I mean, you can be environmentally conscious and
also not want to be fucking miserable (e.g. leaving it at 80F -- I've been there, done that, in similar conditions to that kind of texas heat, and it can
easily leave a person a non-functioning waste of a human being if they're stuck in it for an extended period)? Basically means you'd be focusing on some other part of your behavior, or making sure to have as energy/etc. efficient an aircon as you can manage, or maybe going easier on the thing during the parts of the year that
aren't "fuck you long pork, boil standing up", or donating/etc. for environmentalist projects, or a pile of other things.
It'd be problematic if they claim to be that and aren't aware of the discrepancy and trying to make up for it, but without that sort of context it's not an invalidating thing in and of itself, y'know? There's not any one thing that's necessary to call yourself concerned for the environment, just a pile of sufficient ones that can vary in adherence from person to person and situation to situation.
E: Though the strained power grid in tex isn't due to the heat, it's due to the fuckwits in charge of the infrastructure in that state not preparing for the entirely predictable heat in question. Capitalist profit fetish, probably going to kill more people this year