Power sources
I think I short changed you in my last reply ... see what you get?
Anyway, you need to measure or estimate the gozinta vs. the gozouta. What GOES OUT of the battery in terms of power cannot exceed what GOES INTO the battery and vice versa.
For example, on my boat, a single 120 watt Kyocera solar panel (for the most part) will keep up with our electrical consumption so long as the sun is on the panel. Overnight however, we run a deficit of about 50 to 70 amp hours depending on whether or not we watched a PG movie or porn ....
Actually we run the fridge all the time (an Adler Barbour air cooled unit). During the day, no problemo ... after dark, big deficit. So as a result we end up running the main engine (with 65 amp alternator) about 2 hours daily to recharge the house bank batteries. AND yes it takes 2 hours to recover 95% of the deficit.
All of this is monitored on a Xantrex TM500 battery monitor which shows us the battery voltage, amperage currently being drawn (or put in) and cumulative amp hours used (net of contributed) since the last charging cycle was completed. So yes, I know whereof I speak (or type).
All things considered, we should add 240-260 watts of solar panels to our system. That gets a little problematic on an E38. Catamaran, no problem. This is mainly because of suitable mounting locations, size and weight of the panels.
I thought about adding a wind generator; Won't cut it. While lots of cruising boats have them, I've already punished the sailing ability of our Ericson enough, what with bow anchors, roller furling, davits, Mack Pack sailcover, etc. not to mention the weight of various cruising gear. Adding a wind generator just seems like too much crap sticking up there in the already disturbed air.
Besides when you evaluate wind gens, you get numbers like, 'produces 1.5 amps over 24 hours average.' What???, you mean 36 amp hours daily for an investment of over $1000 plus mechanical maintenance and breakdowns??? I don't think so. Plus they're ugly, noisy, dangerous in a blow and belong on power boats... But they run all night.
Still solar panels, with no maintenance should last in excess of 20 years even if they take the nights off and don't need their bearings serviced.
I don't think we have the answer we're looking for yet. Maybe soon though if this green thing keeps researchers working on the problem.
Anyway, I don't know much about the Defender panels. All I'm suggesting is that you need to understand your power needs in total and relate that to available options.
I like solar panels. On the other hand, I did recently see a design for a vertical wind turbine that seems to start up at low wind speeds and can handle very high windspeeds. Plus it is very compact and because it's vertical, doesn't care how it's pointed into the wind; i.e. no tail fin. It's the kind of innovation I like. Smaller, more powerful, simpler, sounds right to me.
Maybe I'm a candidate for the home built wind generator club? Yikes!
