Just purchased first boat, but i have some questions.

[tnewson]

Hi there,

 

I have just purchased my first boat and it is a 22ft GRP cruiser. Im really quite confused about how im going to make my electricity last...

 

The boat is going to be moored up most of the time and there is a communal generator which runs for 2 hours per day and produces 3.7kw. A few boats hook upto this including mine.

 

Im just wondering how would i go about making it possible to run my laptop, tv, xbox 360, lighting, either speakers or a stereo and a spare plug to charge my phone . Not all at the same time but im just wondering how long this would last me?

 

Also, i understand that cruisers can be difficult to keep warm in the winter so is there a way to insulate them?

 

 

Thanks alot

[bottle]

Welcome

 

It is doubtful you will.

 

Two hours of supply from a shared 3.7Kw generator (?240volt) will probably only run a charger (depending on the number of users) for your domestic batteries and two hours charging will not be enough.

 

or

 

Do you get two hours of personal use, if so you could run all that stuff for two hours.

[Proper Job]

It would really depend on your charging set up and the size of the domestic battery bank.

 

You then need to look at your demand on the said battery bank (how much for how long).

 

What charging facilities do you have other than the communal supply?

 

The best bet is to try it out. You can then either improve the system to meet your demand or reduce your demand to meet the system capacity

[tnewson]

Its 2 hours shared charging... hmmm.. I may have to buy a generator!

 

I was looking at one of these batteries.. do you think it will be enough?

 

http://cgi.ebay.co.uk/LUCAS-110AMP-SEALED-...2|39:1|240:1318

 

 

Also, i have heard that to make a battery last as long as possible you should never drain it to less than 25% capacity at the maximum. how effective would a solar panel trickle charger be to reduce this?

 

Cheers for the replys

[onthecut]

Hi there,

 

I have just purchased my first boat and it is a 22ft GRP cruiser. Im really quite confused about how im going to make my electricity last...

 

The boat is going to be moored up most of the time and there is a communal generator which runs for 2 hours per day and produces 3.7kw. A few boats hook upto this including mine.

 

Im just wondering how would i go about making it possible to run my laptop, tv, xbox 360, lighting, either speakers or a stereo and a spare plug to charge my phone . Not all at the same time but im just wondering how long this would last me?

 

Also, i understand that cruisers can be difficult to keep warm in the winter so is there a way to insulate them?

 

 

Thanks alot

 

Not clear from your post --- are you on the boat full time or only sometimes ? If it's only sometimes I'd add some extra batteries so you have a decent 'reservoir' of electricity, which your communal charger will then catch up on in your absence.

Depending on budget and location, you might also consider a wind generator and / or solar, although these are quite expensive to set up and you do want to be sure they would work in your mooring. Bit of a pain, but if you have a car, you could rig up a charging cable and have a loose battery that you plug in, in the car when you're driving and carry back to the boat. Not ideal, but better than darkness. If you browse the forum there must be hundreds or more of posts on electricity -- you'll not be bored !

 

Mike.

[alan_fincher]

Also, i have heard that to make a battery last as long as possible you should never drain it to less than 25% capacity at the maximum.

You should never take a lead acid battery below 50% of ot's quoted capacity, or you will quickly damage it.

 

If you are suggesting it's OK to take 75% of the charge out before recharging, then that is wrong, and it will not have a long life.

[Proper Job]

Its 2 hours shared charging... hmmm.. I may have to buy a generator!

 

I was looking at one of these batteries.. do you think it will be enough?

 

http://cgi.ebay.co.uk/LUCAS-110AMP-SEALED-...2|39:1|240:1318

 

 

Also, i have heard that to make a battery last as long as possible you should never drain it to less than 25% capacity at the maximum. how effective would a solar panel trickle charger be to reduce this?

 

Cheers for the replys

Another thing you need to consider is what type of charger you are intending to use? Irrespective of how you get your 240 volts (you own genny or the communal one), you need a decent multi stage charger link (other makes are available) and not a 'normal' car type battery charger.

 

The battery you have identified is a 'sealed for life' battery. It can be used (I have four of them), but it will take longer for a given charge cycle as you need to charge at a lower charge voltage. If 'time is of the essence', go for maintainable ones that you can top up.

 

As you will no doubt be gathering - its not as straight forward as you think

[chris w]

Let's run the maths.

 

3.7KW for 2 hours is 7.4KWH (assuming 100% efficiency). At 14.2v charging voltage that's a total of 521 Ampere Hours (AH) available to all boaters at your mooring.. So, at a typical 70% charging efficiency that's 365AH into the actual batteries.

 

Let's say that is shared between just 6 boats, that's about 60AH each total. If it's 12 boats that's only 30AH each. If it's 20 boats etc etc etc

 

Either way, your usage will have to be very light to get any meaningful charge back into your batteries and, even then, the batteries won't be fully charged so their life will be shortened.

 

Having MORE batteries won't solve the problem. For sure, you will be able to run your appliances longer the first time before the batteries need a recharge, but you will then have an even larger charging deficit to overcome, making the situation even more impossible.

 

The only real solution is to buy a generator and a proper multistage charger (not a "car" charger type). I also agree with "Proper Job" above that you can charge a wet lead-acid battery faster because you can charge it at a higher voltage. Sealed batteries are good for sea-going yachts with large heel angles.

 

Chris

PS: fibreglass cruisers are freezing in winter - I used to have one. I never used it between October and March. IMHO, it's not safe to use a wood stove inside a fibreglass boat. An insulated steel narrowboat is a joy all year.

Edited April 28, 2009 by chris w

[Naughty Cal]

Hi there,

 

I have just purchased my first boat and it is a 22ft GRP cruiser. Im really quite confused about how im going to make my electricity last...

 

The boat is going to be moored up most of the time and there is a communal generator which runs for 2 hours per day and produces 3.7kw. A few boats hook upto this including mine.

 

Im just wondering how would i go about making it possible to run my laptop, tv, xbox 360, lighting, either speakers or a stereo and a spare plug to charge my phone . Not all at the same time but im just wondering how long this would last me?

 

Also, i understand that cruisers can be difficult to keep warm in the winter so is there a way to insulate them?

 

 

Thanks alot

 

Hi

 

We have a 25ft GRP cruiser that is hooked up to shore power whilst in the marina but uses a leisure battery whilst we are our cruising. We have a big inboard engine with a fairly hefty alternator so charging the batteries whilst out cruising isnt a problem. Our main power consumption is from the fridge, we use LED lighting, a low power consumption TV and every now and again the heating if it is cold enough to warrant it. We dont have a power problem and we only have 1 leisure battery on the go.

 

We have used our boat all this winter and even on the coldest nights when the marina/river/canal has frozen over we have just switched on the heating closed all of the curtains and watched TV in the warmth. We havent found the cold to be a problem. It can be a little chilly first thing in the morning but one of us braves it for a second to turn on the heating then we go back to bed for half an hour and when we get up the cabin is toasty again. Our boat isnt insulated but it does have vinyl in certain places to reduce the heat loss and double skinned construction with air trapped between, mainly for strength as it is a sea faring vessel.

[chris w]

Hi

 

We have a 25ft GRP cruiser that is hooked up to shore power whilst in the marina but uses a leisure battery whilst we are our cruising. We have a big inboard engine with a fairly hefty alternator so charging the batteries whilst out cruising isnt a problem. Our main power consumption is from the fridge, we use LED lighting, a low power consumption TV and every now and again the heating if it is cold enough to warrant it. We dont have a power problem and we only have 1 leisure battery on the go.

 

We have used our boat all this winter and even on the coldest nights when the marina/river/canal has frozen over we have just switched on the heating closed all of the curtains and watched TV in the warmth. We havent found the cold to be a problem. It can be a little chilly first thing in the morning but one of us braves it for a second to turn on the heating then we go back to bed for half an hour and when we get up the cabin is toasty again. Our boat isnt insulated but it does have vinyl in certain places to reduce the heat loss and double skinned construction with air trapped between, mainly for strength as it is a sea faring vessel.

The fridge will take around 50AH/24hrs so with light use of the other stuff let's say 70AH max/24hrs.

 

Questions:

 

How large is your single battery in AH's?

 

What's the nominal output of your alternator and the actual output?

 

What type of heating do you have?

 

Chris

[Gretzky]

We are pretty similar to Phylis we have a 28 foot GRP boat, over nighted on it throughout the winter, but we are also hooked to a 24/7 shore power supply. We have 2 110AH batteries connected to a 3 stage charger and a big engine and alternator too when we are out. The trick is though to use only the power you need, and use low power devices, LED lighting etc. I doubt you will ever get enough juice out of just 2 hours form the geny to charge you batteries properly, especially if while its on your sat playing on your xbox too!

[Naughty Cal]

The fridge will take around 50AH/24hrs so with light use of the other stuff let's say 70AH max/24hrs.

 

Questions:

 

How large is your single battery in AH's?

 

What's the nominal output of your alternator and the actual output?

 

What type of heating do you have?

 

Chris

 

Dont know the usage of the fridge just know its low consumption and very efficient. It doesnt kick in very often. Our battery is 110AH. The heating is a blown air diesel heater by Webasto again using very little diesel and very little power. Dont know the output of the alternator just know its big but given the size of the engine (170hp and loads of torque) it isnt an issue. We have found that we need to do at least 3 hours but really 4 hours daily cruising to top up our battery enough to keep us going whilst we are out of the marina.

[tnewson]

hmmm.. This is becoming more of a minefield...

 

My only problem is that im not sure on how the other islanders will feel if i run my own generator everyday...

 

With the maintenance batteries, what do you top them up with? Do you have to regularly check them with a hydrometer and litmus paper?

 

 

Do generators use alot of fuel? like if i were to run it 4 hours a day on average how much would that cost per run? Are generators mainly 2 stroke aswell?

 

 

thanks alot for the replys.. i cant seem to find any information thats this usefull anywhere else on the net..

 

 

Regards

[Naughty Cal]

What engine have you got? Can you not run that for a couple of hours as well as using the genny?

 

We just look at our batteries (starter and leisure) every now and then just to check the fluid levels. In the seven months we have had the boat we have not had to top them up or do anything other than check them.

[chris w]

hmmm.. This is becoming more of a minefield...

 

With the maintenance batteries, what do you top them up with? Do you have to regularly check them with a hydrometer and litmus paper?

Just simply check the water level by sight and top up with distilled water if necessary. I charge my battery bank with a large charger and an alternator controller and they never seem to need water.

 

Do generators use alot of fuel? like if i were to run it 4 hours a day on average how much would that cost per run? Are generators mainly 2 stroke aswell?

 

Regards

You will need a generator AND a multistage charger AND you will need to run it for more than 4 hours if you have used the batteries.

 

In general 2-strokes are cheap (£300) and very noisy. 4-strokes are very quiet but more expensive (Honda EU20i @ around £850).

 

Also, having petrol on board can be very dangerous as compared to diesel because the slightest spark could end in disaster owing to petrol fumes accumulating in your bilges.

 

Chris

[Naughty Cal]

Bilge blowers and engine bay blowers help eliminate that risk. We have them fitted even though we dont have any petrol on board. Run them for a few minutes before firing up the engine.

[tnewson]

Ah right,

 

thanks again for all the advice, reakon im gonna get 2 lorry batteries (170amp) run them parallel and i reakon ill buy a cheap 2stroke generator to run at the same time as the main generator to try and keep the riverside as quiet as possible! I've realised that im only going know how much electricity ill really need as soon as i move in!

 

My only other question is, Why do people say that its a bad idea to have a wood burner on a cruiser?

 

 

Cheers!

[Naughty Cal]

Ah right,

 

thanks again for all the advice, reakon im gonna get 2 lorry batteries (170amp) run them parallel and i reakon ill buy a cheap 2stroke generator to run at the same time as the main generator to try and keep the riverside as quiet as possible! I've realised that im only going know how much electricity ill really need as soon as i move in!

 

My only other question is, Why do people say that its a bad idea to have a wood burner on a cruiser?

 

 

Cheers!

 

GRP is flammable!!!!!!!!!!!!!!!!!

 

You need proper leisure batteries though.

[tnewson]

What does GRP stand for?

 

Why do they have to be proper leasure batteries?

[Naughty Cal]

Grp is fibreglass/tupperware or whatever else you want to call it. Plastic boats dont take too well to fire they tend to melt. So fitting a solid fule stove is a silly mistake. It can be done but strikes me as dangerous.

 

Leisure batteries are designed to be discharged more than normal vehicle batteries. Im sure the electrical experts can explain this in more detail, but vehicle batteries wont take the abuse of being constantly drained and then recharged.

[RLWP]

What does GRP stand for?

 

Why do they have to be proper leasure batteries?

 

Glass Reinforced Plastic GRP

 

The glass bit is fine, the plastic bit burns.

 

Richard

[mayalld]

Leisure batteries are designed to be discharged more than normal vehicle batteries. Im sure the electrical experts can explain this in more detail, but vehicle batteries wont take the abuse of being constantly drained and then recharged.

 

Oh dear, oh dear.

 

Could I interest you in buying a bridge?

 

Leisure batteries are bog standard automotive batteries with a handle on top, and a factor of two on the price.

[Naughty Cal]

A car battery is designed to give out a large amount of power in a short space of time (starting the car) and then being quickly recharged. A leisure battery on the other hand is designed to store power and release it over a much longer period of time. Undoubtedly you can use a car battery but it is unlikely to work very well in the long term.

[RLWP]

A car battery is designed to give out a large amount of power in a short space of time (starting the car) and then being quickly recharged. A leisure battery on the other hand is designed to store power and release it over a much longer period of time. Undoubtedly you can use a car battery but it is unlikely to work very well in the long term.

 

In theory, yes. In practice they are actually the same thing - same internal construction. The automotive market is huge, the leisure market tiny and price sensitive. Rather than make low-volume expensive leisure batteries that no-one will pay for, people make car batteries cheaply, put a leisure sticker on them with a bit of a mark-up and everyone is happy.

 

Richard

 

Gibbo will be along soon...

[mayalld]

A car battery is designed to give out a large amount of power in a short space of time (starting the car) and then being quickly recharged. A leisure battery on the other hand is designed to store power and release it over a much longer period of time. Undoubtedly you can use a car battery but it is unlikely to work very well in the long term.

 

No, a leisure battery is designed externally to convince the gullible that it is somehow different to a car battery.