Charging electronics off inverter on charter boat

[doctorbill]

We're taking a bareboat charter on a boat without a genset. Its been some years since we chartered without a generator and it seems I have a LOT more charging needs since the last time (laptops, phones, radios, cameras, drone, etc) so I was wondering a few general concept issues ahead of time to best plan for our needs.

Charter boats typically require you to idle or run the engine ~2-3 hrs per day to maintain housebank charge for refrig, etc. What is the effect of running the inverter whilst charging the housebank? Is it significant if I use this time to also power up the electronics? Or am I better off charging up the housebank and then running the inverter when the engine has already completed its housebank top off? I know there is a lot of details that matter, like especially the housebank size. This is a standard 43 foot older monohull from a major charter company, so I would assume a standard housebank of AGM's.

General ideas on how to go about this? I'm really bad with 12V electronics
stuff.

[silvercreek]

Portable consumer electronics use very little power to recharge. I wouldn’t worry about it. Most can be plugged in to usb though, which would be more efficient than going off the inverter, if possible.

[RickG]

Definitely charge everything when you are charging the batteries. We generally run the engine on charter boats when we are under sail with the transmission in neutral at 2,000 RPM. The charge acceptance rate is likely lower than a stock 85 amp alternator will put out. No solar, I assume?

Cheers, RickG

[doctorbill]

Makes sense!

Have to assume no solar on a stock charter fleet boat in BVI.
I’ve seen some with a small built in solar but I assume this is a starter batter trickle / maintainer.

[RickG]

The boats out of the Waypoints / former CYOA fleet on St. Thomas all have solar. A lot of it depends on where you are cruising. Newer boats are coming off the factory floor with solar, gen, air, and a watermaker.

Cheers, RickG

[Wolfe10]

Do NOT just run the engine at idle speed for charging. In neutral and at least 1,500 RPM.


Much better amp-hrs to the batteries/gallon of diesel.

[El Pinguino]

Originally Posted by doctorbill

We're taking a bareboat charter on a boat without a genset. Its been some years since we chartered without a generator and it seems I have a LOT more charging needs since the last time (laptops, phones, radios, cameras, drone, etc) so I was wondering a few general concept issues ahead of time to best plan for our needs.

Charter boats typically require you to idle or run the engine ~2-3 hrs per day to maintain housebank charge for refrig, etc. What is the effect of running the inverter whilst charging the housebank? Is it significant if I use this time to also power up the electronics? Or am I better off charging up the housebank and then running the inverter when the engine has already completed its housebank top off? I know there is a lot of details that matter, like especially the housebank size. This is a standard 43 foot older monohull from a major charter company, so I would assume a standard housebank of AGM's.

General ideas on how to go about this? I'm really bad with 12V electronics
stuff.

Despite what has been stated in some replies most of what you have can't be charged via USB. Just the phones and ipad thingos.

I would charge via the invertor while the engine is running - the alternator should ramp up its output to cover the extra load.

So what I do - cig lighter plug with two USB outputs for phones/ ipads which is used at any old time.

I also have a small powerboard plugged into the invertor all the time but normally only switched on when engine is running. This gives me 240V ( 120 V in your case ) for everything that would normally be plugged into a wall socket at home.
In the piccy you can see my beard trimmer charger and a AA/AAA charger. Also used for my laptop, camera batts, drone batts, in fact anything that would be plugged into the wall at home.
Oh there is also a USB port on the inverter and some power boards will also have a couple of USB ports on them.
Hope this helps,
Enjoy your charter.

[doctorbill]

Awesome! Thanks for all the input guys.
Yes it really sucks to have to run engine to recharge. Nice to hear some charter boats are starting to equip solar!

[ChrisJHC]

You may also find that running the engines will also heat the water.
Running them for an hour before dinner typically works well to allow people to have showers, charge up devices and provide hot water for cleaning up.

Re using the inverter, the worst thing you can do is use AC power to charge devices that can be charged via DC/USB. You loose a lot of energy converting from DC to AC then loose more again when you convert back to DC.

Also remember to turn the inverter off when you’re not using it.

[goboatingnow]

Originally Posted by Wolfe10

Do NOT just run the engine at idle speed for charging. In neutral and at least 1,500 RPM.


Much better amp-hrs to the batteries/gallon of diesel.

It’s a charter no one cares. Small Diesel engines don’t have a issue with idle or near idle running.

[Dockhead]

Originally Posted by goboatingnow

It’s a charter no one cares. Small Diesel engines don’t have a issue with idle or near idle running.

Diesel engines without the prop engaged prefer idle to 1500 or even worse, 2000 RPM. It's higher RPM with no load which polishes bores. Because more air is pumped through for the same amount of power; cylinders don't get up to temp.


People who love their main engines and are forced to charge with them, often engage prop while doing so. At anchor you could engage reverse. Not too much power though!

[doctorbill]

Interesting discussion about how to charge house bank with engine. Now that I recall better, the last time I chartered a boat without generator or other charging options, I was told to run the engine 2 hrs in morning and 2 hrs at night, and at 1500-20oo RPM in idle. Seemed excessive amount of charging but I’m sure it depended on the draw of refrig and the bank size.

[goboatingnow]

Originally Posted by Dockhead

Diesel engines without the prop engaged prefer idle to 1500 or even worse, 2000 RPM. It's higher RPM with no load which polishes bores. Because more air is pumped through for the same amount of power; cylinders don't get up to temp.


People who love their main engines and are forced to charge with them, often engage prop while doing so. At anchor you could engage reverse. Not too much power though!

Bore polishing requires many many hours of running light. Charter boats motor a lot.

Run it for 20 minutes at 1200 rpm.

Prop running isn’t needed unless your doing this without motoring for months.

[Rumrace]

Phones and tablets wouldn’t be a problem. Do you have USB ports on board or are you bringing plug ins.
Having an international travel kit for various plugs can help. 220-120 50-60htz

[ChrisJHC]

Originally Posted by doctorbill

Interesting discussion about how to charge house bank with engine. Now that I recall better, the last time I chartered a boat without generator or other charging options, I was told to run the engine 2 hrs in morning and 2 hrs at night, and at 1500-20oo RPM in idle. Seemed excessive amount of charging but I’m sure it depended on the draw of refrig and the bank size.

Don’t forget that the charter companies cater for the lowest common denominator.

If you know how to read and interpret the voltmeter on the boat, you will find you need a lot less charging than stated.

The 1500 rpm is probably right.