How much 'free' electricity in Med?

[syvictoria]

Thanks again for the replies. I have 225Ahr (Trojans) and so the above suggests that something like a CTEK M300 might actually be sufficient?

 

[Mistroma]

Most battery manufacturers recommend a charging current of 20% of battery capacity (C) - that's C/5. Trojan recommend C/10 or 10%. Allowing for inefficiencies and the load taken by the boat a charger of C/4 or 25% of C would be best for most batteries. For your 450 Ah Trojans that should be about 13% or C/8 = a 60 amp charger. So you need one 50% bigger!


Most unlikely. You fudge factor is much too low...

Apologies for the thread drift. Might be of interest to OP as he has 225Ah Trojan's and is looking at 25A charger (Trojan suggest 30A and sailinglegend said 225/4 = 56A as a rough rule of thumb).

Thanks very much for the explanation. Charging & batteries state are always difficult to work out from theory as almost everything ends up being estimated. Useful to get another perspective. I've been steadily upgrading charging, batteries & DC powered items and a new charger is on my list. However, that was mainly to reduce time on generator if I've been at anchor for 2-3 days rather than for time on shorepower. I'd already worked out that Trojan suggested 60A (based on 13% of capacity as you said).

I measured charger output on several occasions from 50% - 60% starting points. Charger output held around 38A for 4 hours as you mention and then dropped. The results indicated that 100% was reached after 16 hours (or 12 hours starting from 100%). Smartguage % seemed to match the calculated level quite closely. I think largest difference was about 5% around 80-85% mark.

The data I had indicated that I was just at 100% after 16 hour charging from 50% but fine if starting from 60% (so fudge factor seemed reasonable initially).

If you expect the charger output to drop from 35A after 4 hours (my data agreed reasonably with this), then a larger charger would only help for a few hours. Does that sound logical? The batteries will accept a lot more than 40A initially so I assume that you are saying a 100A charger would probably push in 100A for an hour and then drop fairly quickly to same levels I'm getting from my 40A charger. I guess that this would mean I'd manage 100% charge after 10-12 hours with a 100A charger.

It seems as if I only need a larger charger for first few hours even on shorepower. However, it would be really useful to reduce generator running time at anchor (hate running the Honda for hours on end).

Does it sound sensible to buy a second single output 20-40A charger instead of replacing my existing charger? I'd get a backup charger and reduce charging times.

PS I actually changed my marina procedure once I arrived in the Rias. I can anchor nearby and go in around 10 in morning and leave about 15:00 next day with full tanks and decently charged batteries. So quick charging at anchor is now more important than quick charging on shorepower.

 

[sailinglegend420]

....then a larger charger would only help for a few hours.......... so I assume that you are saying a 100A charger would probably push in 100A for an hour and then drop fairly quickly to same levels I'm getting from my 40A charger............Does it sound sensible to buy a second single output 20-40A charger instead of replacing my existing charger?......

A larger charger will help in the "Boost" Stage, and a small part of the absorption - that will help when running on engine or generator as you will never leave them running for 12 hours during absorption.

Batteries will limit their charge to about C/4 when they are at about 60%, but if they are heavily discharged they could take a large inrush current and be damaged.

Yes buy a second (EDIT) SHOREPOWER CHARGER - same make and model as you have with the same charging voltages. During absorption mode as the current declines if one switches off then the other will deliver all the batteries needs. Same with alternator or solar regulators.

 

[Mistroma]

I have a spare alternator on board already but haven't installed it yet. I was actually asking about twinning different 240V chargers. If haven't seen much on this but suspected it might be OK in initial phase but need a rectifier to stop possible feedback when battery won't accept full output from both. i.e. They might hunt as one cuts back & other increases charge & vice versa.

Just wondered if you had any experience with that. I know that I could buy 2 identical chargers designed specifically for pairing but then I'd be better buying one large charger.

 

[multihullsailor6]

surprising, all ports in the SOF we have been, (except one, port Napoleon) is leccy included in the mooring price, also for long term.
which area / ports have you been ?

BartW,
In the Med I have been to Marina Bay in Gibraltar, Yacht Port Cartagena in Spain, Porto Rosa in northern Sicily, a marina on Lipari Island and now for winter I am in Marina di Ragusa in southen Sicily, all of which charge separatly for electricity and water. Coming to think about it, Columbus Yachting marina in Trapani, NW Sicily did have electricity and water included in the berthing fees.

 

[charles_reed]

I've been cruising now for 2 1/2 years, 1 1/2 years of which I have spent in the Med and must say that I have not come across many marinas in the Med which offer free electricity to long term berth holders - Cartagena in Spain until recently had a "all in" policy for monohulls but have changed that now as there was major abuse.

In my view shore power is vital in winter to keep the batteries topped up and to keep warm in the Med!

Probably the majority do, both in the Med and the Atlantic coasts - however if you picked your marinas by the ones who charged the least for multihulls I can well imagine you getting the impression it was always chargeable.
In France I found one of the ways of keeping people's usage down was to only supply 5 amp sockets - it was amazing how infrequently the power was tripped by those who cooked with electricity.

 

[OldBawley]

Looking at your intentions, the time passed in marina´s will be much less then you think. In lots of Med marinas, at 9 m you will have to pay the minimum charge witch is the same as for a 13 m yacht. Even if not mentioned in the price list, harbour masters will force that price on your small yacht. Wont take long before you anchor just next to the marina entrance.
The price for water and electricity is in a lot of marinas and town quays the same for you as for the 35 meter super yacht. So you will in fact pay for the big one. If you earned your money the hard way,then seeing others waste energy you have to pay for is no fun.
100 % load of battery’s is a long procedure, almost impossible if not constantly hanging on shore power. So why not bite the bullet and buy every three years new battery’s, it will be a lot cheaper than lying in marinas trying to charge up to 100 %.
We sail a small yacht as well, the boat has a shore connection and charger, we have not used it the last 10 years. I lived in a marina for ten years, now I prefer to anchor on a nice spot. Solar and wind power, good for 99,5% of the year, On those few inevitable dark and windless days I just start the diesel for an hour. ( No 100 % load )
As to the illegality to install stuff on your boat, don’t forget that once out of the North, you are in cowboy land. Nobody will tell you what to do or not to do.

 

[Caladh]

Hi. We're going to be moving aboard permanently this summer (yippeee!!) and then, hopefully, going through the canals to the Med not long after. We don't currently have shore power fitted, as we don't have any real need for it and we're keeping everything on board as simple as possible. We'll only have 12v electronics on board, we're electrically frugal (very, even on land!) and will have solar for battery charging plus motoring now and then, and we will have a charcoal Pansy for heating (maybe a little under powered in some places for a 30 footer, but we'll have blankets and hot water bottles too!). Our budget is going to be tight, but for us this lifestyle is about travelling and so we will want to visit larger towns and cities around the Med, and there's obviously over-wintering, and so some marina use is going to be unavoidable. Therefore, my question is, how often is electricity included for 'free' as part of marina berthing costs, as opposed to being metered? Is it more common in some countries than others?

Assuming that this is realistically likely to be somewhere where our budget is currently going to effectively be wasted, what is the easiest, KISS, and most cost effective option for installing a method of (worldwide) battery charging from a mains supply? Battery charging would seem to me to be the best method of utilising this 'free' resource, or are we overlooking/missing something else in our setup?

TIA!

Per other replies, you should fit a connection for 220/240volts AND a smart battery charger AND a high power alternator AND as many solar panels as you can afford/accomodate to your V30. Fit a 12v cigarette lighter socket for charging phones and mobile devices, rechargeable batteries etc Always charge something where your on the move under engine !

You haven't indicated whether you have a fridge but if you have you will need all of the above. We have come the long way round to Greece and used a variety of marina's, moorings and anchorages. The longest we have been at anchor/mooring is about 3 weeks before coming in somewhere for water/food/electricity/respite (!) etc If you are intent on visiting the sites in the Med, hire a car etc you are likely to want to leave your lovely bateau somewhere safe.....check you insurance requirements about leaving the boat as well. PM for more Vic.info. We also have another Vic30 in Messololonghi from your neck of the woods who could provided valuable info for you perhaps.

 

[syvictoria]

Thanks again for all the replies, particularly the ones from other KISS supporters, and fellow Vic owners!

This seems to fit the KISS principle perfectly, but is it suitable?

http://www.screwfix.com/p/nexus-13a-2g-rcd-switched-socket/91095#

Our current camping style RCD/single socket is faulty, and this would seem to be an ideal, and more permanent, replacement.

We don't have a fridge, only a Waeco coolbox (low power one), plus the standard insulated cool box. Whilst much of the gear mentioned above does sound very appealling, it's occurred to me that it could actually possibly be as cost effective to have a beer ashore every day, as to install and maintain the infrastructure required to have a cold beer aboard - not to mention that it would be more fun too!

We're putting in a new Beta 25 with a 70amp alternator, and we will have 90W of solar. With regards to consumption, we will have LED lighting, the normal boaty stuff (including Navtex and CP300, which will be the biggest boaty consumers), plus an iPod dock (12v), a low power Meos TV/DVD (12v) and 12v phone chargers... that's about it. Everything else will be manual - even our FM radio is wind-up!

Oh, and BTW, I'm a she!!!!

P.S.: Thanks very much for your pm Mistroma. We may well take up your offer of info once our plans are firmer!

 

[tri39]

https://www.roadpro.co.uk/retail/12...-triple-surface-mounted-power-socket-1030.htm

Save money at Roadpro. For example this triple socket I've found very useful to charge things while motoring!

As others have pointed out, the most powerful and expensive chargers are only used to full capacity for a very short time.
I've survived with very modest ones. KISS means anchoring most of the summer. When wintering in a marina, there's no rush to charge!
We are grateful for our fridge in the Med, esp for lunchtime beers. But warm red wine in the evening with warm mineral water is great too.
Tinned food provides most of our evening meals on board. Fresh food from restaurants! An iPad uses a fraction of the current of a laptop.
A windlass (well worth having) and HF transmission are usually only operated when the engine is already on.

 

[syvictoria]

This seems to fit the KISS principle perfectly, but is it suitable?

http://www.screwfix.com/p/nexus-13a-2g-rcd-switched-socket/91095#

Just to respond to my own questions... this has an RCD only and no MCB.

 

[RAI]

... but a vacuum cleaner on a 30' yacht - that possibly seems a little extravagant...!!!

Not after you have used a wet and dry one to vacuum out corners of bilges, catch shavings from holes drilled and get rid of a lot of sahara dust.

 

[tri39]

http://www.tooled-up.com/product/bl...oductlisting&gclid=CMGx5pCykrUCFQ7LtAodm0wAFg

I carry one of these to my own surprise! It can be useful especially after working/sanding/grinding inside and doesn't need shorepower.
Not very powerful, frequent emptying is required.