Great! That doesn't sound expensive, well done. I have a car battery and invertor, just in case, for backup if something goes wrong it gives us a day of working on our PCs... if I don't use the coffee machine, of course :)
The only downside I hear are the limited recharging cycles, compared to the Lithium batteries but their price is another story.
I bet sometimes weird stuff happens on those boats so I guess there are real cameras as well! :D