Steps to improve the power situation on our boat

[Wild Is The Wind]

After struggling through many threads on this subject, I would really appreciate some simple advice on what to do next...

 

We don’t use shorepower, and our current batteries have lasted 12 months still running LED lights/pumps/electric flush toilet/12v mobile phone charger (and while the engine runs charging laptop daily, microwave 2-3 times a week, hairdryer/travel iron 3 times a week). The washing machine will not run anymore. The engine charges the batteries (4 x 110ah + starter) for 2 hours every night / 2 x 2 hours Saturday, Sunday and days off work. The red (low power) light now shows on the inverter (Victron Multiplus 3000w) within 10 minutes of the engine being turned off which even I know is not good!

 

I don’t (and may never) understand how to do a proper power audit, but we plan to get a 12v charger for the laptop, lose the microwave, add a 12v fridge, do one or two washes a week and eventually add a 12v TV and music system.

 

I really want to learn in basic terms how to improve and look after things and I’m going to do an engine maintenance course soon, but I still have loads of questions about boat electrics

 

- I’ve just read on another thread that the batteries should be deep charged for 8 hours at the weekends – should I be doing this?

- Can anyone recommend what kind of new batteries we should buy and how much they will cost?

- What is the best way to manage the battery charging by running the engine as we do now?

- When we can afford it should we go for solar power or a generator first? And what are Travelpack generators – should we consider this?

- Any recommendations for sourcing solar / generators and the likely cost?

 

Apologies in advance for such a long post – any advice will be gratefully received and hopefully help us move forward

[Robbo]

You need to do a power audit and know what your putting in your batteries (engine alternators can range from 40amp to 170+amp).

 

Read this thread: http://www.canalworld.net/forums/index.php?showtopic=43603

 

This free ebook from Victron: http://www.victronenergy.com/orderbook/

 

This recommended book is a good purchase: Boatowner’s Mechanical and Electrical Manual

 

 

Batteries are not a source of power. If electric was water, batteries are rusty buckets with holes in that get larger the more you use em and in addition 50% of the water just disappears on filling the dam things. The source is the tap (in your case engine/alternator), so when using high consumption devices like hairdryers and microwaves it's best to have the tap running. You don't want to run the "tap" all the time so you need the buckets, filling those buckets may require a bigger "tap" to reduce your time filling buckets.

 

 

Recommended tips:

 

If your alternator is of low amperage forget about 12v fridges and laptop chargers, concentrate your efforts (and money) on better charging (new/additional alternator?).

 

Use only high consumption items (especially washing machine / hair dryer / microwave) when your running your engine.

 

Leisure batteries are only good for around 100 discharges to 50%, if your discharging anywhere near this say every other night, then they will last 6 months. Traction batteries are better (Trojan are a good name) - but read the links above for other types of batteries which may be more suitable for you.

 

Get some kind of battery monitor, like the Smartguage or Victron's BMV-60xS..

 

 

My ideal setup is for non shore power generation...

 

Built in AC diesel generator with water cooled exhaust cocooned for soundproofing.

Traction batteries.

Invertor/Charger Combi.

Solar panels.

Edited April 3, 2013 by Robbo

[mrsmelly]

After struggling through many threads on this subject, I would really appreciate some simple advice on what to do next...

 

We don’t use shorepower, and our current batteries have lasted 12 months still running LED lights/pumps/electric flush toilet/12v mobile phone charger (and while the engine runs charging laptop daily, microwave 2-3 times a week, hairdryer/travel iron 3 times a week). The washing machine will not run anymore. The engine charges the batteries (4 x 110ah + starter) for 2 hours every night / 2 x 2 hours Saturday, Sunday and days off work. The red (low power) light now shows on the inverter (Victron Multiplus 3000w) within 10 minutes of the engine being turned off which even I know is not good!

 

I don’t (and may never) understand how to do a proper power audit, but we plan to get a 12v charger for the laptop, lose the microwave, add a 12v fridge, do one or two washes a week and eventually add a 12v TV and music system.

 

I really want to learn in basic terms how to improve and look after things and I’m going to do an engine maintenance course soon, but I still have loads of questions about boat electrics

 

- I’ve just read on another thread that the batteries should be deep charged for 8 hours at the weekends – should I be doing this?

- Can anyone recommend what kind of new batteries we should buy and how much they will cost?

- What is the best way to manage the battery charging by running the engine as we do now?

- When we can afford it should we go for solar power or a generator first? And what are Travelpack generators – should we consider this?

- Any recommendations for sourcing solar / generators and the likely cost?

 

Apologies in advance for such a long post – any advice will be gratefully received and hopefully help us move forward

 

Where to start

 

There are many ways to look at this and many options. I would think that you are no where near charging the batteries to capacity if just doing a standard 2 hour charge each day. Do you have any gauges? If not you do need one, many are available there is the smart gauge but its information is very limited though it will tell you when ur batteries are charged and more importantly depleted or you can get gauges that monitor amps in/out voltage, how fast you are charging etc etc.

I think your batteries are knackered if you have mistreated them for a year.

Microwaves are for houses or sophisticated EXPENSIVE generating systems as are hair dryers and irons

Solar panels are a very good help but again depends how much you spend.

You dont need to change your fridge, mains fridges are fine if batteries are charged correctly.

You will get lots of advice some good some bad.

My opinion is based on 23 years full time liveaboard experience on several boats with many different electrical systems.

My usual advice on all matters boat is that it most certainly is not and should never be treated as a small house, its a boat.

If plugged in at a marina for instance then the leccy problem is lessened greatly and small house syndrome can be adopted

 

Tim

[RickH]

You need to do a power audit and know what your putting in your batteries (engine alternators can range from 40amp to 170+amp).

 

Read this thread: http://www.canalworld.net/forums/index.php?showtopic=43603

 

This free ebook from Victron: http://www.victronenergy.com/orderbook/

 

This recommended book is a good purchase: Boatowner’s Mechanical and Electrical Manual

 

 

Batteries are not a source of power. If electric was water, batteries are rusty buckets with holes in that get larger the more you use em and in addition 50% of the water just disappears on filling the dam things. The source is the tap (in your case engine/alternator), so when using high consumption devices like hairdryers and microwaves it's best to have the tap running. You don't want to run the "tap" all the time so you need the buckets, filling those buckets may require a bigger "tap" to reduce your time filling buckets.

 

 

Recommended tips:

 

If your alternator is of low amperage forget about 12v fridges and laptop chargers, concentrate your efforts (and money) on better charging (new/additional alternator?).

 

Use only high consumption items (especially washing machine / hair dryer / microwave) when your running your engine.

 

Leisure batteries are only good for around 100 discharges to 50%, if your discharging anywhere near this say every other night, then they will last 6 months. Traction batteries are better (Trojan are a good name) - but read the links above for other types of batteries which may be more suitable for you.

 

Get some kind of battery monitor, like the Smartguage or Victron's BMV-60xS..

 

 

My ideal setup is for non shore power generation...

 

Built in AC diesel generator with water cooled exhaust cocooned for soundproofing.

Traction batteries.

Invertor/Charger Combi.

Solar panels.

That all sounds like good advice , what about 6v batteries ? I'm doing a refit soon and part of this is a new power system

[Arthur Brown]

Strongly suggest that you learn how to do a basic power audit. It's really simple - list every item, list it's rated current, work out or guess it's average duty cycle, this gives you the amphours that you consume. Then work out where these are coming from.

 

Try to fit a smartgauge to read your battery capacity % and it's cycle depth.

 

Go for a cruise for ten hours -let the engine alternator put power into the batteries according to the regulated charge rate it makes.

 

Try to fit lots of solar! A 150w panel will meet your needs in high summer a bigger panel array will extent the period when they are of use.

[Robbo]

That all sounds like good advice , what about 6v batteries ? I'm doing a refit soon and part of this is a new power system

 

I'm looking at 6v Traction Trojan's, as 2v ones won't fit where my batteries go. I did look at AGM's but Traction is cheaper but you need to maintain them (add water basically!).

[Alan de Enfield]

Doing a power audit :

 

Everything electrical should have a label/plate/sticker on it showing watts, volts and maybe amps.

 

'Segregate' your 12 volt and 220 volt appliances

 

1) Take each of your 12V appliances /lights, etc and estimate the amount of time (hours per day) it will be in use.

2) Amps used will be watts divided by volts (example 24 watt light divided by 12 volts)= 2 amps.

3) Multiply amps by number of hours in use

 

Do this for each 12v appliance (dont forget intermittant things like water pumps, bilge pumps etc) add all the things together to get the total.

 

Now take all of your 220v appliances - you will be supplying the 220v via an inverter which has inbuilt inneficiencies and also uses somepower itself.

 

If you take the appliance wattage and divide by 10 that will give you an approximate draw on tour batteries taking into account the Inverter.

Example - Fridge at 185 watts at 220v will take approx 18.5 amps from your batteries. Guesstimate how often the fridge is actually running (25% of the time is probably on the pessimistic side)so 18 amps for (say) 6 hours per day will be 108 amps in a day.

 

Add together the 'daily amps' used for all the 12v appliances,add on all the 'daily amps'used for the 220v appliances and you get your total daily requirements.

 

Due to various electrickery 'problems' you will need to put back in more than you take out, so if for example your usage totals 250 amps then you would be advised to put 300 amps 'back in'

 

You may imagine that if you have a 100amp alternator you could replace this 300amps in 3 hours - unfortunately this is not true, without going into the reasons and battery charging technology) you will probably need nearer 6 hours to replace what you have used.

 

Add -so many posts in the 20 minutes it took me to think and one-finger type my post

Edited April 3, 2013 by Alan de Enfield

[Arthur Brown]

What alternator is fitted to your engine? You will not get more than it's rated power out so a high rating may help. Early automotive alternators were 35A max modern alternators can give as much as 175A. However as batteries tend to self regulate their charge current only a discharged battery will take the full current.

[David Mack]

You dont need to change your fridge, mains fridges are fine if batteries are charged correctly.

 

True, but if you do the power audit you may well find that the fridge is nearly half your total power use.

 

So if you can minimise user of the fridge - turn it off at night and in winter, minimise the duration the door is open etc. - you can significantly reduce your overall electricity generation and storage needs.

[Wild Is The Wind]

You need to do a power audit and know what your putting in your batteries (engine alternators can range from 40amp to 170+amp).

 

Read this thread: http://www.canalworld.net/forums/index.php?showtopic=43603

 

This free ebook from Victron: http://www.victronenergy.com/orderbook/

 

This recommended book is a good purchase: Boatowner’s Mechanical and Electrical Manual

 

 

Batteries are not a source of power. If electric was water, batteries are rusty buckets with holes in that get larger the more you use em and in addition 50% of the water just disappears on filling the dam things. The source is the tap (in your case engine/alternator), so when using high consumption devices like hairdryers and microwaves it's best to have the tap running. You don't want to run the "tap" all the time so you need the buckets, filling those buckets may require a bigger "tap" to reduce your time filling buckets.

 

 

Recommended tips:

 

If your alternator is of low amperage forget about 12v fridges and laptop chargers, concentrate your efforts (and money) on better charging (new/additional alternator?).

 

Use only high consumption items (especially washing machine / hair dryer / microwave) when your running your engine.

 

Leisure batteries are only good for around 100 discharges to 50%, if your discharging anywhere near this say every other night, then they will last 6 months. Traction batteries are better (Trojan are a good name) - but read the links above for other types of batteries which may be more suitable for you.

 

Get some kind of battery monitor, like the Smartguage or Victron's BMV-60xS..

 

 

My ideal setup is for non shore power generation...

 

Built in AC diesel generator with water cooled exhaust cocooned for soundproofing.

Traction batteries.

Invertor/Charger Combi.

Solar panels.

 

Thanks for your quick reply and the tips!

 

The reading links are great and I have tried them (and will continue looking) but they are a bit too complicated - loved the bucket and water analogy though lol

 

I will work on getting a power audit done and finding out the size of the alternator as the next steps (hopefully something will be written on the alternator - i've never known what type it is, just that there is a seperate one for charging the starter battery).

 

Then from reading these posts I need to

 

- replace batteries and possibly alternator (based on power audit)

- fit a smartguage

- be clear about the charging regime

- look at fitting solar panels and a controller (possibly a system I can add to when funds allow)

 

I think the in-built generator you mention will be way out of my price range.

 

Where to start

 

There are many ways to look at this and many options. I would think that you are no where near charging the batteries to capacity if just doing a standard 2 hour charge each day. Do you have any gauges? If not you do need one, many are available there is the smart gauge but its information is very limited though it will tell you when ur batteries are charged and more importantly depleted or you can get gauges that monitor amps in/out voltage, how fast you are charging etc etc.

I think your batteries are knackered if you have mistreated them for a year.

Microwaves are for houses or sophisticated EXPENSIVE generating systems as are hair dryers and irons

Solar panels are a very good help but again depends how much you spend.

You dont need to change your fridge, mains fridges are fine if batteries are charged correctly.

You will get lots of advice some good some bad.

My opinion is based on 23 years full time liveaboard experience on several boats with many different electrical systems.

My usual advice on all matters boat is that it most certainly is not and should never be treated as a small house, its a boat.

If plugged in at a marina for instance then the leccy problem is lessened greatly and small house syndrome can be adopted

 

Tim

[mrsmelly]

True, but if you do the power audit you may well find that the fridge is nearly half your total power use.

 

So if you can minimise user of the fridge - turn it off at night and in winter, minimise the duration the door is open etc. - you can significantly reduce your overall electricity generation and storage needs.

 

I would agree with the fact that the fridge wether 12 or mains is the biggest user of leccy on board. What I always feel is somewhat silly is turning the fridge off at night. During the night the door is never opened so it will cut in very infrequently during this time and using far less power than during the day. The fridge will start the day at the correct temp without having to run longer to bring the temp down again all beit not long if been closed all nite. In my not inconsiderable years as a liveaboard I have never turned the fridge off at night and never suffered flat batteries because of this.

 

Tim

[Wild Is The Wind]

We never intended to treat the boat as a small house and were expecting to live with less applicances, etc. However the boat builder encouraged us to use these things as he said we had the inverter - the problem was we took this advice on face value with little knowledge on how to charge the batteries effectively.

 

We have a gauge that we were told should not fall below 12.4 and we should attempt to charge above 14 - this isn't enough information so I guess we need a Smartguage to replace this.

 

We charge the batteries with the RPM gauge on 10 or just below - 12-13 if microwave is used.

 

Doing a power audit :

 

Everything electrical should have a label/plate/sticker on it showing watts, volts and maybe amps.

 

'Segregate' your 12 volt and 220 volt appliances

 

1) Take each of your 12V appliances /lights, etc and estimate the amount of time (hours per day) it will be in use.

2) Amps used will be watts divided by volts (example 24 watt light divided by 12 volts)= 2 amps.

3) Multiply amps by number of hours in use

 

Do this for each 12v appliance (dont forget intermittant things like water pumps, bilge pumps etc) add all the things together to get the total.

 

Now take all of your 220v appliances - you will be supplying the 220v via an inverter which has inbuilt inneficiencies and also uses somepower itself.

 

If you take the appliance wattage and divide by 10 that will give you an approximate draw on tour batteries taking into account the Inverter.

Example - Fridge at 185 watts at 220v will take approx 18.5 amps from your batteries. Guesstimate how often the fridge is actually running (25% of the time is probably on the pessimistic side)so 18 amps for (say) 6 hours per day will be 108 amps in a day.

 

Add together the 'daily amps' used for all the 12v appliances,add on all the 'daily amps'used for the 220v appliances and you get your total daily requirements.

 

Due to various electrickery 'problems' you will need to put back in more than you take out, so if for example your usage totals 250 amps then you would be advised to put 300 amps 'back in'

 

You may imagine that if you have a 100amp alternator you could replace this 300amps in 3 hours - unfortunately this is not true, without going into the reasons and battery charging technology) you will probably need nearer 6 hours to replace what you have used.

 

Add -so many posts in the 20 minutes it took me to think and one-finger type my post

 

This is really helpful thank you, I will work on this.

 

What alternator is fitted to your engine? You will not get more than it's rated power out so a high rating may help. Early automotive alternators were 35A max modern alternators can give as much as 175A. However as batteries tend to self regulate their charge current only a discharged battery will take the full current.

 

Its a newly built boat so would have thought it was a fairly good one, but I will check.

[Tony Brooks]

Thanks for your quick reply and the tips!

 

The reading links are great and I have tried them (and will continue looking) but they are a bit too complicated - loved the bucket and water analogy though lol

 

I will work on getting a power audit done and finding out the size of the alternator as the next steps (hopefully something will be written on the alternator - i've never known what type it is, just that there is a seperate one for charging the starter battery).

 

Then from reading these posts I need to

 

- replace batteries and possibly alternator (based on power audit)

- fit a smartguage

- be clear about the charging regime

- look at fitting solar panels and a controller (possibly a system I can add to when funds allow)

 

I think the in-built generator you mention will be way out of my price range.

 

 

 

You also need to do some charging calculations as well - a 70 amp alternator probably only averages about 35 amps over about 3 hours or so, then the average starts to reduce. Fitting a larger alternator is unlikely to make up for insufficient running time. This is why solar and shoreline charging that goes on for hours at low values is good.

 

Have a look at my electrical course notes. There are worked examples in there. My link

 

PS look at the energy audit in the maintenance notes - its probably better.

Edited April 3, 2013 by Tony Brooks

[mrsmelly]

We never intended to treat the boat as a small house and were expecting to live with less applicances, etc. However the boat builder encouraged us to use these things as he said we had the inverter - the problem was we took this advice on face value with little knowledge on how to charge the batteries effectively.

 

 

 

And heirin often lies the problem. Most people with little experience will obviously listen to their chosen boatbuilders advice but this is fraught with danger for two main reasons.

One reason is that it is in the interest of the builder to fit as much stuff as he can as its all more profit and the other reason is that very very few boatbuilders live on or have ever lived on a boat so have no concept of reality on whats needed on living on a boat.

 

Tim

[Ally]

I really would encourage you to try & lay out for some solar. It will soon pay for itself in diesel savings. You can also set up the controller to stop you allowing your batteries to get too low. You'll be surprised how much solar will help, and keep you batteries in much better condition.

If you can, lose as much 230v as possible, ideally all of it.

we only use 12v now, have two 135 solar panels, are unable to charge off our alternator, no landline, used our little genny for a total of 6 hours between Sept-March. We live aboard also. We have already been hitting 100% charge over the last 3 weeks, and 'wasting' power. Over winter we never let the batteries (4x125 agm's) go below 65%. Fridge off over winter but on 24/7 since the beginning of March.

solar.....

 

Edit to add, having read Tim's post....liveaboard boat builder!

Edited April 3, 2013 by Ally

[Wild Is The Wind]

You also need to do some charging calculations as well - a 70 amp alternator probably only averages about 35 amps over about 3 hours or so, then the average starts to reduce. Fitting a larger alternator is unlikely to make up for insufficient running time. This is why solar and shoreline charging that goes on for hours at low values is good.

 

Have a look at my electrical course notes. There are worked examples in there. My link

 

PS look at the energy audit in the maintenance notes - its probably better.

 

 

Thanks Tony, I will

 

I really would encourage you to try & lay out for some solar. It will soon pay for itself in diesel savings. You can also set up the controller to stop you allowing your batteries to get too low. You'll be surprised how much solar will help, and keep you batteries in much better condition.

If you can, lose as much 230v as possible, ideally all of it.

we only use 12v now, have two 135 solar panels, are unable to charge off our alternator, no landline, used our little genny for a total of 6 hours between Sept-March. We live aboard also. We have already been hitting 100% charge over the last 3 weeks, and 'wasting' power. Over winter we never let the batteries (4x125 agm's) go below 65%. Fridge off over winter but on 24/7 since the beginning of March.

solar.....

 

Edit to add, having read Tim's post....liveaboard boat builder!

 

 

This is really useful to know and is sort of what I was thinking, and i've accidently given you a greenie too lol

[sueb]

I have a gas fridge and have been running the engine once a fortnight for a couple of hours. I live on the boat with no shore power, but we built our boat to be able to do this

[mrsmelly]

I have a gas fridge and have been running the engine once a fortnight for a couple of hours. I live on the boat with no shore power, but we built our boat to be able to do this

 

Once again sue does a short post with lots of sense. Gas fridges are indeed the best option by miles and miles. We had one on our first boat for 5 years, great performance just change the gas bottle once a monthish and no batteries to constantly charge.

 

Tim

[Robbo]

Once again sue does a short post with lots of sense. Gas fridges are indeed the best option by miles and miles. We had one on our first boat for 5 years, great performance just change the gas bottle once a monthish and no batteries to constantly charge.

 

Tim

 

Shame they don't make a room sealed one these days.

[mrsmelly]

Shame they don't make a room sealed one these days.

 

You are right. Mind you I have not heard of hundreds of deaths relating to the good old fashioned ones I and thousands of others have used over the years. Ocasional maintenance and sensible ventilation is all thats needed.

 

Tim

[smileypete]

I really want to learn in basic terms how to improve and look after things and I’m going to do an engine maintenance course soon, but I still have loads of questions about boat electrics

OK some quick answers...

 

- I’ve just read on another thread that the batteries should be deep charged for 8 hours at the weekends – should I be doing this?

 

They need a longer charge at least once a week. How long? well an ammeter can tell best when they're fully charged, see below....

 

- Can anyone recommend what kind of new batteries we should buy and how much they will cost?

 

In your situation you're probably best off sticking with reasonably decent non sealed (open) leisure batteries. Read all the handling precautions on http://www.batteryfaq.org, then when they arrive make a note of where they're topped up to, better still get the supplier to show you how. Then from time to time check them after charging and keep topped up to the same level with deionised water.

 

- What is the best way to manage the battery charging by running the engine as we do now?

 

Best way is with an ammeter or a battery monitor that can read amps. Once a week charge try to charge them til the charge current tails off below a certain level, with your size batt bank just below 10 amps. The rest of the week a much shorter charge should suffice.

 

For telling when it's time to charge the easiest way is with a Smartgauge, though it costs £160. Some people use other battery monitors like a Nasa BM1/2 that do need careful setting up, others get by OK with a reasonably decent voltmeter that only costs £10-20.

 

- When we can afford it should we go for solar power or a generator first? And what are Travelpack generators – should we consider this?

- Any recommendations for sourcing solar / generators and the likely cost?

 

Makes a lot of sense, Ebay is a good source of panels and for a solar controller, quite a few people buy a 'Tracer/EP solar MPPT'. The solar thing might deserve another thread to itself though.

 

Apologies in advance for such a long post – any advice will be gratefully received and hopefully help us move forward

 

Something useful to have around is a battery hydrometer, from the likes of Halfords or a good motor parts place, they can help check the batts are OK or not. The better hydrometers have a glass float inside a bigger glass tube, again read the precautions on http://www.batteryfaq.org, you could practise on your existing batts if they're not sealed ones to see how cream crackered they are.

 

cheers, Pete.

~smpt~

Edited April 3, 2013 by smileypete

[Robbo]

You are right. Mind you I have not heard of hundreds of deaths relating to the good old fashioned ones I and thousands of others have used over the years. Ocasional maintenance and sensible ventilation is all thats needed.

 

That's the main problem, people don't. If you didn't maintain a room sealed one it isn't dangerous if the flue gets blocked.

[matty40s]

My battery bank is over 5 years old now, 6 out of the 7 in the bank purchased second hand from good old Vince's ex windscreen replacement van source.

I don't have a smartguage(but recommend them for folks that need to know what the bank is doing!).

 

I have not looked after the bank, in fact , severely abused it in some winters, coming home from work and running the enjun for 30 minutes at the same time as sticking the eberspacher on for the shower hot water.

I introduced a single 100W solar panel 4 years ago (£350) and then an additional 200W with MPPT (£230) early last year.

I am currently playing with settings and voltages attempting to prolong the bank life even further.

There isn't any serious science, I am just playing with equalisation and floatplus (!!)

 

I can still charge lappy and mobile whenever I want, my lappy has been on for most of today as I am studying, watch DVD's in my flatscreen TV whenever I want, and I can run power tools when the sun is shining.

I have occasionally been known to iron a shirt!!

Solar is by far the most sensible investment for ANY liveaboard. It protects your engine, provides gentle charging from early hours March to Oct, and in Winter provides some power too.

 

It is 10.06 pm and my bank is still showing 12.6V - with lappy charging through 240V inverter.

[sueb]

Shame they don't make a room sealed one these days.

Gas cookers aren't room sealed

[Robbo]

Gas cookers aren't room sealed

 

There not on 24/7 and don't have a flue that can get blocked.