31–40 of 106 posts
I wonder why they used tap water instead of seawater
Why they should use seawater? Fresh water is not in shortage in this region - yearly precipitation significantly exceeds evaporation.
One application of this technology is to economically harnessing fusion power. Sadly there are considerable engineering and political difficulties. https://en.wikipedia.org/wiki/Project_PACER
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They have a massive desalination and pipeline operation to create lakes throughout the country? Or is it the the sun and rain that created the lakes?
https://www.geographyrealm.com/finland-many-lakes/ Thanks to the last ice age and retreating glaciers...
The fact that they are still full of water is due to them being replenished by precipitation more than they lose water. If they would lose more water then what flows into them we would be speaking about the "land of many bone dry holes" in the famous Finnish desert.
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That's what I would normally have assumed, but 100C seemed a little hot for water just sitting in a big cistern
I'm no physicist but I assume that you'd need to put a lot more energy into the system before the water starts boiling, so you wouldn't have to worry about it? If the energy would just be lost otherwise, you might as well go all the way to 100℃? That's at 1 atm, perhaps the water is a bit pressurized as well? A bit further down there's this confusing quote though: > District heat is stored in two rock caverns in Must…
This energy storage system near Helsinki, Finland operated by Helen ( https://en.wikipedia.org/wiki/Helen_Oy ) might be interesting for HN readers. Some facts from previous article ( https://www.helen.fi/en/news/2020/mustikkamaa ), not sure which one would've been better in url field: District heat is stored in two rock caverns in Mustikkamaa. The temperature of the water in the caverns varies between 50 and 90 °C. T…
Earlier quoted context omitted.
That's what I would normally have assumed, but 100C seemed a little hot for water just sitting in a big cistern
I'm no physicist but I assume that you'd need to put a lot more energy into the system before the water starts boiling, so you wouldn't have to worry about it? If the energy would just be lost otherwise, you might as well go all the way to 100℃? That's at 1 atm, perhaps the water is a bit pressurized as well? A bit further down there's this confusing quote though: > District heat is stored in two rock caverns in Must…
I suppose in such a large storage vessel, most of the water is naturally pressurised by its own weight. So most of it won't boil, even at 100°C, except right at the surface?