[ultramundane828]

I have a possibly slightly tangential question for the community:

Any solar experts willing to weigh in on the author's assessment of the current state of solar?

Specifically, were a sodium ion battery commercially available (with similar efficiency to lithium ion batteries) tomorrow, would we be living in the golden age of solar energy?

This is something I'm extremely interested in as a citizen of planet Earth.

[mrinterweb]

I've never understood why hydrogen is not considered as an energy storage medium. Energy produced by solar panels could be used to create hydrogen, via electrolysis, that would later be burned to create energy at night. I guess the risk is that hydrogen is very explosive and maybe it is too difficult to mitigate that risk.

Update: I did find that people are using hydrogen as an energy store. http://schatzlab.org/projects/archive/schatz_solar.html

[EdwardMSmith]

It's a storage issue. Storing a useful quantity of hydrogen is very difficult.

[curtis]

Storage is certainly difficult, but there's also a fairly serious efficiency loss as well.

[cinquemb]

Solar is pretty interesting because people (the media) seem mostly fixated on panels where the current potential at bridging the energy gap as far as acquiring and distribution is concerned, seems to be CSP technology.

The storage medium for CSP is typically some kind of molten salt mixture (NaNO3, KNO3, Ca(NO3)2) which is then used on a closed circuit of water to power steam turbines. Right now this is limited to large facilities. In practice, CSP can be done on a small modular scale.

Here's an example of CSP at a large scale in Spain: https://www.youtube.com/watch?v=LMWIgwvbrcM There are also other places in world where facilities like these exist.

Here's an example of CSP at a smaller scale: https://www.youtube.com/watch?v=-SsJBobMpAk However, they use glycol (smaller thermal capacity) as a heat transfer medium instead of molten salt.

As for batteries for devices, that wouldn't necessarily equate to a golden age of solar energy because there is still larger issue of how the energy will get to the device and at what cost.

[ultramundane828]

Thanks for the response! I had known about CSP but didn't think about it in this context, which is a major neglect on my part.