Sandia’s supercritical carbon dioxide (sCO2) Brayton Cycle

The closed Brayton Cycle is a thermodynamic cycle that demonstrates the operation of heat engines, primarily those found in aircraft jet engines and nuclear power plants. Sandia is researching a thermal-to-electric power conversion technology called a supercritical carbon dioxide (sCO2) Brayton Cycle. Unlike the steam-powered Rankine Cycle, the Brayton Cycle uses sCO2 as the working fluid, rather than water, which increases conversion efficiency.

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[rickmorenojr]

For those who are not familiar, the Brayton Cycle can replace the high pressure steam section used in typical steam electric generators. It can be both more efficient and have a smaller footprint compared to the hardware in a steam turbine. It take advantage of the supercritical nature of CO2, which can act like a liquid or a gas.

[StarrDust]

Pls get this working as someone else mentioned it could be also practical for space ships...we're excited about this technology, hopefully we see it in action soon.

[Joe-ijof]

Just tell Congress you need sCO2 turbines for next gen Naval Carriers and Subs because you're worried the Chinese are ramping up work on this too... you'll get all the funding you'll ever need. If ARPA could pull that trick for the Internet, you guys could do it for sCO2.

[iancormie]

Have to admit, I thought this tech was far more mature than it currently appears.

[samuelforsyth]

The optimal power source would be a molten chloride salt fast reactor, temp only limited by vessle material >600c~950. (can go 1100 odd but be nice to the regulators we need them)
For a straight power reactor that pairing is the best currently functional technology we have.
Fusion and SMR seem to have a lot of media support, same conundrum as government, malice or incompetence...

[patrickwalsh]

Would have been nice to get a job at Sandia. Twenty three years working nuclear weapons but no college degree.

[geezzzwdf]

Vrry good glad to see the advantage of good leadership.

[bobthebomb]

Perfect add-on to a small modular reactor.

[Tobiasliese]

What's the issue with "power electronics" exactly? Sounds like a Swiss buck Rectifier would be a decent solution here. 12kw can be done for 300€ @99% efficentcy

[slevinshafel]

i am interesting on this for spaceship. insteaf of nail the preburner and valve and stufs use sCO2 to generate electricity (battery are low energy so combustion for the moment is the way until nuclear is safe to fly) This is small close loop and efficient.
but i need understund better how it work. I mean on water generators convert liquid water in to gas wich increase presure and that presure give mechanic energy. but on crytical fluid how it generate? it will go from superfluid to gas? But you say superfluid have more horse power to move the pale of turbine.
What will move the turbine? if the sCO2 start at 32ºC and 80atm. if i increase temperature the supercriticalfluid will rise the presure? if yes, what is the ratio ºC/atm

[karlswanson]

How about SF6. I know it is a powerful greenhouse gas, so you don't just expel into environment. Maybe the higher density would help with efficiency.

SF6 - Critical temp 318.6K, pressure 3.76MPa, density 736kg/m3.
CO2 - Critical temp 304.1K, pressure 7.38MPa, density 467kg/m3

Could a generator using this technology be used to power a semi?

[paulloveless]

I haven't watched all the way through but is a gas that is in it's supercritical state a fifth state of matter or is a supercritical gas just a property of the gas at certain pressure and temperature parameters?

[calebpoemoceah]

Power and I can clean my laundry without a dryer ? Sweet

[eitkoml]

I want to see how the waste heat gets removed from the system. Since that is supposed to not use water I wonder how big of a radiator is needed for a loop that produces 10 kW of electricity. My guess would be that it would need to dispose of about 12 kW of waste heat.

[personious_k]

no clue what it means, but it sounds good 👌

[calebpoemoceah]

You could wash your laundry too . Maybe a laundry energy mat 🤔.

[WeighedWilson]

My money going to develop a process that industry doesn't want to use, thanks!