Somebody linked above to a new closed loop turbine design which uses supercritical CO2. I know from CO2 refrigeration that CO2 has some insane volumetric expansion based on temp which makes it a good candidate for use in a closed loop turbine system. Plus, because they’re running it through the turbine as a supercritical fluid, the density is higher than that of steam so it requires smaller turbines. The biggest issue is that because it’s super critical CO2 youre talking about working pressures well over 1000PSI. That doesn’t make it impossible to work with as we already know from CO2 refrigeration, but it does make it a bit more difficult than just boiling water.
Comment on Gotta go fast
veniasilente@lemmy.dbzer0.com 7 hours agoThat does make sense, but then again, it’s been 2000 years and we can’t find something that boils, expands and compresses better than water? Or is t just because water is commonplace enough in comparisoan?
Canonical_Warlock@lemmy.dbzer0.com 5 hours ago
Teppa@lemmy.world 7 hours ago
I always assume they had additives in closed loop systems, but you’re right you’d think there would be something.
YellowParenti@lemmy.wtf 7 hours ago
Started looking into what liquids they are using and realized i was reading treatment chemicals they add to the boiler water. I know there’s some reactors that use molten salt, but they are just used as energy transfer to… the boiler full of water. Lol. The properties of water expansion from liquid to steam probably can’t be beat or it’s qualities of cheap, simple, good enough.
Test_Tickles@lemmy.world 7 hours ago
I am sure that they have, but there’s a lot more to it than just that. They have to consider long term maintenance, safety, and availability of parts.
Water is known and well established, you can buy a lot of stuff right off the shelf and we know it’s short and long term dangers. Everything else gets expensive and unknown very quickly.