Hi all, I'm currently building my first model - a loyal class from Model Slipway, and would like to power up 30 x 6 volt grain of wheat bulbs all at the same time (

) I have fitted one to every lamp possible including 4 in the wheelhouse. I know there are correct lighting sequences for varying conditions etc. but it's my first dabble and am having fun, they won't be a true representation in real terms, but they might look pretty!

I'd like to use a "boxy" shape sealed lead acid battery dedicated to the lights and help towards ballast.
Can anyone recommend the size of battery (power / amp hrs) needed for a number of 10-15 minute durations without having to constantly recharge, and also how much juice the lights will pull.
I've heard these bulbs don't last too long before burning out, but I'm too far down this road to change now.
Cheers, Tony.