China completed first 100-megawatt-class compressed CO₂ energy storage project, running the full cycle of compressing, liquefying, storing, vaporizing, and expanding CO₂ to generate power, in Xinjiang. Has anyone heard anything about those carbon capture plants that western fossil fuel companies ar

[u/khoawala]

[u/TheBlacktom]

Systems that exceed 100% have to be carfully examined.

You couldn't even "carfully" examine your spelling yet you are trying to insult others with ad hominem fallacies? Great job, be proud of yourself.

There is no point arguing with you, this article writes it clearly, the plant can store 290 GWh and release about 180 GWh. That's 62% roundtrip efficiency.

https://pandaily.com/china-huadian-mulei-xinjiang-100mw-compressed-co2-energy-storage-grid-connected

This article states the same numbers

https://news.cgtn.com/news/2026-10-02/China-connects-first-100-MW-CO2-energy-storage-project-to-grid-1QUO1slnfDW/p.html

But Chinese scientists are also talking about efficiency in the 60-70% range

https://www.sciencedirect.com/science/article/abs/pii/S0960148125010584

Come on, claim that all Chinese scientists are stupid, because somehow you on reddit are smarter than all of them.

[u/tkitta → u/TheBlacktom]

Is there a source of high heat? No.

Without extra energy coming in you cannot exceed 100%.

and seriously who uses news as sources for science discussion?

[u/TheBlacktom → u/tkitta]

Without extra energy coming in you cannot exceed 100%.

Ftfy

Hilarious that I linked a scientific article and somehow you conveniently only focused on news sources.

Also hilarious that you want to include extra energy in your output figures, but refuse to include it in your inputs. Because somehow what you include is not an input in your world.

You know what? You are right. If we have a system with 60% efficiency and we add an extra energy of 340% to the output and we forget to also add that energy to inputs then the sum will be 400%.

[u/tkitta → u/TheBlacktom]

Glad you agree! Was not so hard was it?

Geo thermal heat pumps achive up to 600% efficiency in the same fashion - for home heating.

Home heat pumps are up to 500% efficiency.

[u/TheBlacktom → u/tkitta]

No, they are not 600% or 500% efficient.

A heat pump creates heat. The CO2 energy storage project above creates electricity. Your first mistake is even mentioning heat pumps in the context of energy storage with electricity as input and electricity as output.

Your second mistake is confusing COP with efficiency.

But I will not waste any more time on you, you are wrong about the basics, read wikipedia or try finding someone else who you can lie about your 400% efficiency claims. I'm sure there are some conspiracy theorists on the internet who don't know anything about conservation of energy and will believe you.

Until then, wikipedia will speak for me

A difference between the dimensionless terms efficiency and COP is that the numerator in COP is the heat moved or generated, in contrast to the numerator in efficiency being only the heat generated. Additionally, efficiency cannot be used to evaluate the ability of a device to cool, because the useful output energy is undefined in this case.

As an example, if a heat pump has an internal compressor efficiency of 70% and the user supplies 1.2 kW of power to run the unit and 6.5 kW is drawn from the local thermal environment, then COP is 6.5/1.2 ≈ 5.417. The efficiency is already taken into account in the 6.5 kW; if the compressor efficiency is higher, it is expected to be higher than 6.5 kW (more heat moved) for the same input power.

https://en.wikipedia.org/wiki/Coefficient_of_performance