Forums, Electrical Systems, Navigation and Safety equipment, Battery xcharging - Mooring

gregcope at 20/02/2011 08:51:08
Hi All,

I am thinking about battery charging. I plan to keep my CO32 on a mooring, so a shore powered battery charger is not much help. Although I like wind turbines, I hate the noise some make. So a default becomes solar panels. I appreciate that in the UK the solar panel efficiency is a bit rubbish!

We presently have a twin 75Ah battery bank. I doubt this will increase by much. Our electrical load is quite low as we are not planning any night sailing, and if we do I would look to fit LED lights. No plans for Radar either. Present usage would be lighting (plan to switch some key bulbs to LED), engine starting, bit of Depth/GPS.

We presently do not have a fridge, so this is the only electric hog I can foresee.

Any ideas, suggested locations, and especially pictures?

George Isted at 21/02/2011 14:45:12
Hi Greg,
Like yourself, I keep my boat on a mooring without the ability to plug in so have to keep an eye on the batteries; I would make the following comments and suggestions. The first one being that the boat has been in it’s current configuration for some time and if you are going to make improvements to the power usage by adding LED bulbs etc then your power requirement is going to go down not up therefore there is a pretty good reason for changing nothing.

gregcope at 21/02/2011 20:13:17
Thanks George.

On the aesthetics front I was considering a semi-flexible pannel, that should only be obvious from the top, and neither a rigid pannel with associated frame, or a gantry.

Interesting that you run the fridge on your present setup which is similar to mine, including the mooring.

Do you have a shore battery charger, or just rely on the engine alternator+charge regulator?

Wisdish at 21/02/2011 21:11:09
We have used our Co32 extensively each summer, with standard bulbs for lighting, and the fridge Geoge refers to (I will complete the technical paper shortly – honest) without any major problems with battery capacity. We have found that the charging from normal engine use is sufficient. However we do have a somewhat larger domestic battery bank (3 × 105 Ah batteries).

We have just bought a SmartGauge battery monitor (available from Maplin), which we have heard very good reports of; this is slightly pricier than the NASA BM1, but has the advantage of being significantly more sophisticated in the way it calculates battery capacity, and does not require a current shunt. This should give us more accurate information on how much battery capacity we are actually using and we will soon find out whether we really need all those domestic batteries!

Mark

George Isted at 21/02/2011 21:21:09
Hi Greg,
Yes I do have a shore power battery charger, it is a Stirling multi-stage type that you can leave on all the time then plugged in, to be fair it doesn’t get a huge amount of use but does the job well.

gregcope at 21/02/2011 21:41:25
Mark,

A tech fridge guide would be very handy!

George,

Like Alderney and trying to persuade my partner that the young family would love the beaches, just need to get used to sailing!

Hatch Garage was an idea, as either side of that gets shaded by lines going aft to the cockpit, and liable to being trodden on, where as that is more isolated, although shaded by the boom – but I supposed that would happen to either location.

Just need to look at Spray hoods getting in the way.

Either a Shore powered battery charger or a pannel would solve my present winter job of removing the batteries to charge them. Interesting job as they are not light!

nardus at 22/02/2011 08:05:32
I`ve seen some nice examples on top of a sprayhood. If nicely done with a flexible panel its `s only visible from above. I`ve taken measurements and there would ben enough place to mount an 600×900mm solarpanel.

Mark Hillmann at 22/02/2011 22:05:23
On Milly Brown we use a couple of small semi-flexible solar panels forward of the spray hood and mounted above all the ropes leading back to the stoppers. Stepping on the ropes was less fun than stepping on the panels. With a regulator they keep the batteries fully charged for your return to the boat.
They run:

Lighting: All LED except the tricolour, I failed to rotate the bulb mounting by 180 degrees for the led bulb and left the old one in.
Instruments including AIS radar, which all take little current,
Chartplotter: It is the illumination on ours that takes the current, we turn down the brightness unless using it.
Fridge: With the thermostat turned down to cool it while the engine is running, it seems OK ticking over at a higher temperature all the rest of the time.

Our digital voltmeter / ammeter shows the panels will not cope with:
Laptop – the more modern ones seem to use more.
Heating (starting and stopping it uses a heavy current), or the
VHF/navtex: I was surprised how greedy that is. The handheld is more use going in and out of harbour short handed, which is when the radio is normally used. It gets forecasts OK and lives on, needing infrequent charging. DSC has made channel 16 a lonely place in the Irish Sea and Scottish west coast.

On night passages our single 110 amp hr domestic battery may need one boost if we have not been careful. On longer passages we have a towed charger which allows extended use of the laptop, VHF and heating, unless the wind drops.

Mark Hillmann

doug at 23/02/2011 20:42:00
Like you I have a fairly feeble battery set up but limited requirements for power.
My Small Aerogen 25 has been superb. It is spinning as we speak and has been for the last 15 years, and probably 10 years before that. The only things that I have replaced are two sets of bearings costing a few pounds. In all normal wind speeds it is silent.
I have it mounted on a short pole so it operates in the slot between the deck and the boom. This means it is also more in tune with the scale of the boat. It would be a danger underway so it is tied off, but for charging up between trips, on my swinging mooring, I would not be without it. I never seem to run out of juice even though I run my engine to the minimum.
Solar panels are great but finding a bright spot can be a problem. Perhaps a portable unit on the foredeck?

Nyaminyami at 17/03/2011 22:17:16
Hi George
This is a very helpful post. I’m looking at optimising our battery charging as we too are on a river mooring and can only use a charger if we visit a marina, which is not very often. Our current set up is x2 75amp hour batts for engine and domestic use. I’m thinking about beefing up the domestic battery, but will stick with 75amps for the engine starter. I’m not too keen on adding another alternator, so am interested in what you’ve done. We’ve got a Yanmar 2GM with the standard 50amp output alternator. I’ve looked up the Stirling website: did you use the Digital Advanced Aternator Regulator? This seems a lot less than going the additional alternator route. I presume you had to add the field control regulator wire[this looks fun]and did you also install a battery isolator?

Many thanks for any advice

Alastair Pugh at 18/03/2011 09:09:18
I fitted the cheapest of the Stirling regulators to my 2GM with 35amp alternator last year. What a difference! Before, the batteries (2×110Ah) never seemed to be fully charged, even after days of motoring, whereas with the regulator it takes very little to keep them in the nearly 13v (voltmeter doesn’t allow better resolution) range. I too am on a swinging mooring and have an Aerogen lurking in my garage waiting to be fitted but after last year’s success it looks like it’s in there for another year. 12 hour night sails with radio, instruments, ST2000, LED tricolour, Navtex, computer (screen off mostly) take one battery down to the instrument glitch stage but an hour or so of engine puts it all back.
The fitting instructions are clear enough to take the worry out of adding the extra wire to the alternator and it gives you a chance to see how much brushes are left!

Nyaminyami at 18/03/2011 10:23:54
Thanks Alastair: very helpful
What isolator did you use?

George Isted at 18/03/2011 12:33:43

Hi Simon,
To answer your question I would need to head down to the boat and check but from memory it is the Digital Advanced Alternator Regulator, it was fitted by the previous owner and works really well. You are correct that there is a little wiring to do on the Alternator to bypass the standard regulator. I do not have a battery isolator but a standard 1,2,both,off battery switch that is generally set to both. The batteries are 2 x Numax 110Amp/hr, they are called sealed batteries but it only takes a second to open up the top and check the electrolyte level – this is very important if you care fitting a separate high-power regulator.

Nyaminyami at 18/03/2011 15:03:01
Thanks George: super reply. Will get reading.

Wisdish at 18/03/2011 21:21:54
Another website that is worth a look if you want to get into the technicalities is www.smartgauge.co.uk. They appear to have moved on the technology of charging to another level by tying their charger (their Smartbank) into a monitoring system (their SmartGauge) that more accurately assesses the charge level of the batteries using Peukerts Law. The more accurately you can monitor the state of charge of the batteries the more accurately you can charge them.

We are fitting the SmartGauge this refit, but budgetary limitations mean that we will stick with our Mastervolt three stage charger for present.

Note that Smartgauge has now been taken over by Merlin Power, but the original website has better technical info.

Alastair Pugh at 19/03/2011 09:46:24
I’m another without an isolator – just switches. Both for starting and one only when sailing. I have a VSR on my wish list but it’s pretty far down.

gregcope at 19/03/2011 18:26:22
Little question.

People with Advanced Regulators, do you mount them in the engine Machine space?

Alastair Pugh at 19/03/2011 22:29:53
Little answer.

Yes.

gregcope at 20/03/2011 09:32:45
Thanks Alistair.

Is that where people put battery chargers too?

Wisdish at 20/03/2011 20:03:35
Our battery charger sits under the chart table mounted vertically on the bulkhead. It’s clear of your knees.

Alastair Pugh at 20/03/2011 20:09:01
Mine is on the pilot berth side of the longitudinal engine bulkhead. A pretty stupid place, prone to being banged by anyone athletic enough to fit in the berth, but I’ve never got round to moving it somewhere more sensible.

gregcope at 20/03/2011 20:14:29
Interesting…

Alastair, I agree the pilot berth one seems a little in the way.

Wisdish, not sure we could fit one there, as I am sure you would hit it with your knees? Do you have draws under the chart table (facing the middle)?

I am wondering what is inside of electrical pannel as it would seem there is lots of space behind/around it that is encased by the panelling.

Wisdish at 20/03/2011 20:24:06
Ours is a Mastervolt charger very approx 250×200×50mm mounted towards the outboard of the chart table which is as you describe.

When considering a mounting location note that many of these chargers have internal fans as they generate a fair amount of heat, so you need to make sure you have sufficient airflow/airspace around them to prevent overheating.

Mark

George Isted at 21/03/2011 12:07:21
On Concerto the Stirling alternator regulator is fitted in the engine space near the alternator. The shorepower charger is fitted high-up inside the quarter-berth on the outside of the engine space. I tend to sleep in there when we have the full racing crew onboard and it has not caused a problem to me although I do tent to switch it off when sleeping as the fan would probably keep me awake.

Tiptoe at 14/04/2011 18:44:54
Hi
Over the last seven seasons we have slowly upgraded our electrics as we too live on a mooring.

To date we have a battery bank of two; one for engine starting only and one 110AH domestic battery. The latter is connected to a NASA BM1 Battery Monitor and a few years back we fitted an 80AMP Stirling Alternator to Battery Charger. The advantage of this is that it requires no opening up alternators and soldering field wires. The disadvantage include that it is more expensive to purchase and we spent a fair amount on cables to install it. Ee mounted this behind the drawers under the chart table. On the rare occasion we need to check the indication lights we just whip out the top drawer.

This setup has coped pretty well though our coolbox style fridge has been responsible for using most the AH, having said that being in Scotland its performance has improved! A couple of years ago we added a Forgen 500, which enabled us to use the Raymarine Tiller Pilot for virtually 24hrs on a decent fetch across to Ireland before the battery had enough. This addition has been definitely worthwhile but it is little more than a trickle charger. This winter I’ve added a 32W Solar Trader Flexible Solar Panel which will be laid over the Sprayhood.

I believe that none of the above have detracted from the appearance of Tiptoe, as perhaps adding a Rutland 913 or solar panel gantry would however we don’t benefit from quite the increase that those would provide. Working in combination with LEDs etc they have made our life more independent.

Edited: Tiptoe on 2011-04-14 18:52:30

gregcope at 16/04/2011 17:01:46
Thanks tiptoe, interesting feedback and I had not thought of the behind the draws location.