We bought a used 2021 ranger R29S. The previous owner upgraded to a 270W solar panel with 4 12V/125AH AGM batteries. We live in the PNW. We want to have our boat on our mooring ball for a few weeks to keep from burning more fuel back and forth to the dock this summer. The only thing that I can think to consume some power is the navigation lights and the bilge pump. The question I have is what is a conservative estimate of how long could we keep it at the mooring ball without draining our house batteries?
newbie question on solar power
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FDRMaine
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I would say you could keep it on the mooring ball indefinitely as long as you have turned off everything. You shouldn't need nav lights on the mooring. The bilge pumps are not "switched" (except for override switches) so you can't turn them off, and wouldn't want to (except by pulling their fuses). The only risk would be if you actually had a leak and the pumps had to run, they would drain the batteries eventually. You could look into getting a remote communication system (Active Captain, Siren ect.) that could notify you in the event of the batteries getting too low, or the water level in the bilge rising. These can also monitor intrusion, drifting, temperature etc.
scross
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In most areas you are required to have an anchor light on after dark when at anchor or mooring. Some designated mooring areas do not have such a requirement. I’d recommend having the anchor light on after dark regardless of being in a designated mooring area.
If you have a LED anchor light, they don’t draw much power. A MarineBeam LED anchor light draws about 2 Amp/Hrs per day. Your solar system should be supplying 50-70 Amp/Hrs on a typical sunny day.
I have a 335 watt VE solar set up and leave the boat on the trailer with the refrigeration on low for weeks at a time during the PNW summer without any problems.
My guess, and it’s a guess, is that you would be fine leaving a LED anchor light on 24x7 with a 275 watt solar system if all other non-always on systems are turned off. Try it for 4-5 days and see how your battery voltage tracks!
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Thanks. I don't think ours anchor light is LED, but that is an easy fix.
Eagle 2
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You can simply add an all around LED light with a dedicated solar panel 10-15 watt, that would sit on top that should suffice all concerns. They are readily available on Amazon.
serendipity
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We keep our 2023 R27 LE on a mooring in Marion, MA, and have no problems keeping our batteries at 100%. We have 350 watts of solar (2x175).
However, we shut everything off except the auto bilge pumps. We do not keep the LED anchor light on, as the mooring field is large and we are in a less traffic area.
While we may get more solar potential in our region, we experienced the same result when we had only one 175 watt panel. On our prior boats, we had traditional wet cell batteries ( up to 600 amps) with no solar, and never had problems being on the mooring for extended periods: note that we kept systems except bilge pumps off.
However, we shut everything off except the auto bilge pumps. We do not keep the LED anchor light on, as the mooring field is large and we are in a less traffic area.
While we may get more solar potential in our region, we experienced the same result when we had only one 175 watt panel. On our prior boats, we had traditional wet cell batteries ( up to 600 amps) with no solar, and never had problems being on the mooring for extended periods: note that we kept systems except bilge pumps off.
Thanks that is helpful!! Most people hear about the rain in PNW but that really is only all winter long. Lots of sun in the summer months. We checked yesterday and we do have LED nav lights. I don't see in the summer that we would leave it on our mooring for extended periods this summer, so I feel more comfortable. Of course we will have our roam software alarm set and monitor it from shore.