It is very clever; you can have it shut off or on at times you program in as well, so you don't have to leave it on all night. You can adjust it for "political or economic boundaries" to time zones. But not clever enough; it doesn't reset for daylight saving time. And why is longitude relevant? And could a photo cell not figure out when it was getting dark just as easily?
Unlike Jaymi's Vent-Miser, it doesn't need batteries, but charges its own internal batteries off the mains, so there will be a little bit of phantom draw.
Like the vent-miser, one has to wonder why we can't just make our houses smarter and handle these things centrally. Or just convince the Mother-in-Law that she really doesn't need to have a light on when she is not in the room.
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