The scientific literature has almost entirely ignored this theory
The episode (9:54) doesn't present the battery theory as conclusive fact.
It is just a theory. They still need to work out how the theory could cause the lights to hang in the air. But for the time being, its the best theory they've got.
There are two facets of this that can be checked:
- Is this a real theory that real scientists take seriously? Not really. It has never been published in a scientific journal. The scientific literature has almost entirely ignored it.
- Is there a more widely accepted theory? Two other scientists, Paiva and Taft, have done work that has gotten more acceptance than this theory. Their work does not appear to have gotten widespread attention or acceptance.
Is this a real theory real scientists take seriously?
This perspective letter published in a scientific journal reviews 3 explanations for the phenomenon. The third explanation matches the one given in the episode. A perspective letter is more like an opinion piece than a in depth scientific investigation. They typically go through an abbreviated peer review.
Physicists have suggested few models to account for the HL phenomena. One possible explanation attributes the phenomena to an incompletely understood combustion process in the air involving clouds of dust from the valley floor containing scandium (Hauge, 2007, 2010). Another hypothesis suggests that HL are formed by a cluster of macroscopic Coulomb crystals in a dusty plasma produced by the ionization of air and dust by alpha particles during radon decay in the atmosphere (Paiva and Taft, 2010). The valley's shape, microclimate or unique geology might also act as a giant battery that powers the lights (Monari, 2013). Until recently, none of the hypothesis/models described above seems to account for all the observations of HL and the very high energy source generating HL remains completely unknown.
The Monar 2013 report presents the giant battery hypothesis, and presents some data that is consistent with the hypothesis. This data is far from conclusive and the report makes clear that this is just a hypothesis. It was not published in a scientific journal and I have no evidence that it went through peer review. It has gotten almost no scientific attention; According to google scholar, the perspective letter quoted earlier is the only scientific source that cites this report.
I do not see any evidence that this theory is taken seriously by the wider scientific community.
Is it "the best theory they've got"?
The perspective paper mentioned two other theories. Hauge proposed that burning scandium causes the lights. Paiva and Taft proposed that it is caused by a dusty plasma.
Hauge 2007, is a "preliminary report" that does not appear to be published in a scientific journal. It presents a little bit of evidence that supports the possibility that burning scandium dust is causing the lights. Although it has been cited by 8 other papers, none of them give it more than a cursory mention. Hauge 2010, was published in a peer reviewed journal and has been cited by two articles other than the perspective letter. I don't take either article seriously. One is short, doesn't really explain its methods or data, and is published in a probably predatory journal. The other explains that an alien "exo-civilization" built a "stealth extraterrestrial visitation probe" that is causing the lights.
Paiva and Taft are two scientists who have published extensively about the Hessdalen lights. They have proposed several physical models for how the lights occur (2010,2012,2011,2012,2011). These models discuss dusty plasma, and charged particles emitted from rocks that fracture as they thaw. Most of them are published in peer reviewed scientific journals. Most of them have gotten at least 1 citation. The scientific community appears to take Paiva and Taft far more seriously than Monar or Hauge.
This could be because their theory correctly explains the evidence, or it could be because they know how to write papers that will get accepted, or both. Although their work has more acceptance than the other two theories, that is a pretty low bar.
Speculation about the show
I personally have a good scientific background; for most scientific papers I can understand a decent amount of what is being discussed. Paiva and Taft's papers go right over my head. If the people creating the show looked at their work, they probably decided it was too complicated and arcane to try to explain to their viewers.