by seadago » Wed Sep 20, 2017 10:52 am
Hi everyone
Ok, here it is finished, at last!
Boat. Freedom 30 CK (Hoyt), '82
Total Panel Output; 400 Watts nominal in total
Panel Size: 1050 X 540 mm each. Have four in all, installed in two separate arrays.
Panel Location: Cabin roof. Location was determined by lack of space elsewhere. However, required re-directing all the rigging from the main mast, which run along the middle of the cabin roof. There is quite a bit of shading from booms and sails. How much exactly, I still can't ascertain in watt terms. In sizing the array, I allocated 20% wattage loss caused by shading. Only foreseen potential problem is the occasional need to step on the cabin roof. Panels are supposed to cope with this though.
Type and Brand of Panel: Elfeland, 100 watt nominal each, monocrystaline, semi-flexible. Have to be, as they needed to fit on a slightly convex coachroof. Chinese el chippo panels, bought on eBay.
Total Cost: About 800 GBP in total. This is only HW - not counting my labour!- Panels were 400 GBP for four. This is for the array.
Measured Efficiency: So far happy in the sense that, moored in a marina but living onboard, the array supplies in excess of daily budget (including running the fridge 24X7). Managed to get 7 Amps from each array (i.e. from two panels) in full sunshine. In October, in the UK, that's not bad. Expect at least double that in any climate fit for human habitation. Anyway, very happy not to have to connect to shore power (or run the engine) when moored!!!
Install: Four 100 Watt nominal panels connected in parallel and wired in two separate, independent arrays; port and starboard respectively, each with its own controller. Reasons for this design are: (1) wish to have 100% redundancy in case of critical failure in one of the arrays, (2) simplify and minimise wire runs to the batteries. In my case, I have two banks of domestic batteries (2X 110 Ah), under the port and stbd bunks respectively. There is a circuit breaker isolating each panel, and a 30 Amp breaker before each battery bank.
- Attachments
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- wiring on the cabin roof. Looks a bit messy, but will be tidied and hidden when I replace the lining!
- cabin roof cabling.jpg (174.89 KiB) Viewed 636 times
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- one MPPT controller per array, isolation switches on each panel
- controller and pv switches2.jpg (37.14 KiB) Viewed 636 times
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- panels connected in parallel, in two separate arrays, port and stbd respectively
- array full view2.jpg (180.93 KiB) Viewed 636 times