Solar Panel

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WindMaiden

Member
Joined
Jun 27, 2024
Messages
11
Location
Mexico / WA
As we keep looking for a trawler, I am surprised that none of the ones we saw had solar panels, and most of the ones I see for sale don't either. It's strange because most sailboats at this point have solar panels, even in the rainy PNW. Is it because a trawler just uses too much energy between the huge fridge and freezer (my wife couldn't believe the difference compared to our sailboat) or is it just a different culture? If any of you have solar panels for a 44 ft trawler, what would be needed at anchor (mostly fridge, freezer, Starlink)?
 
Probably because power boats have much more capability to create electricity than sail boats do. Unless you are planning on staying on the hook for extended times solar power isn’t necessary. Lots of people travel from marina to marina and don’t anchor much so lots of battery power isn’t needed. To each their own so to speak. If you want solar power on your boat you will likely have to add it yourself.
 
We did not have solar panels, but I installed them myself. We now have 3.2 Kwp in solar (8 panels total) and they are capable of charging the batteries, but also operate all the systems we have on board. So while I am charging I can also run the water maker, dish washer, airco etc. Not all at the same time of course, but if I stagger it a bit it works out fine.
Obviously that is now in the summer, when there is ample sun shine, but when the days get shorter also our needs go down a bit. No need for airco, water consumption goes down (lot of swimming during the summer means increased shower water), so it all works out pretty nice.
Normally don't need the generator anymore, nor do I need shore power, so can highly recommend installing a lot of solar. It is not cheap, but it gives you a lot of freedom and increases the range of the boat. All the fuel for the generator can now be used for the engines.
 
We added solar to our trawler. We already had a huge house bank and could last a weekend no problem, but the solar makes a big improvement. We can stay almost indefinitely without starting the genset. (If the sun is out)
 
If you plan to live aboard in the PNW you'll likely want to build out a solar system that is not too intrusive on your living/flybridge space, would help reduce generator run time in the summer when on the hook.

Typically we run 4 to 6 hours between anchorages, that usually lifts the house bank full, especially with my 4 panels. But the sun doesn't always shine, if so, I run genny for a few hours every couple of days.

You need to get on board to know your watt hour consumption lifestyle and then learn to manage use and charging. We don't leave starlink on all day or night, and almost all lights are led now.

If you get moorage say in Friday Harbor for a couple days to provision figure on $80/night at the dock for 44 footer.

Good luck finding your trawler and moorage. Slips in my moorage can transfer to new owners, so look for that.
 
We have 520w of solar and will add 300 more before the coming winter season.
 
We had solar on our 37 Nordic Tug (over 40 feet overall) that I added to the pilothouse rooftop. They were "flat" and not adjustable. In the summer (May to mid Sept) on most days (no heavy cloud or fog), the solar was able to totally recharge our house bank to 100% (full charge so good for the batteries which were lead acid golf carts). We only started the generator when we wanted hot water for showers, or if the sun was not cooperating :).
We had 2 - 285 watt (570 watts) monocrystalline panels with an MPPT controller charging directly a 660 ampHr house bank. Our electrical use consisted of fridge with freezer, an additional small freezer, lights (led), water pump, sometimes small fans, sometimes DVD player, with AIS left on for an anchor alarm. We operated pretty much a 12V boat and only used the inverter when underway to power the laptop, etc. Propane cooking. We anchored out alot mostly in west coast of BC waters.
Hope this info helps.
 
Two reasons trawlers are less likely to have solar. First the OP touched on- significantly greater power demand is often the case (though many new sailboats have similar creature comfortable analogous to powerboats - I'm thinking Condo-marans). For years, a 40-foot monohull could live in a 150AH (12v) budget. A 40-foot trawler will easily consume 3x or more in a 24-hour period.

Second Comodave touched on - powerboats often power more and have larger alternators and frequently generators and can recharge a battery bank quickly.

That said, solar is becoming pretty common in powerboats. Cheap lithium and solar modules make the business case simple and relatively inexpensive to add. For many who boat in areas where AC isn't needed, solar with a large battery bank is a feasible replacement for a generator.

Good luck with your search.

Peter
 
This is my first summer with 400W of solar. For the first month, I don't think I got 100AH total, rain and clouds dominated. When the sun came I out, I actually broke even for about 10 minutes. I saw a peak of 339W for a very short time in mid day. I would say on a trawler with a Starlink and all the other devices, I would look for about 600W. I may add another 200 next year.
 
This is my first summer with 400W of solar. For the first month, I don't think I got 100AH total, rain and clouds dominated. When the sun came I out, I actually broke even for about 10 minutes. I saw a peak of 339W for a very short time in mid day. I would say on a trawler with a Starlink and all the other devices, I would look for about 600W. I may add another 200 next year.
what is your total need for 24 hours? I have 440w in a box for 3 years now I never installed on the GB. It would have worked well there as the stove was propane and l did not have the large power need this boat requires. I need 350Ah per 24 on average and no way is 400 watt system is going to support that. So far I am avoiding installation. But since I have a generator is it worth it to go enough solar.
Maybe I represent why most do not have solar.
 
I installed one 265W panel on my PH roof. It was the biggest I could fit there without moving the existing air horns and spotlight. I could have added more on the rails surrounding my boat deck but didn't want them being in the way.

During the summer in decent weather that panel can keep up with refrigeration, head, holding tank aerator, anchor and cabin lights. It can't keep up with inverter use for coffee maker and wife's CPAP.

So typically we run the genset a couple times a day. This provides AC for inverter heavy coffee loads in the morning and recharges the batteries in the morning after running the CPAP. It also allows us to heat the water heater for showers and dishes.

This is if we are sitting on the hook. If we are on the move during the day then we generally don't need to run the genset. The alternator and solar can keep up with our usage.

So I view solar as a way to reduce genset time and a way to keep the batteries topped up when out and about. It has proven to be well worth the nominal cost to install that panel.
 
Steve, 440watts of panel,assuming 8 hours of sun, and assuming 50% output, could extract nearly 150 amps a day. Surely that`s worth reduced genset/alternator run time. Especially as you have the panels sitting in a box. You just need some mounts, wire, fuses and regulators and you might already have some of those.
 
As we keep looking for a trawler, I am surprised that none of the ones we saw had solar panels, and most of the ones I see for sale don't either. It's strange because most sailboats at this point have solar panels, even in the rainy PNW. Is it because a trawler just uses too much energy between the huge fridge and freezer (my wife couldn't believe the difference compared to our sailboat) or is it just a different culture? If any of you have solar panels for a 44 ft trawler, what would be needed at anchor (mostly fridge, freezer, Starlink)?
Hi I have 2700w of Solar on my passage Maker 56 and every electric appliance you could imagine including 70 inch TV multiple fridge freezers full size computers three air-conditioners dive compressor 240 V hot water 240 V water maker, on a sunny day I can run anyone of these independently through my solar without even touching my 1800 amp hours of battery.
 
Hi I have 2700w of Solar on my passage Maker 56 and every electric appliance you could imagine including 70 inch TV multiple fridge freezers full size computers three air-conditioners dive compressor 240 V hot water 240 V water maker, on a sunny day I can run anyone of these independently through my solar without even touching my 1800 amp hours of battery.
I would Have at least 1000 wants to keep those items running double would be better so you are not chasing it constantly and at least 1000 amp hours of battery.
 
Two reasons trawlers are less likely to have solar. First the OP touched on- significantly greater power demand is often the case (though many new sailboats have similar creature comfortable analogous to powerboats - I'm thinking Condo-marans). For years, a 40-foot monohull could live in a 150AH (12v) budget. A 40-foot trawler will easily consume 3x or more in a 24-hour period.

Second Comodave touched on - powerboats often power more and have larger alternators and frequently generators and can recharge a battery bank quickly.

That said, solar is becoming pretty common in powerboats. Cheap lithium and solar modules make the business case simple and relatively inexpensive to add. For many who boat in areas where AC isn't needed, solar with a large battery bank is a feasible replacement for a generator.

Good luck with your search.

Peter

We spend about 8 months of the year on the boat and especially during the summer we can stay 1 or 2 weeks in an anchorage, just enjoying the weather, bit of swimming etc. We do have 2 large alternators, but those days on anchor the engines are not running. Obviously we then still need to be able to run all the systems onboard and for that matter I have installed the large solar bank as well as a large lithium bank. And must say it has worked out nicely, we have not used the engines or generator at all, the solar panels were keeping the batteries charged while still using all equipment onboard. During daylight hours we get about 2.4 to 2.5 Kw per hour out of our 3.2 Kwp solar bank. That is about 80 % efficiency and am happy with that. Never seen 100 % and guess I never will.

In the colder months we don't spend that much time on anchor in one particular spot, maybe we stay for a couple of days and then we don't need shore power, which is great. Here in the Med cities and marinas have figured out that charging an arm and a leg for 1 Kwh is a nice source of income. We have seen marinas where they charge 2 - 3 USD per Kwh and you are not allowed to run the generator. So that adds up quickly if you need about 10 - 15 Kw per night to run the boat. That 'problem' no longer exists for us.

Agree that if you don't want to have your whole boat air conditioned you can easily run if off solar and a large battery bank. We do have a 35 amp air conditioner in the master, so if we want to use some airco at night we still can, it won't kill the battery bank and the solar panels will replenish it quickly during the day.
And indeed, the moment we start up the engines the batteries will be full in a few hours, which is about the time we need to get to the next place of interest.
 
Steve, 440watts of panel,assuming 8 hours of sun, and assuming 50% output, could extract nearly 150 amps a day. Surely that`s worth reduced genset/alternator run time. Especially as you have the panels sitting in a box. You just need some mounts, wire, fuses and regulators and you might already have some of those.
Thanks Bruce, for now it sits at the bottom of the to do list as a maybe if I need something to do. They are 4-100w panels. yes I chewed over the numbers and have not yet come to the conclusion for it to be an enough benefit for right now. The GEN needs the exercise
 
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