant pipes under runways, couldn't that captured heat be used in energy production elsewhere?

badcppdev 4y ago
Yes. You could heat fluid and use it to generate electricity as you can assume the runway is hotter than the ambient air. But if you look at other solar thermal power stations [0] you can see that they generally use concentrators to get the working fluid very hot for more efficient operation. So a runway based system probably wouldn't be economical even if it were good reuse of space. 0 - https://en.wikipedia.org/wiki/List_of_solar_thermal_power_stations https://en.wikipedia.org/wiki/List_of_solar_thermal_power_st...