Solar charger help plz

skipper681

skipper681

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I'll apologise in advance because I know it's been discussed here countless times but could someone please help, I'm still trying to get it through my thick skull :D

I've a small 19ft sailing boat, no electrics at the moment but I'll be running a garmin plotter, a VHF and a trilight at the mast. I have a brand new 60ah battery, is the battery enough and how do I solar charge it.

I've heard the term regulator, so it dosen't overcharge???

Confused

:confused:
 
buy a solar charger from Maplin or Halfords, connect it to the battery and place the panel in the window or on deck, this will keep your battery topped up. regulator is built in.

Or

Give Lloyd West a call at Marlec and he will give you all the advice and assistance you will need along with all the parts cables and connections.
 
not all of Maplins and Halford's panel have regulators built in.

I think you need to be a bit more techncial than just adding a panel. Start by calculating the max consumption in any 24 hours.

e.g. (and figures vary enormously depending on the make, usage pattern,etc)

VHF (fixed ?) 5Ah
Nav Light 10Ah
Plotter 15Ah

Total 30Ah !!!

Now that is pretty much worst-case stuff, and shows how much power will be taken out of your 60Ahr battery, i.e. nearly everything. Very roughly you will therefore need to replace double that bcause batteries do not charge very well on a 'straight' DC input so you need panel which can input 60Ah in any 24 hrs.

In the UK that is a really big panel; far too big for your 19ftr unless you want to use it as a sail as well.

Remedies.
Get some hard info on the power consumption of your proposed kit. For instance are you going to use the nav lights every night ? The plotter for 10 hours a day ?

Go for LEDs

Handheld VHF

Buy a larger battery, say 180Ahr, which will not be depleted quite so much by one full day's sailing, and which can build up a charge steadily when you are not using the boat.

At a very rough guess, a 40 watt panel plus separate regulator would be a starting point.
 
OK, we have to make a few assumptions here but being a small boat I suspect your night time sailing will be limited and unless you intend to talk to lots of people on the VHF it will be for important safety messages and the occasional call. In general then that will leave you with the power consumption of the plotter over the period you are sailing to worry about. I suspect you battery will be fine for a weekend. Now, what size solar panel do you intend to fit? This will determine if the battery will re-charge between sails. The bigger the panel the quicker it will recharge. I would advise fitting a controller of the type that has 3 connections, one for the solar panel, one to the battery and one for your electrical load. This will disconnect the load if your battery drops to the point where you are discharging it to the point of damaging it. It will also prevent over charging of your battery and in general they have an indicator to show battery state. There are all sorts out there and I have had 2 off e-bay with no issues. I also have one that splits load between 2 batteries which is good if you choose to add a second battery. They are certainly cheap enough and I would always advise fitting one.

Yoda
 
Solar charging

First you have the 60AH battery and I would expect that it will have enough capacity for your needs.
I assume like me you sail on weekends in summer. You have occasional need for lights for a few hours.
depending on the amount you use your lights LED will be far more efficient on battery power.
I think you will find that a 10 w panel will keep the battery charged as you need and recharge over a week or 2. You do not need a regulator with 60AH battery and 10w panel.
To give you an idea I use an old solar panel that generates about 3w into about 10AH demonstrated NiCad battery. This easily keeps up with my occasional (once per month night race of about 3hrs) I don't run a plotter just VHF and LED lights. The panel is attached with bungee over the boom sail cover and the boat is on a swing mooring.
So get a 10w panel easily mounted as mine is connect it up and give it a try. (make sure it has a built in diode (as most have) to stop discharge at night) If you find the battery is overcharging I can't imagine it will, then fit a regulator. If it is not keeping the battery up with your use then add another panel.
here is one from China that should suit. It may need a schotky diode less than a squid from RS or similar.
http://www.ebay.com.au/itm/mono-sol...v-panel-solar-module-/261001665612#vi-content
At about 20 squid you can't go wrong. There are many more good luck olewill
 
sarabande said:
not all of Maplins and Halford's panel have regulators built in.

I think you need to be a bit more techncial than just adding a panel. Start by calculating the max consumption in any 24 hours.

e.g. (and figures vary enormously depending on the make, usage pattern,etc)

VHF (fixed ?) 5Ah
Nav Light 10Ah
Plotter 15Ah

Total 30Ah !!!

Now that is pretty much worst-case stuff, and shows how much power will be taken out of your 60Ahr battery, i.e. nearly everything. Very roughly you will therefore need to replace double that bcause batteries do not charge very well on a 'straight' DC input so you need panel which can input 60Ah in any 24 hrs.

In the UK that is a really big panel; far too big for your 19ftr unless you want to use it as a sail as well.

Remedies.
Get some hard info on the power consumption of your proposed kit. For instance are you going to use the nav lights every night ? The plotter for 10 hours a day ?

Go for LEDs

Handheld VHF

Buy a larger battery, say 180Ahr, which will not be depleted quite so much by one full day's sailing, and which can build up a charge steadily when you are not using the boat.

At a very rough guess, a 40 watt panel plus separate regulator would be a starting point.
Click to expand...

An alternative approach is to fit the biggest panel that you can comfortably have on you boat, put a simple on-off regulator in the line and then work out how much you will possibly get out of it (I'd suggest about 50% of the stated output) and the live within those means.
Even a small 10W panel should re-charge your battery fully throughout the week between weekend use.

A 20W panel keeps my 140 AH replenished between light weekend use.
 
Wiiliam H has given you some sound advice.
Unless you are using your boat for regular and bigger trips than most people would do in a 19 footer then a 60ah battery and 10watt panel will be absolutely fine. The occasional big trip will drain the battery but the following few days will charge it up again.
More than likely you won't need to fit a regulator either.

In any event you would probably struggle to fit anything bigger than a 10 watt panel on your boat.
 
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I also have 19ft boat .

I have a full set of nav lights ( P, S, stern and masthead) and a tricolour which now has an LED bulb.

I have plenty of cabin lighting ( not yet converted to LEDs)

Echosounder

VHF ( Seldom transmit though)

Autohelm ..... (in near continuous use)

I also have a hand held spotlight with a deck socket to power it

This is all powered from a 60Ah battery

The anchor light is a battery powered LED lantern

The battery is charged by a fixed 5 watt Spectralite solar panel plus a very small contribution from the outboard engine.

If I'd had a suitable space i would have fitted a 10 watt solar panel but the 5 watt one has proved adequate for my needs
I'd probably supplement it with a larger temporary panel if I were to do more than weekend, plus the occasional week, sailing.

For pottering around the solent i dont need a plotter... i seldom even need to refer to a chart. If I were to venture further I would probably buy some new charts and a H/H gps

No regulator is needed for the 5watt panel in conjunction with a 60Ah battery . A 10 watt one , or larger, would need a regulator
 
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I used to have a 17 footer with interior light, tricolour, vhf and handheld gps. I fitted a 55 ah battery and 10w solar panel. This kept up the battery just fine. On a small boat space for both battery and panel are at a premium and govern the size of both. As previously stated you need to do an audit of power you use. The usage on a small boat will be different from a large cruiser. If I were to repeat my installation I'd include a simple regulator as they're only a tenner.
 
ghostlymoron said:
I used to have a 17 footer with interior light, tricolour, vhf and handheld gps. I fitted a 55 ah battery and 10w solar panel. This kept up the battery just fine. On a small boat space for both battery and panel are at a premium and govern the size of both. As previously stated you need to do an audit of power you use. The usage on a small boat will be different from a large cruiser. If I were to repeat my installation I'd include a simple regulator as they're only a tenner.
Click to expand...

With a 10watt panel and a 55Ah battery I would definitely fit a regulator. I'd add one to the existing circuit. Simple enough to do.

The rule of thumb is that up to 1 watt per 10Ah does not need a regulator but one should be fitted if the ratio is greater or if the panel exceeds 10Ah.
 
VicS said:
With a 10watt panel and a 55Ah battery I would definitely fit a regulator. I'd add one to the existing circuit. Simple enough to do.

The rule of thumb is that up to 1 watt per 10Ah does not need a regulator but one should be fitted if the ratio is greater or if the panel exceeds 10Ah.
Click to expand...
When I did the original installation I knew nothing about boats or solar so didn't fit a regulator. But the battery survived 4 years and afaik is still going strong. Maybe we're not getting enough sun - certainly feels like it! Knowing what I do now, and as regulators are now very cheap (simple ones anyway) I'd fit one.
 
Thanks for the replys. the VHF is http://www.force4.co.uk/468/Cobra-F55-Waterproof-DSC-VHF-Fixed-Radio.html and the plotter is https://buy.garmin.com/shop/shop.do?pID=28742&pvID=30111&ra=true I haven't got the tri light yet but when I do it will be an LED bulb.

I'm no good at the calculations :confused: but I'll be using the boat at weekends so it will have all week to charge up so if I get the 5w spectralite would that suffice?

Regulator? I know you say for a 5w I wouldn't need one but for the sake of a tenner is it better to be safe than sorry as I will probably be away from the boat 3 or 4 days at a time?

Thanks
 
I'd go for the 10w @ £95 rather than the 5w @ £70 you get a lot more bangs for your buck. But it depends on whether you've got room. I like the semi flex panels rather than the floppy ones that you deploy on a temporary basis.
 
skipper681 said:
Thanks for the replys. the VHF is http://www.force4.co.uk/468/Cobra-F55-Waterproof-DSC-VHF-Fixed-Radio.html and the plotter is https://buy.garmin.com/shop/shop.do?pID=28742&pvID=30111&ra=true I haven't got the tri light yet but when I do it will be an LED bulb.

I'm no good at the calculations :confused: but I'll be using the boat at weekends so it will have all week to charge up so if I get the 5w spectralite would that suffice?

Regulator? I know you say for a 5w I wouldn't need one but for the sake of a tenner is it better to be safe than sorry as I will probably be away from the boat 3 or 4 days at a time?

Thanks
Click to expand...

Entirely up to you whether or not you fit a regulator. I considered it when I had a smaller battery but I see no reason for it with the 60Ah battery.

You VHF RT will consumes 5 amps when transmitting at full power, only 1 amp at low power, 200mA (0.2amps) when receiving and 20mA (0.020amps) when just on standby.

Multiply the above amp figures by the number of hours the set will be in each mode during the course of a weekend and add the results together to arrive at how much it will consume, in Amphours, in the course of a weekend.

You plotter uses a max of 15 watts (at 13.8 volts) that's equal to approx 1.1 amps. Multiply the number of hours it will be in use by 1.1 to get a weekend consumption in amphours. ( There is no breakdown of the 15 watts. Obviously less if the sonar is not used and less when the back lighting is off or reduced)

Do the same for all your lights and other electrical equipment. ( amps x hours in use)

Add all the amphour figures together to get your total electrical consumption for a weekend.

Your battery capacity should be no less than double this total.

The data for your solar panel should include a typical daily output figure in amphours. Ensure that you choose a panel where 7 times this typical daily output comfortably exceeds your calculated total electrical consumption.

All being well you can then assume that your battery is large enough not to suffer from being too deeply discharged and that your solar panel will recharge your battery.

If you will be using the boat for longer periods you will need to recalculate on the basis of the number of days you will be using it per week.
 
ghostlymoron said:
I'd go for the 10w @ £95 rather than the 5w @ £70 you get a lot more bangs for your buck. But it depends on whether you've got room. I like the semi flex panels rather than the floppy ones that you deploy on a temporary basis.
Click to expand...

I think you can do a lot better for a lot less money. Have a look at Sunstore You could have 40w of panel and a controller to for about £70, but you will have to mount them properly where they won't get walked on. Even with 20w you'll need a controller, but you can afford it at their prices!

There's a rough & ready formula for how much you get from solar panels in the UK; the output in amp hours = rated output of panels/4, so I expect my 40w of panels to give me about 10ah per day.
 
I have been thinking about adding a solar panel to my boat which has 2 batteries, 80 AH each. There is room at the stern for two small ones that will stand being stood on, ie semi flexible.

I have some exp of solar panels from my previous smaller boat. My question is how do you charge both batteries from one panel. Are they connected to each other electrically?
 
Enya said:
I have been thinking about adding a solar panel to my boat which has 2 batteries, 80 AH each. There is room at the stern for two small ones that will stand being stood on, ie semi flexible.

I have some exp of solar panels from my previous smaller boat. My question is how do you charge both batteries from one panel. Are they connected to each other electrically?
Click to expand...
It depends on how your batteries are wired. The most usual way (arguably) is to have a dedicated engine battery and a 'house' battery. If that is the case, the engine battery will be re-charged within a short time of starting the engine (say 15min), the 'house' battery can be re-charged from solar (or engine if running for > 15min). If you have 2 solar panels, they should be connected in parallel to the 'house' battery through a regulator.
 
Enya said:
I have been thinking about adding a solar panel to my boat which has 2 batteries, 80 AH each. There is room at the stern for two small ones that will stand being stood on, ie semi flexible.

I have some exp of solar panels from my previous smaller boat. My question is how do you charge both batteries from one panel. Are they connected to each other electrically?
Click to expand...

If your batteries are connected together in parallel as a single 160 Ah bank then just charge them as one large battery.

If the batteries are not connected together, perhaps you use one or the other via a selector switch or perhaps one is the engine start battery and the other the domestic services battery then either charge then via a diode splitter or by using a regulator with two outputs.
Alternatively just charge the domestic battery and let the engine maintain the starter battery, or even fit two solar panels, one for each battery
 
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