I wouldnt be with out it now. most of the places I go to with the truck camper have no services. I did change all my interior lights to LEDs, but not with the energy savings as the primary concern but rather for increased brightness and ya a bit for the power savings. I do not have a low power consumption when i go out in the spring and fall. I have the furnace running, lights radio and so on and by noon my GC2 batteries are full again. I have camped in shade and still charged well. the right pannels make a huge difference, ie. go for 24V split cell panels.
as for cost, I think to many people are stuck at pricing that was 5 to 10 years ago. it cost me 600 cdn to put my system on my camper, so even the difference between booking serviced to unserviced sites (50-65 to 18-25) thats less than 20 nights of camping to pay for its self, if I am boondocking then I can pay for its self in about 10 nights.
I started out with a single 325 watt panel to test it out and will be increasing it to a second one and going to LiFePo4 batteries for more capacity. right now I can go 3 days with out sun before I start to get concerned, in the fall using the furnace at night. I want to get that up to 7 days min.
I have 450 watts on my 5th wheel and I dont worry about what I paid for that either as normaly we are looking for services when we take that as its to big for a lot of forestry sites, but for the times when we do take it where there are no services it is priceless, the solar lets me run my margaretavill, bar fridge and icemaker for a few hours a day, which can lead to some pretty good times in the middle of nowhere. this two is in the plan to upgrade the panels to around 1200 watts and go to about 800ah of Li batteries.
Steve
Steve