Power Saving Tips

[ranger58sb]

Originally Posted by DeborahLee

I can also tune in the weather saving turning on the VHF and charging my cell phone with the USB port.

Leaving your VHF off ranges from false economy to potentially dangerous.

IMO.

Much easier for negotiating graceful passings/crossings/overtakings, etc... but also consider that your radio is also a safety device for other nearby boats.

-Chris

[UNCIVILIZED]

I'm curious to know what your charging setup is, & pardon me if I missed it? But the reason I ask is that when I lived on the hook, I had one 15yr old, 3 square foot, solar panel. And it alone would give me enough juice to watch 2 hrs of TV, as in the old style CRT (13" color) TV. In addition to being able to listen to as much radio as I liked, & read all night via incandescent bulbs. And only occasionally would my batteries run a touch low.
Which was easy enough to fix via hoisting my Redwing Wind Generator for 1/2 day, maybe once a week in the Winter.

So where's your big draw, & what's feeding your battery bank?

[FSMike]

Originally Posted by ranger42c

Leaving your VHF off ranges from false economy to potentially dangerous.

IMO.

Much easier for negotiating graceful passings/crossings/overtakings, etc... but also consider that your radio is also a safety device for other nearby boats.

-Chris

Last I heard monitoring vhf ch. 16 was mandatory while underway in the waters of the USA.

[ranger58sb]

Originally Posted by FSMike

Last I heard monitoring vhf ch. 16 was mandatory while underway in the waters of the USA.

I've always been taught that, too, but... I don't find a quick reference that would be applicable to all boaters in the current COLREGs.

There is no requirement there for most boats under 20m (with exceptions like towboats) and other boats in work-related roles or within VTS areas to even have a VHF radio on board. OTOH, for those boats/ships where at least one radio is mandatory, the language does address listening watches.

Most of the radio discussion is in 33 CFR 26.

Still, I believe monitoring VHF 16 is a good safety practice that should over-ride the idea of saving electrical power if at all possible, and that was the original point I was trying to make. The boat "right over there" might be in some trouble... and they probably won't know my cellphone number.

I note (without criticism) from trying to arrange safe crossing or comfortable passing that it seems quite common that sailors either don't have their radio on, don't have it set to monitor VHF channel 16, or it's on but below decks (e.g., at a nav station) and the helmsman or crew can't hear it. (Yo, sailboat, if you'd like a slow pass, slow down for a minute, I'll pass at dead slow, and all will be well. Yo, sailboat! Yo, sailboat? Anybody home?)

I note also (ditto) that powerboaters at high speed often can't understand the radio chatter due to engine and/or wind noise. (A similar ditto.)

The world is not perfect...

-Chris

[a64pilot]

My hand held seems to use very little power, and for those that only weekend, will easily last all weekend.
I assume the built in VHF uses more power.

[rwidman]

Originally Posted by ranger42c

Leaving your VHF off ranges from false economy to potentially dangerous.

I agree. If you are in a position where you need to save power by not using your VHF, you need to consider upgrading your electrical or charging system.

[DefinitelyMe]

It's all opinion of course, but these are the things i've done that i think made a big difference, in order of how much impact it made for me:

Lights changed to LEDs or CFLs. Especially the anchor and tri-colour lights. Massive difference!

Installed extra insulation in the fridge compartment. Big difference. (smaller compartment though as i just lined the existing box with more foam)

Laptop with a solid-state drive. Noticeable difference, but i don't have it on much anyway so not huge for me.

Of course there are also those standard practices that one can do to minimise power consumption - switching off lights when you're not using them, only turning on nav equipment when you're using it and especially minimising radar usage (this is a biggie).

[Foolish]

The best way to save power is to turn things off.
-If you are on deck, why do you need radar or ais? You've got eyes. Turn them off until you go below.
-What the heck are you doing with a laptop turned on more than 10 minutes a day to get the weather? You're sailing - not at the office.
-Your GPS? Why do you need to stare at it all day long. Turn it on. Figure out where you are and turn it off again.
-VHF? I can't stand the noise.
You took up sailing to get away from the world. Don't drag it along with you. Turn off everything that is not necessary for your enjoyment of sailing. If you want to stare at computer screens, take up the X-Box as your hobby.

As for charging, remember that when on the water you only want to charge up to 80% battery capacity.

[Saltyhog]

Originally Posted by Foolish

As for charging, remember that when on the water you only want to charge up to 80% battery capacity.

Why in the world would you want to do that? If you have a way to top them off: solar, wind, you happen to be motoring, whatever, top those puppies off. They'll thank you with longer service life.

[Foolish]

Why in the world would you want to do that? If you have a way to top them off: solar, wind, you happen to be motoring, whatever, top those puppies off. They'll thank you with longer service life.

Nope, you are definitely wrong on that point - when sailing. (If you are motoring, then why bother even asking this question.) Batteries charge by sucking up power. That is, you can't "push" power in; they "pull" it in. The further depleted they are, the faster they pull power in. The fuller they are, the slower they suck in. This is a very significant thing. It is much faster to charge a battery from 70% to 75% than it is from 80% to 85% and MUCH faster than from 90% to 95%. Getting to 100% is nearly impossible underway.

ALL racers are well aware of this and use their charging systems accordingly. So, when sailing, yes you can leave your solar panels charging all the time. And if the wind generator is not causing drag, then you can use it all the time. But it is very wasteful to use your engine to top off the batteries when underway. Your Watt to fuel ratio drops dramatically.

By the way, this all is moot if you are using the new and expensive lithium batteries that can charge to 100% easily.

[rwidman]

Originally Posted by Foolish

The best way to save power is to turn things off.
-If you are on deck, why do you need radar or ais? You've got eyes. Turn them off until you go below.
-What the heck are you doing with a laptop turned on more than 10 minutes a day to get the weather? You're sailing - not at the office.
-Your GPS? Why do you need to stare at it all day long. Turn it on. Figure out where you are and turn it off again.
-VHF? I can't stand the noise.
You took up sailing to get away from the world. Don't drag it along with you. Turn off everything that is not necessary for your enjoyment of sailing. If you want to stare at computer screens, take up the X-Box as your hobby.

As for charging, remember that when on the water you only want to charge up to 80% battery capacity.

All the things mentioned are useful. You could probably do without radar but the others are worth the power they consume, especially the VHF. It's a safety device and pretty much the only way another vessel can get in touch with you.

Your advice on charging batteries to 80% makes no sense at all. You'll get longer life and the power you paid for by charging them to 100%.

[Foolish]

Your advice on charging batteries to 80% makes no sense at all. You'll get longer life and the power you paid for by charging them to 100%.

I studied this issue extensively when I was writing my singlehanded tips book. And I confirmed it all with Bruce Schwab (two-time circumnavigator who is now in the battery industry). As well, I am in the solar power industry and I work with batteries every single day for my job.

You can reduce the life of your battery by taking it down to the bottom end of its range too many times. You do not reduce the life of your battery by not getting to the top end of its range. What this means for charging is, for example, that you are best to get down to say 60% and bring it up to 80%, 3 times a day. You don't want to let it drop to 20% too many times, but it will do no harm to let it drop that far once in a while.

If you are using your engine or a generator to recharge your batteries while you are sailing, then you will be wasting a ton of fuel trying to get to the top of the charge range. You are much better to charge just to 80%, and do that two or three times a day. Charging is very slow after that point.

[Dockhead]

Saving power is like saving money. It's all very well and good -- of course, if you can find obvious wastage, then eliminate it. But that's the margins only. If you have a power deficit, then it's no different from a persistent money deficit -- you can save all you want, but at the end of the day, you're going to need to produce/earn more if you want to solve the root problem.

[Dockhead]

Originally Posted by Foolish

I studied this issue extensively when I was writing my singlehanded tips book. And I confirmed it all with Bruce Schwab (two-time circumnavigator who is now in the battery industry). As well, I am in the solar power industry and I work with batteries every single day for my job.

You can reduce the life of your battery by taking it down to the bottom end of its range too many times. You do not reduce the life of your battery by not getting to the top end of its range. What this means for charging is, for example, that you are best to get down to say 60% and bring it up to 80%, 3 times a day. You don't want to let it drop to 20% too many times, but it will do no harm to let it drop that far once in a while.

If you are using your engine or a generator to recharge your batteries while you are sailing, then you will be wasting a ton of fuel trying to get to the top of the charge range. You are much better to charge just to 80%, and do that two or three times a day. Charging is very slow after that point.

This is correct.

The last 20% is not for generators. But for solar, shore power, or a long passage under motor.

I actually bought a little Honda suitcase generator to put in the last 20% for when I'm about the leave the boat. Because it makes no sense whatsoever to run a 6.5kW diesel generator for hours putting out 300 watts to get that last bit into the batts.

And that is exactly what I do -- several shallow discharges a day, rarely letting the charge fall below 60% or 65%, but shutting down the generator when the batts get to 80% (when the charge current is over 29 volts in absorption).

[Greenhand]

Originally Posted by Ann T. Cate

cwyckham,

Some time before you head offshore for good, deal with the insulation on the fridge: that will serve you very well in the tropical zones which have so much appeal.

We have some friends in Tasmania who have done this, and some of the new insulation materials are really good, light weight and easy to work with.

If you enjoy a bilge temp. beer where you are, you'll want cold further south! ;-)

Ann

The issue isn't the materials, it is access to the spaces. We figure we will have to rip out the counter tops, if not more.