This year will be my first burn and unfortunately I am a bit of a noob when it comes to electronics, and so I was hoping I could borrow some of your wisdom

My team and I will be building a small pavilion and in order to light the piece at night I have proposed 20 x 12W LED light bulbs (12V) at various locations which will be powered by deep cycle batteries.
Assuming these are lit up for 8 hours a night, doing simple calculations I've worked out that a night would require 160Ah.
12W @ 12V = 1Ah
20 x 1Ah x 8 hours = 160Ah
Therefore I've decided to go for 2 x 90Ah Deep Cycled batteries in series to obtain 12V 180Ah.
http://www.batterystuff.com/batteries/u ... 45826.html
These batteries will be recharged everyday during the day, and I've gone for a 12V 20A charger which will likely take 10 hours to charge the batteries (not sure if more would be a good idea, as I've been told it may just end up being "surface charged").
http://www.batterystuff.com/battery-cha ... -1120.html
I hope I am on track so far but this is where I'm a bit lost as I'm not quite sure how to work out what generator is best suitable for this setup...
If the generator charges the batteries at 20A at 12V for 10 hours (2400W), I should look for a generator that can output 2400W + power?
