"A...solar battery?"  The look on Carrie's face says clearly that this sounds like utter nonsense.  "All the fridges I've ever seen used a steam-powered exothermic resonator to chill the interior.  Solar power was proven to be a total dead end almost a century ago."  She shakes her head.  "Okay, I'm definitely asking the wrong questions.  What planet are we on?  This<em>looks</em>like Earth, but it can't be."