While under sail at night for recharging house battery bank, do you start your engine or you start your gen? I will improve my house battery bank but now i have to start the engine every 3 hours, i try to start the gen but it does not work well with heavy sea, i do not know why. Under anchor it will work very well. So i have to start the engine and the noise down below is terrible. How do you sail at night ?
Night navigation battery recharging
- Thread starter Valerio
- Start date
LED nav lights. Just change the bulbs. Uses 1/10th the power. My 3 nav lights combined use 8 watts total, and they're equivalent light to 20 watt incandescents (60 total).
With LED's, VHF, plotter, AP, and portable compressor-fridge, I can run all night on 1 G27 batt, with another in reserve. Then solar charge all next day on 100w panel/controller.
Other tips:
Don't use radar unless really need it.
Maybe be intermittent with the chart plotter - Use the compass for awhile, then just check position on the plotter till you get close to destination. Or use a Garmin handheld at night.
You could use a wind gen.
Or a towed propeller charger. Some expense on these.
I think best is to just have a good big batt and be power conservative.
With LED's, VHF, plotter, AP, and portable compressor-fridge, I can run all night on 1 G27 batt, with another in reserve. Then solar charge all next day on 100w panel/controller.
Other tips:
Don't use radar unless really need it.
Maybe be intermittent with the chart plotter - Use the compass for awhile, then just check position on the plotter till you get close to destination. Or use a Garmin handheld at night.
You could use a wind gen.
Or a towed propeller charger. Some expense on these.
I think best is to just have a good big batt and be power conservative.
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It depends. Our engine, because of the Aquadrive and soundproofing is not that loud. It clearly is louder than the generator. The main engine has a nominal 250kw Balmar's alternator. In the real world it might put out 150 to 175 amps at higher RPMs in cool offshore air. If the engine is turning at 1800 rpm or less than 2200 rpm, the output is much lower. We have a smart regulator that will drive the alternator output up, but even wiypth that, we sometimes "fool" it with cycling the on off key without stopping the engine (that reinializes it). If we've dropped the batteries down to 60% State of charge (SOC), we can have a bunch of amp hours to return. Then, if we are,cruising, we usually would motor sail.
Keep in mind, that if you are in offshore night mode with instruments, autopilot, radar, chart plotters, computer, lights, refrigeration, etc. going, and the like, you need to deduct that background load from what gets to the batteries. (e.g., 100 amps from the alternator gets 20-30amps just handling those current loads.
We have a Westerbeke 7.6 kW constant RPM conventional that powers our Mastervolt charger (and inverter). While it is nominally rated at 200 amps, in the real world, it only puts out 135amps at bulk. (Most 130amp chargers put out 65-70 amps in bulk. They DeTuncq themselves because of interna heat build-up. It's like the old stereo amp "overstating" of output.). The Westerbeke seems to work in almost all rough weather without issues. It very quiet with our sound proofing. You can sleep with it running next to you in the dual aft cabins without difficulty. That's my preferred recharging -- unless I want a bi faster recharge and want to also motor sail. The generator uses less fuel to generate the same ah's into the batteries.
Some variable frequency generators are more finecky in rough weather in my limited experience with them. Example, the Pathfinders. They are smaller, lighter, and (in theory) use less fuel.
Keep in mind, that if you are in offshore night mode with instruments, autopilot, radar, chart plotters, computer, lights, refrigeration, etc. going, and the like, you need to deduct that background load from what gets to the batteries. (e.g., 100 amps from the alternator gets 20-30amps just handling those current loads.
We have a Westerbeke 7.6 kW constant RPM conventional that powers our Mastervolt charger (and inverter). While it is nominally rated at 200 amps, in the real world, it only puts out 135amps at bulk. (Most 130amp chargers put out 65-70 amps in bulk. They DeTuncq themselves because of interna heat build-up. It's like the old stereo amp "overstating" of output.). The Westerbeke seems to work in almost all rough weather without issues. It very quiet with our sound proofing. You can sleep with it running next to you in the dual aft cabins without difficulty. That's my preferred recharging -- unless I want a bi faster recharge and want to also motor sail. The generator uses less fuel to generate the same ah's into the batteries.
Some variable frequency generators are more finecky in rough weather in my limited experience with them. Example, the Pathfinders. They are smaller, lighter, and (in theory) use less fuel.
I will change my battery bank and i will have at 50% capacity like 300 amps. All the lights are leds, with the fridge and refri, sat nav, autopilot sound and some light i think my usage is like 25 to 35 amp/hours. So i will be able to spend nigh long without recharging. But is a 2200 us dollars for the new bank. I like many of us use our saling boat for very small amount of time outside the docks, not counting daysailing, maby i will be sailing or at anchor like 20 days in a year, i think spending on solar panels if you allready have a gen is not wise.
If you use an autopilot, instruments, freezer and refrig. Sat nav, some lights and a little musica -- you mean 25-35 ah per nigh or per hour? In an 8 hour night, I might guess a little less for you -- but I'd say 150-175 ah wouldn't surprise me.
What type of generator? Does it act up when you heeled over or just when you are pitching in rough weather? Probably a fuel issue, would be my guess. Maybe tank, maybe pump, maybe, maybe...
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It is a panda gen, i think the gen pick up tube is not all the way down into the tank and with a shaking sea it will not pick up enough fuel and starv. SG i think when you says amp/ hour i am talking about the amps you use every hour, like 25. Skipper right now i cannot afford a new house bank so i was wonderer how to sail this season. After 4 days of bad charging on my way back i had to start the engine after only 2 hours of navigation.
Why do you believe you need to charge every three hours?
What are you using to measure SOC to determine that you need to recharge every three hours?
What type of batteries AGM, GEL or flooded?
How many ampere hours of capacity is the bank? (20 hour rating)
When under sail at night what is your average load in amps?
What equipment are you running while sailing at night?
What brand & model alternator and how many amps?
Internal or external voltage regulation for alternator?
How old are the batteries?
I have a 6 monts old LTH 210 amp, but i suspect they are not really deep cicle. On the last navigation when recharging with the engine i made the mistake to rev the engine at 1600 rmp, because of the strong 22 knots, i was doing 6 knots with 1/3 of sails, open reach almost 90 degrees, short big waves, the boat was shaking side to side all night long. I have a very good charger inverter, but the last owner who just sell the boat to me change the bank with batteries that really are like start bateries. In my hunter 41 i will install 6 trojan 6 volts under the nav seat but is like 2200 usd, so this change i will make it later this year, before i will attemp to sail to isla mujeres and cozumel.
Especially when the asker answers his own question.
The legitimate question was, "How do you sail at night?" After being prefaced with battery- state of charge issues, and the fact that the genset doesn't operate properly, and he doesn't like the noise of the engine.
This was the first inquiry, prior to his disclosing loads of additional info.
I explained how I sail at night, then offered quiet and functional power alternatives, with tactical adjustments to "sail at night" power consumption.
He poo poo'ed the alternate power suggestions, stating that it would be "unwise" to invest in them, given that he has a genset. ..... But the genset doesn't work....
Sorry, I was a retail store owner for years. Running in circles makes me dizzy.
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You have not provided the answer that he wants to hear. I see only two viable options that might be acceptable to his position, either fix the generator or don't sail at night.Especially when the asker answers his own question.
The legitimate question was, "How do you sail at night?"
Sorry, I was a retail store owner for years. Running in circles makes me dizzy.
I think a logical question might be how can the OP reduce his load at night until he gets his battery conversion done, which was discussed a little. What is the largest load and can that be shut down? What is the next largest load.
1. Refrigerator/Freezer? Load up the refrigerator and freezer (once cold a full freezer/refrigerator uses less power), freeze ice when you have shore power available or the generator running (block ice works better for this) and put it in the Refrigerator then shut it off at night? You can freeze water bottles, fill up the refrigerator and use them later to drink. See if you can increase the insulation and check the door seals.
2. Like mentioned, don't run the radar unless you really need it.
3. Balance your sails and reduce the load on your autopilot or better yet, hand steer at night and turn your autopilot off at least part of the time. This is a big one, your autopilot can be a real power hog.
4. If you are in known good water (like well offshore or open ocean) turn off your depth sounder. Do you really need that info there?
5. Turn off your speed log. Do you really need that info displayed all the time?
5. Use a handheld Garmin or similar and your magnetic compass for navigation at night.
6. Turn off interior lights (they kill your night vision anyway). If you can't turn them off, make sure you have them converted to LEDs.
In short, conserve energy - every amp counts.
1. Refrigerator/Freezer? Load up the refrigerator and freezer (once cold a full freezer/refrigerator uses less power), freeze ice when you have shore power available or the generator running (block ice works better for this) and put it in the Refrigerator then shut it off at night? You can freeze water bottles, fill up the refrigerator and use them later to drink. See if you can increase the insulation and check the door seals.
2. Like mentioned, don't run the radar unless you really need it.
3. Balance your sails and reduce the load on your autopilot or better yet, hand steer at night and turn your autopilot off at least part of the time. This is a big one, your autopilot can be a real power hog.
4. If you are in known good water (like well offshore or open ocean) turn off your depth sounder. Do you really need that info there?
5. Turn off your speed log. Do you really need that info displayed all the time?
5. Use a handheld Garmin or similar and your magnetic compass for navigation at night.
6. Turn off interior lights (they kill your night vision anyway). If you can't turn them off, make sure you have them converted to LEDs.
In short, conserve energy - every amp counts.
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Thanks Smokey, easer to say that to get done, after having many old sailboat with few ameneties, we are very happy with our hunter 41, my sons and wife feel sailing boring, and as many teenager the must steer at some kind of screen. So they love to play music see the tv, play some nintendo games an so on. I live in the tropics, near cancun on the yucatan peninsula. the weather is very hot, when the ice is gone is the time to get back to the doc. There is no life without fridge. jajaja. For instance on a four day trip we carry 200 ice cooler with 20 bags of ice. I use to have on the walking light on the floorall night long as a safe measure so we do not need the head light to move around, all leds. I think i will set up the autopilot for less correction it is moving all the time. One question if i have a split screen and i am not lookin at the depth sounder doest it mean is not on ?
i have a small panel with three light, full, medium and low, also i have a voltimeter on the main panel and when i see lower than 12 volts is time to charge.
Wow, I am assuming you and your family "live" on your boat. All the "screen" stuff except the TV and maybe DVD should be on its own power and shouldn't impact your battery. Sounds like you need to introduce your family to the concept of "books" Like you said though may be easier said than done. It looks like they need to "unplug" a little but that may be hard to get done.
Considering what you've described as the "necessary" loads that "have to stay on" turning off the depth sounder or any instruments other than the autopilot isn't going to do much for you compared to "family" loads. Even at that, they can't possibly be on that equipment ALL night long so something sounds amiss. You should see what the loads are with the "navigation" equipment on are and record those. Drop some of those that you can and see where you are. Get a good Battery Monitor and so you can see your loads, voltage, and state of charge. Set a "limit" on the "family" load you are willing to accept to limit the need to run the engine or generator and set some rules.
I see no other way out other than that or upgrading your batteries and charging systems. Sailing is not generally conducive to a "plugged in" lifestyle. Seems counter to the idea. If you don't control loads and charging (treating your batteries "right") you are destined to ruin any new batteries you install. Study the stuff from Mainesail (Compass Marine) on his website and take it to heart or be destined to be a power boat with sails rather than a sailboat with auxiliary power.
Like you said though may be easier said than done. It looks like they need to "unplug" a little but that may be hard to get done. Considering what you've described as the "necessary" loads that "have to stay on" turning off the depth sounder or any instruments other than the autopilot isn't going to do much for you compared to "family" loads. Even at that, they can't possibly be on that equipment ALL night long so something sounds amiss. You should see what the loads are with the "navigation" equipment on are and record those. Drop some of those that you can and see where you are. Get a good Battery Monitor and so you can see your loads, voltage, and state of charge. Set a "limit" on the "family" load you are willing to accept to limit the need to run the engine or generator and set some rules.
I see no other way out other than that or upgrading your batteries and charging systems. Sailing is not generally conducive to a "plugged in" lifestyle. Seems counter to the idea. If you don't control loads and charging (treating your batteries "right") you are destined to ruin any new batteries you install. Study the stuff from Mainesail (Compass Marine) on his website and take it to heart or be destined to be a power boat with sails rather than a sailboat with auxiliary power.