
Scientists take strides towards entirely renewable energy - dnetesn
https://phys.org/news/2019-11-scientists-renewable-energy.html
======
black_puppydog
Paper:
[https://www.nature.com/articles/s41467-019-12994-w](https://www.nature.com/articles/s41467-019-12994-w)

~~~
fernly
thanks

------
api
Even better would be to use this to efficiently produce CH4. Now the entire
natural gas power infrastructure becomes a giant battery.

~~~
stefco_
You'd still need to capture/sequester the CO2, which to me sounds much harder
(or else you're only solving the "renewable" part rather than the global
warming part). Water is nice because it naturally precipitates out of the
atmosphere and returns to oceans/lakes/etc.

~~~
api
CO2 + 2H2O + energy -> CH4 + 2O2

Discharging the battery is this reaction in reverse. It's net zero carbon.
It's basically a rechargeable fuel air battery using incredibly abundant
materials so it can scale.

~~~
gus_massa
For comparison, the efficiency of photosynthesis is something like 1%
(probably 2% in C4) but the result is glucose instead of methane. Most organic
reactions have a very low result, I'd be surprised if your reaction has more
than a 10%. Most of the time the molecules have another opinion about how to
combine and they don't produce what you want.

And there is also a problem with the combustion, in a gas turbine you have
only an efficiency up to 65%. So it's a very ineffective battery.

~~~
thaumasiotes
> Most of the time the molecules have another opinion about how to combine and
> they don't produce what you want.

For energy storage, this is, by definition, all of the time. The fact that the
molecules have a different opinion of how they should combine is what gives
potential energy to the form we produce in the first place.

~~~
gus_massa
My handwave chemistry is not strong enough to be sure, but I expect that this
will form also a small amount of ethane (that is not a problem) and also some
soot like goo that will clog the battery and be difficult to burn cleanly
anyway.

------
MeteorMarc
Not an expert in the field but the source below already claims 80% efficiency
in the large scale electrolysis of water, so with little room for improvement.

[https://www.greencarcongress.com/2018/07/20180728-tk.html](https://www.greencarcongress.com/2018/07/20180728-tk.html)

~~~
jeffreyrogers
This research is to find cheaper catalyst for electrolysis. The efficiency is
good with expensive catalysts, but the cost of the catalysts makes scaling up
hard. They want to find cheaper catalysts so that the use of electrolysis to
produce hydrogen can be increased.

------
einpoklum
It seems like they "just" created better tooling for searching for reaction
catalysts, rather than actually found a good new catalyst.

Maybe this is a great stride; but it's difficult to tell from the article
whether that's really the case or whether it's mostly fluff in a grad
student's project. We'll know if/when they actually find something with it.

------
woodandsteel
My understanding is that a key reason cheap electrolysis is important is that
the hydrogen it produces can be substituted for fossil fuels in many
industrial processes, thereby eliminating an important source of co2
emissions.

------
agumonkey
This century will be defined by flipping competition upside down to a race for
efficiency and not power increase.

~~~
mistrial9
They could call this new efficiency savings negawatts ? maybe write a book
about it called "Reinventing Fire" .. could be big

------
fernly
would be nice to have a link to the paper. Anyone?

