Economizing a solution to flat batteries.

[Micha Cook]

Hello hello,

 

Needing some advice about finding a good, but affordable, solution to flat batteries.

Bluebell is a little 23' cruiser with a Honda outboard of 9.9 HP.

When we were only exploring and moving it on weekends for 5-6 hours a day, the batteries were doing really well, but now that we're back to work and more settled, moving only one day a week/fortnight, we've had problems with the batteries.

 

We have one startup and one leisure. It seems that the startup is too low, so we seem to be running of the leisure battery, which is not working very well (lights dropping intensity and flickering a couple of days after moving the boat). My SO and I are both out of the house from 7/8am to about 9pm, so we haven't been able to let it idle daily. We've tried to counteract it by using the batteries minimally, charging phones at work etc unless in an emergency, only using one light and candles/fairy lights, etc. We don't use any other 12v appliances, so mostly the batteries are powering the water pump and 1-2 LEDs for a couple of hours a day.

 

Anyhow, we've only just bought the boat so are really skint. We want to invest in solar panels, a mains charger, a traction battery, and a generator but dont have the 3odd grand to fund all those purchases at once.

 

What would you all suggest as a first purchase?

 

Considering the cost of a gennie, would solar panels (which are in our planned budget) serve the purpose of getting our batteries back to scratch and maintaining them?

 

Or do we need to invest in a gennie/panels/charger all at once? We've only just bought the boat and spend 2k kitting it out internally, and adding all of the above amounts to the cost of the boat (though I suppose we can take them with us when we leave) so if we can buy these things in stages that would help.

 

Also, we don't have a place to store the gennie unless we build a storage area onto the stern...

 

All of these are worries...

 

Someone suggested transporting the batteries to an on-land friend's house and charging them back up there, but that seems intrusive and difficult and we'd much rather have a long term solution that works.

 

Would be most grateful for any and all advice

 

Thank you,

Micha

[Naughty Cal]

I wouldnt bother with the traction battery until you have sorted your charging out. You will kill it just the same as an ordinary el cheapo wet cell battery.

 

Solar would seem the obvious place to start.

[zenataomm]

Are you using the electric start on your outboard?

If so, that alone will probably take half an hour of running to replace the power used in starting it.

[Arthur Brown]

Taking the batteries to a good friend's place and charging them will save their life if done once, BUT you need to have charging facilities on the boat after that.

 

Solar is the obvious choice, a ten watt panel will probably keep the starter battery full, Start the domestic panel array with more than that, say 100w for a start. This should stop the batteries being destroyed by sitting flat. The summer will yield a greater electrical harvest due to both light intensity and day length. For next winter you will need more panels and a generator based charging regime, but the first panels will buy you time to look around and buy carefully.

 

Outboard engines are notorious for having very small generators -ideal for a starter battery but not for a live aboard house battery.

[Paul C]

Solar would be the obvious first thing to add, as soon as its installed its generating electricity at £0 running costs. Get enough solar power and match it with economising on electricity usage in spring and autumn so you can go quite well into the autumn before running out. Then for next winter, look seriously into a generator.

 

PS Very worth doing a power audit too. And knowing which loads are coming out of which batteries, at all times

PPS If the outboard has a pull starter and you're limited in space, you could use both batteries as "domestic" and if they go flat, you can still pull start the motor. If not flat then use the electric starter.

[PaulG]

The first thing I would do is to hoik both batteries out, take them home and give them a good charge up.

I know this is probably not easy, but they will become damaged if you leave them discharged.

[Micha Cook]

Thank you all, good to know. We think we have enough dosh and roof space for 2 100W panels, fingers crossed anyway, the only clutter up there is a chilli plant hah.

Biggest doubt at the minute re: panels is whether to buy a kit or individual parts.

 

If anyone has time, anyone mind giving a nod about these?

 

http://www.hollybrookps.co.uk/pv_modules/100w-solar-panel-a-rated-monocrystalline.html

http://www.hollybrookps.co.uk/pv_modules/195w-solar-panel-a-rated-monocrystalline.html

If buying the kit separately, which of these panels?

http://www.amazon.co.uk/charging-battery-motorhome-campervan-off-grid/dp/B00BNJUBHY

http://www.hollybrookps.co.uk/canalboat-narrowboat-solar-kits/200w-canal-boat-solar-kit/action/null/

Or these kits?

Someone recently suggested this page as well, http://www.bimblesolar.com/solar but it's very bright and I'm finding it hard to sift through ahahah

Muchas gracias for all your help so far

[p6rob]

Get the solar sorted first. I'm in a similar position to you, out most days and only able to run the engine once or twice a week when not moving. I thought I was doing well not running the engine very often, but at two years old my three leisure batteries are not holding charge very well any more.

I've jerry rigged my solar panels until such time that I have spare cash and Matty is available to install them properly. Now I no longer need to worry about rushing back to keep things charged up. Wish I'd bought solar sooner, it makes life a lot easier.

 

If cash is an issue, get a decent controller with spare capacity and at least 200w of panels. You can always add more panels at a later date to increase charging capacity if necessary.

 

Rob

[Alan de Enfield]

The Honda 9.9 has a charger of only 6 amps which is an insignificant amount.

 

Outboard engines are not (designed) for charging a leisure battery as well as the starter battery,

Running the engine for 5 hours every day was giving you 30aH, this was obviously 'enough' for your needs but an 'odd hour' every few days is going to lead to destroying your batteries - if they have got to the stage that the lights go dim then it may be already too late to save them (in which case do not buy any more as they will be destroyed, and the money wasted.

 

Step 1 - Take the batteries off and give them a good 24 hour charge with a battery charger (ideally not a little Halfords 4 amp charger)

 

Step 2 - Buy a Generator AND a battery charger. Using the 12v output on a generator will not give you much more charge than your outboard. Get a reasonable sized charger (maybe 20 amp +) and run it off the genny.

 

Solar will contribute, but although the days are now getting longer, small panels are unlikely to give much immediate help

[stuart]

I'd recommend Bimble Solar, they often have good deals on second hand panels - which are much cheaper than you expect.

 

Two of these panels would give you 240W, plus an 20Amp MPPT charger like this (http://www.bimblesolar.com/offgrid/mppt/Tracer2215BN)

 

http://www.bimblesolar.com/solar/individual/kyocera120w

 

and apart from cable, would have a solar charging solution for £200.

Edited March 18, 2015 by stuart

[stuart]

 

Thank you all, good to know. We think we have enough dosh and roof space for 2 100W panels, fingers crossed anyway, the only clutter up there is a chilli plant hah.

Biggest doubt at the minute re: panels is whether to buy a kit or individual parts.

 

If anyone has time, anyone mind giving a nod about these?

 

http://www.hollybrookps.co.uk/pv_modules/100w-solar-panel-a-rated-monocrystalline.html

http://www.hollybrookps.co.uk/pv_modules/195w-solar-panel-a-rated-monocrystalline.html

If buying the kit separately, which of these panels?

http://www.amazon.co.uk/charging-battery-motorhome-campervan-off-grid/dp/B00BNJUBHY

http://www.hollybrookps.co.uk/canalboat-narrowboat-solar-kits/200w-canal-boat-solar-kit/action/null/

Or these kits?

Muchas gracias for all your help so far

 

Nothing wrong with what they are selling, but Bimble are better value for money. You will also want a MPPT charger, not the PWM one (these are cheaper and less performant)

[bizzard]

If you haven't already, you need either a battery changeover switch or a split charge relay so that the engine battery is kept charged up regardless of the state of charge of the cabin battery. This is important if you always want your engine to start. Once the engine battery is charged you switch the changeover switch to cabin battery so as not to drain the engines battery whilst using the interior lights and cabin facilities. A split charge relay does the same thing automatically. A small camper van split charge relay will cost about a fiver or a change over switch not much more.

[Arthur Brown]

You could probably use simply a small solar panel (5watts max) to keep the starter battery charged, using a small one just keeps up with self discharge losses but saves you the cost of a regulator. This doesn't gain house power but it does mean that the engine will always start. A simple PWM charger will regulate if if needed (maplin were selling some velleman ones for £10)

 

The domestic solar array needs more care. 100w may see you through the summer but get a bigger MPPT controller so that you can add another panel or two before winter. Solar is best if you have or can get a sunny mooring.

 

Remember that your starter battery should be protected against all other loads. If the starter is flat you have no engine, if the house battery is flat then you need the starter to work first time. The incorporated 6a charger is insignificant for the house battery unless you are cruising 10 hours plus per day.

 

Looking for a petrol/diesel/gas fuelled generator that will feed a charger is your next big plan preferably before winter.

 

AA battery powered LED lights are much safer than candles and tea lights

Edited March 18, 2015 by Arthur Brown

[Paul C]

 

 

Remember that your starter battery should be protected against all other loads. If the starter is flat you have no engine,

 

 

Before we all go much further, can the OP clarify if the engine has a recoil start?

[bizzard]

And a changeover switch or split charge relay.

[smileypete]

Cheap PWM controllers are a bit hit or miss sometimes, these are fairly decent (made by the same company that make the Tracer MPPTs):

 

http://www.ebay.co.uk/itm/EP-Solar-Landstar-20A-12-24V-Solar-Controller-inc-15-Hour-Light-Timer-Function-/281633531448

 

Add a couple of the above mentioned 120W panels from Bimble, for a cheap but reasonably decent system for about £165ish.

 

The panels from Bimble are so cheap that adding a £90 MPPT, very good though it is, will boost the output but probably not give more watts per £.

 

cheers, Pete.

~smpt~

Edited March 18, 2015 by smileypete

[Phil Ambrose]

I'm a little unsure if the OP is living on the boat, if so it does rather throw things in another direction.

Phil

[LEO]

Hi,

 

I use a portable 'back-up' power pack from Halfords (about £100), contains jump leads and a power out put point (Cigarette Lighter) PLUS a 350 watt inverter.

 

Will charge 'phones etc and can be easily transported for re-charging by a 12 volt source or a 240 volt input.

 

It also has a lead with a 'lighter point at each end for easy connection into your 12 volt system.

 

I have a 5 battery system on a nb, but still find it handy.

 

L

[FidoDido]

Solar is the way to go, as others have said. Small one for the starter batt, and more for domestic. For info, I have one 170w panel, and find it adequate for all months apart from dec, jan and feb, when I also run the engine a bit if it's been cloudy for a number of days. Therefore with your low power usage (I run a TV 3 or 4 hours a day) I'd think two of those Bimble 120w panels, coupled with their PWM controller would be the cheapest option. The bimble panels in question are 17v panels, so a PWM controller will likely give similar output than a MMPT. However, if you get solar panels with a voltage higher than 20 v (many are 36v) then the MMPT is a must, as it converts the extra voltage over 15v into amps. The PWM ones just discard the extra voltage. My 36v 170w panel for example gave a maximum of 2.7 A with a PWM, but gives up to 11A with the MMPT.

[James Owen]

A good set of solar panels will keep your batteries topped up but as has been suggested also, removing them and giving each a good charge on a dedicated charger will bring them back. The sooner the better.

Don't expect the solar panels once fitted to then recharge the batteries from flat, this could take some time and the longer you leave them uncharged.....

[blackrose]

I'm a little unsure if the OP is living on the boat, if so it does rather throw things in another direction.

Phil

The OP also mentioned a mains charger. Does the boat have access to shore power?

 

If so that's going to be the best option while moored up over winters.

[Alan de Enfield]

The OP also mentioned a mains charger. Does the boat have access to shore power?

 

If so that's going to be the best option while moored up over winters.

 

Are you meaning this part ?

 

Someone suggested transporting the batteries to an on-land friend's house and charging them back up there

 

My reading of the OP is that they are liveaboards, have no electricity supply, and are possibly trying to CC (location London) (hence moving only every 14 days)

 

There is no evidence of a 'land based' property as they have to take the phones to work to charge them.

 

They have an immediate problem and need a solution 'today' hence my suggestion of a generator which they could nip-out to machine mart and source, Purchasing Solar panels will take a few days to arrive and maybe a few more days to get them wired in (they are both at work until 9pm)

 

Not only are they going to need to buy some 'charging equipment' but as every day goes by it is more likely that the batteries will need replacing.

 

Edit - thinking about it, if they are at work from 7am to 9pm they cannot use a generator, Dilemma !!!

Edited March 19, 2015 by Alan de Enfield

[MtB]

 

Edit - thinking about it, if they are at work from 7am to 9pm they cannot use a generator, Dilemma !!!

 

Dilemma indeed.

 

I took the OP to be living aboard too, but they appear to be living frugally (power wise) as they say two days' cruising each weekend provides enough charge to last them a whole week, using just the 6amp outboard charger. But now they only cruise one day a week so the amount of engine charging that the solar needs to replace is quite small.

 

The days are getting longer and the light stronger, and I think a single 100w panel and cheap pwm controller will get them out of the hole they are in now. They only want to run a few LEDs and a water pump. The battery has been demonstrated to be big enough, it just needs some more charging now they are cruising less.

 

Later, when more funds are available I suggest a second 100w panel if there is room on the roof and chucking (or selling) the cheap pwm and getting a MPPT.

 

One final thought, if the OP runs a car, lugging the battery to the car and charge it via the ciggy lighter on the next long journey...

[Arthur Brown]

OP; Can you get to a marina or boat yard on one of your cruises? Can you take the batteries inside there to be charged -eg overnight? Can you get to somewhere where you can pay for and use a shoreline to charge the batteries?

Added; is there an auto electrician near your mooring who would charge your batteries for you?

 

Tell us where you are, it's far easier to find help if we know where you need help, London is a big place I live in London but other parts of London are two hours drive away or more by public transport.

Edited March 19, 2015 by Arthur Brown

[Alan de Enfield]

 

Dilemma indeed.

 

I took the OP to be living aboard too, but they appear to be living frugally...............................

 

To be honest, that would be more my idea of purgatory than 'frugal', no lights, no computer, no TV, cannot even read a book or (or re-charge) my Kindle.

On a 23 foot cruiser there is probably no SF stove and it will (at best) rely on blown air eberspacher heating (more electricity), or possibly leaving the gas-rings on. Hot water for a shower ?

 

Owning a boat does not have to mean 'living in a cold dark cave'.