For me, the bigger panels I need for my 24V system would cost around the one thousand odd pounds mark (US$ 1,600), so some research makes sense.
The concept seems idyllic - slap in a couple of solar panels and job done. Free power for the next twenty odd years with no maintenance other than an occasional clean of the panels.
After looking into it a little more, I must say that I'm somewhat under whelmed by the whole idea.
Green issues aside, solar power looks very expensive for pretty poor returns.
The panel you see is one of two different types I bought for my solar power experiments. This one for my on-board 12V system.
Forty quid that cost me, and it only produced a sorry amount of power over the course of the last few weeks. Not even enough to keep up with my intermittent use of the radio. Oh yes, and the battery is in really good shape as it's quite new.
4.8w output I think is promised on the box, but in reality I think it only does that when it's pointed directly into blazing sunlight. That's not going to happen. Especially here in England in the daylight savings months.
Before we go any further, bear in mind that this panel could not keep up, so I'd have to use a generator to top up the power at some point anyway.
So here's my, very rough, calculations....
Forty quid buys me forty litres of petrol. At .4 litres per hour (1/4 load from here), this gives me 100 hrs (6000 minutes) generator runtime. In reality the generator will use less petrol than that, as the load to charge the 12V battery is not that significant (say 10 amps * 12V = 120W vs 500W for 1/4 load).
I estimate it would take a maximum of 5 minutes generator runtime to produce the same amount of charge that panel did in two weeks.
Based on the above, 2.5 minutes runtime per week, that forty quid on the solar panel buys me the equivalent of (6000/2.5) 2,400 weeks, or 46 years, generator charge time.
End of experiment.