
Storing Renewable Energy Using Thermodynamics - martind81
http://www.airthium.com
======
Nomentatus
Similar tech, I expect:

[https://arstechnica.com/information-
technology/2017/04/start...](https://arstechnica.com/information-
technology/2017/04/startup-says-it-can-make-compressed-air-energy-storage-
scheme-dirt-cheap/)

[https://www.thenational.ae/uae/compressed-air-the-battery-
of...](https://www.thenational.ae/uae/compressed-air-the-battery-of-the-
future-1.338460)

[https://www.engadget.com/2013/09/16/sustainx-turns-on-
first-...](https://www.engadget.com/2013/09/16/sustainx-turns-on-first-modern-
megawatt-scale-air-battery/)

------
IndrekR
Assuming about 300K ambient temperature (on site, above ground), 800K working
temperature (store the heat at 500°C) and that the second law of
thermodynamics still holds, the roundtrip efficiency can not be 70%. It must
be below 40%, and not just a bit below.

~~~
petermcneeley
I think you might be wrong but my thermal is very rusty. Where you are wrong
is that you might be forgetting the over 100% efficiency in heat transfer when
using a heat pump.

[http://energystorage.org/energy-
storage/technologies/pumped-...](http://energystorage.org/energy-
storage/technologies/pumped-heat-electrical-storage-phes)

[https://www.economist.com/news/technology-
quarterly/21603184...](https://www.economist.com/news/technology-
quarterly/21603184-reversible-heat-pump-promises-cheap-way-store-renewable-
energy)

[http://wordpress.ei.columbia.edu/lenfest/files/2012/11/Abstr...](http://wordpress.ei.columbia.edu/lenfest/files/2012/11/Abstract-
Nearly-Reversible-Heat-Engines-for-Thermal-Storage-of-Excess-Electric-
Power.pdf)

~~~
IndrekR
You are right, I stand corrected. If instead of the ambient temperature, we
have a cryogenic storage tank, getting 60% round-trip may be feasible in large
scale.

------
smartmic
I am missing a profound description of the technology. Where is the
innovation? The website containing only some key words is too sparse to arouse
serious interest.

~~~
quantum_state
Same observation here ... seems to be a bit nebulous ...

------
luhn
They claim 0.05€ (~0.06USD) per KWh lifetime cost. Anybody know how that
compares to current prices of grid-scale batteries? I can't find a up-to-date
source.

~~~
aidenn0
Pumped hydro is about 3x as expensive, and batteries I think are still more
expensive than pumped hydro, so it's absurdly cheap.

~~~
petre
Pumped hydro and flywheels are at least demonstrated cost effective solutions.
This? They don't even provide any details.

------
Asturaz
The issue with storing energy is that en investment of building infrastructure
to transport the energy where it is deficit of energy is a more market safe
solution.

------
thinkcontext
Interesting concept. Wake me up when they demonstrate 10MWh.

------
hprotagonist
forgive me if this is totally petty, but: "thermodynamic" is an adjective, not
a noun.

"Storing Renewable Energy Using Thermodynamic" ... what, exactly?

~~~
craig1f
First, not saying I believe that these guys are legit, but "thermodynamics" is
a noun. Thermodynamic energy is a type of energy, like chemical energy is a
type of energy. There is also nuclear, stored, potential, light, kinetic, and
I'm sure I'm missing a few.

These are all basic physics concepts. These guys are claiming to be able to
store the energy as thermal energy, and then get it back out at 70% efficiency
without much degradation inside of 25 years.

All these ideas are plausible from a physics point of view, but I don't buy
this simply because it requires an efficient way of converting heat to energy.
If this existed, it would already be a holy grail for other reasons. Being
able to turn the waste-heat from an engine back into more energy efficiently
would be incredible. Right now, to get energy from heat, you typically need
the heated material to be near something that's very cold, and you use the
difference in temperature to get energy out of it. Or you boil water and spin
turbines. It sounds like MAYBE that's what these guys are doing, if what they
are claiming to be able to do is legitimate.

~~~
hprotagonist
thermodynamics, yes.

"thermodynamic" is an adjective that denotes "having to do with
thermodynamics".

this is utterly petty, i know, but it really jars.

