Casio has a line of solar powered watches that seem to do well enough on normal room lighting, speaking on the basis of five years of avoiding the sun and not seeing the battery dip below the highest indicated charge.
I also find it convenient that they are water resistant to 100m, and relatively inexpensive (about $60, half that on sale).
They aren't officially dive rated, but I they make a good backup to a dive computer and so far I have never had one fail. If it does, replacement is cheap.
Just check it for any sign of leakage or condensation before a dive... and never, ever wear it in the shower, bath, or while doing anything else involving detergents or anything else other than some kind of (possibly salt) water, or chlorine or bromine in swimming pool concentrations.
Biting the hand that feeds IT
