Tricksailing ✭✭

Thanks again Bill. I think I'm getting there. Your mention of multiple power peaks in a parallel mixed panels seems to confirm my feeling that voltage isn't limited to the lowest voltage panel. My confusion arose because almost all the websites I've found seem to come up with some variant of the following diagram, either…

Bill - thank-you for your response and please forgive my apparent continuing ignorance. In your comment you say: "For a PWM controller: Power (18 volt panel) = ~ 15 volts (operational voltage) * Current from panel Power (36 volt panel) = ~ 15 volts (operational voltage, not Vmp=36 volts of panel) * Current from panel"…

Thanks for the comments. I eventually went with two Ironridge XR 1000 rails mounted to 4" square steel tube welded to the roof support beams. No serious testing so far but the Ironridge Design Tool suggested it was borderline cat 3/4 hurricane resistant - but I take the point about flying debris. I used 18 Canadian Solar…

Do you mean 'Ejido'? Not necessarily Indian land but land owned communally by a local Ejido group. Is this an exception to the law which prohibits foreigners from owning land within 100 km of borders or the sea unless you have the bank trust/fideicomiso? I'd be interested in other workarounds for property ownership but…

LEDs don't need a series resistor if you use the correct voltage or put the correct number of LEDs in series to accommodate your voltage supply. You could probably get away with putting the two strips in series for your 24 v supply. It is a bit hotter than the 2 x 10v (20v) supplied by your original system but probably not…

Not much information to make any suggestions. Specific generator, RPM, windspeed range, power output? There are a bunch of links if you search 'custom wind generator blades'. You might also get some ideas from the blade calculator at https://www.warlock.com.au/mobile/tools/bladecalc.htm.

I have had an Air-X Marine wind generator in Baja California for over 12 years and came to the conclusion that it's best function was to warn when winds start to pick up. I was surprised when I mentioned this to other sailors who laughed and said they had come to the same conclusion. Definitely not a reliable source of…

The system is for a house in Mexico which has grid power for all but a few days per year so grid-tie seems a logical option. Outages tend to occur in the hot summers (hurricane season) when AC and refrigeration would be nice to have. As Estragon suggested, a generator seems the way to go for back-up but it would be nice to…

Thank you very much for the response mcgivor. It looks like I didn't explain well enough - about normal for me. I was thinking of 2 tubes per row of panels as I hope is clarified by the (roughish) diagram below. The dotted lines suggest a panel layout although it will depend on the dimensions of the panels I buy. I think…

Back to fridges... boring!! I did the math about 5 years back and came to the conclusion you could buy a decent solar power system with invertor and standard electric refrigerator for about the price of a gas fridge. It was for a friend who went with the electric fridge and has been very happy with it. Another issue with…

Not a question of minimizing line loss - just a question of supplying enough power to run your pump. I'm pretty sure the Shurflo will run on 11 volts (you can test it), in which case a 10% voltage drop is acceptable (but consider cable heating) and cabling much cheaper. Based on…

My goals were similar but with a sailboat. No problem with a refrigerator (details later). An additional challenge for me was the 17 amp draw of a reverse osmosis watermaker that needed to run for a couple of hours each day. We also use a small (800w) microwave. Our system has been running for about 10 years - when cost…

Re: 12v LED w/traditional screw in connect available? This company has some good products http://www.lunasealighting.com/. I've used their replacement bayonet and 2-prong LEDs for a variety of lighting and been pleased with the results. Some as bright as the halogen bulbs they replaced. Also, it's getting easier to find…

Re: Two controllers,one battery pack Update..... I ended up with a pair of ProStar-30 PWM controllers with 2 panels paralleled to each. The MPPT boxes were too big for the available space. Performance seems very good, but they are NOISY when in PWM mode. They make an audible tone at maybe (guessing here) 100-200Hz and also…

Re: Two controllers,one battery pack Thank-you very much for all the great comments and suggestions. You've really improved my understanding of contemporary solar systems. For now I'll probably go with a couple of 30A MPPT controllers with 2 panels paralleled into each.

Re: Design help needed for off grid air conditioner I have a similar sized "container" (boat) which spends a lot of time in Mazatlan, Mexico. It's pretty well insulated and sealed but has a few windows. I use a 1/2 ton (8000 BTU) window unit to keep it cool. It has an ~50% duty cycle during the day (around 90 in the…

Re: Two controllers,one battery pack Thanks very much for all of your discussions / information Cariboocoot. I really appreciate all of the contributors to these forums. Much has been clarified for me. Conventional wisdom puts me slightly under specs on panels and over capacity on batteries. I just dread shoehorning more…

Re: Sailboat PV System The answer depends on where you'll be sailing and the conditions that you're comfortable with. Even 15 kts in an anchorage can produce some pretty uncomfortable swells. I'm in the Sea of Cortez and have an Air-X-Marine rated at 300W (~25A) in 28kts of wind. The turbine power output drops with the…

Re: Two controllers,one battery pack The story of my life! !8) But having someone point out my waywardness helps me straighten out - thanks! All of the batteries are gel type - just one is a different capacity. Gels were there when I bought the boat and I replaced with matching ones. At the time, I understood that Gel…

Re: Two controllers,one battery pack Thanks for the good info, Cariboo. I have a pair of 4D Gel-type batteries (183Ah each) and a group 31 (97Ah) giving me about 460 Ah of deep-cycle capacity. I understand that battery life is improved if they are not discharged beyond 50% and that the last 10 - 20% of the charge isn't as…

Re: Two controllers,one battery pack I had basically the same question for a boat with 4 * 135W Kyocera panels,which seems to be a baby system compared with most discussed here. I had separate Flexcharge controllers for each panel (2 * 14A and 2 * 25A). They seem to be the on/off type until they died. Now I'm trying to…