As a former editor of Astrophysical Journal he must be regarded as a serious scientist within his field.
The JBIS is not on the same level as Nature or Science but it is a peer-reviewed journal. They do allow more speculative articles to be published.
Hairsch's work on zero-point energy is speculative but the phenomenon of zero-point energy does exist in quantum physics. The only question is how to exploit it.
I would say the status of zero-point energy now is about the same as that of atomic energy in 1930:

"There is not the slightest indication that nuclear energy will ever be obtainable. It would mean that the atom would have to be shattered at will."
- Albert Einstein, 1932

"The energy produced by the breaking down of the atom is a very poor kind of thing. Anyone who expects a source of power from the transformation of these atoms is talking moonshine."
- Ernest Rutherford, from speech given at the British Association in 1933.

Atomic fission was finally achieved by Hahn and Strassman in 1938.

Bob Clark