In the last 2 weeks we have been on two 4 day camping trips to the mountains of Colorado. These were the first trips after adding a unisolar 136 watt panel which is 18' x 15" and is self adhesive on the roof along with a morningstar mppt controller. About $400 with the wiring and dicor. Both trips we used the batteries to charge laptops and the battery for the sawzall along with the lights for four people with two small kids. I haven's switched over to led's yet and have a 5 year old group 31 and a 2 year old smaller walmart battery. The batteries were always charged by early afternoon even being in the trees and overcast a good portion of the time. The second trip we were so confident we didn't bring the generator.