How big is your solar array

[FadeToScarlet]

2 x 100w flat stick on panels, running through an MPPT controller. Sufficient to run 12v fridge from early May to September ish with no Genny running at all. Keeps up with lights (Led) and phone charging over the winter, fridge off and food stored in a "bottomless cupboard" on the baseplate.

[Lmcgrath87]

If we are plugged into shore power most of the time is there much need for us to get solar?

 

It's on my want list, but I don't know if it's worth it currently.

[Staarek]

I've got 6 x 235w panels and I'm adding extra 2 for the winter... No genny/engine charging from mid feb till end of oct.

[KJT]

If we are plugged into shore power most of the time is there much need for us to get solar?

 

It's on my want list, but I don't know if it's worth it currently.

 

It's worth it certainly when you are out on the cut, especially if you spend any time in one location. If you cruise a few hours per day, then probably not. I have found when connected to shore power the solar charge drops significantly, I guess due to the charger giving a greater voltage than the solar controller and it shuts down the solar. However, I get around that by switching off the shore power charger during the day, especially if it's sunny, when we are on board, and then the solar panels take over the charge. So it is worth it. My prepaid electric meter credit lasts significantly longer if I can remember to switch it on/off as required.

 

Ken

[Lmcgrath87]

It's worth it certainly when you are out on the cut, especially if you spend any time in one location. If you cruise a few hours per day, then probably not. I have found when connected to shore power the solar charge drops significantly, I guess due to the charger giving a greater voltage than the solar controller and it shuts down the solar. However, I get around that by switching off the shore power charger during the day, especially if it's sunny, when we are on board, and then the solar panels take over the charge. So it is worth it. My prepaid electric meter credit lasts significantly longer if I can remember to switch it on/off as required.

 

Ken

 

Hurm, maybe still worth looking into then. I'm really surprised with how much electricity we get with our prepaid - £10 lasted us 10 weeks!

[Southern Star]

If we are plugged into shore power most of the time is there much need for us to get solar?

 

It's on my want list, but I don't know if it's worth it currently.

Certainly I think it's fair to say that the savings involved would be far less than the savings involved if the only other option for generating electricity was running the engine. However, it's really something for you to do the maths on, depending on your projected use of electricity.

[Drayke]

It's worth it certainly when you are out on the cut, especially if you spend any time in one location. If you cruise a few hours per day, then probably not. I have found when connected to shore power the solar charge drops significantly, I guess due to the charger giving a greater voltage than the solar controller and it shuts down the solar. However, I get around that by switching off the shore power charger during the day, especially if it's sunny, when we are on board, and then the solar panels take over the charge. So it is worth it. My prepaid electric meter credit lasts significantly longer if I can remember to switch it on/off as required.

 

Ken

Have you thought about putting your charger on a time switch.

 

Fred

[KJT]

Have you thought about putting your charger on a time switch.

 

Fred

Actually I did Fred. The problem is how would it know when it is sunny? Or when it's raining?

 

Ken

[Jim Batty]

2 x 100w panels on MPPT controller mean we don't have to run engine to re-charge battery bank between March and November. We CC slowly spending one week here, two weeks there. The two panels easily supply power to run 12v fridge, about 30 LED lights (not at the same time!), pumps and recharge the laptops and radio via inverter. We don't have a TV, but might watch iPlayer now and again.

 

I don't miss running the engine for a couple of hours on a nice sunny day.

Edited July 30, 2015 by Jim Batty

[rusty69]

2 x 250W flat on the roof connected in series through 60A MPPT controler charging 2 x 110 AH batteries.

[craftycarper]

If we are plugged into shore power most of the time is there much need for us to get solar?

 

It's on my want list, but I don't know if it's worth it currently.

 

. I am on 240 hook up as well, but the solar panel has saved loads, both in electric used by a battery charger and fuel used running the engine, also the battery's are fully charged when someone goes to the boat and you don't have to switch the charger on or run the engine for an hour when you get there, so I would say definitely worth getting, lastly I would imaging the battery,s will have a longer life because they don't get run so low and are being topped up all the time as well

[Terryb]

This has been very interesting to read guys, but I dont see anyone make mention of thier battery bank. (FYI I have 3 new 110ah) I am also very very jealous of everyone of you. Recently I had a 400wt system with MPPT controller fitted and yes it has done a good job. However, I only run a laptop my water pump and 5 LEDs when I need light mostly its just one. My problem is that while I am still not needing to run my engine for my imediate needs, I want to buy a TV to run through my inverter,and a 12v fridge but am not seeing or feeling that it will be enough. So far I have tried two very small fridges in the best of weather and they ran flat over night..

So along with all the information here, can you come back with acceptable battery bank size, volts max and min, I should be seeing. Also amps recieved and delivered I should expect. On a good day my volts at the panels rarely exceed 30 something, I have seen nearly 48 but very rarely. My imput hardly ever gets to more than 2-4 amps and my batteries average around the high 12v. Hope thats not too much to get your teeth into but I find it impossible to get an electrician down this way. Alan or Matty please visit.

Edited August 17, 2015 by Terryb

[matty40s]

Doesn't sound as though it's working as well as it should Terry. You should be able to run a fridge at this time of year no problem with that nuch solar and 3 new batteries.

What was your replacement inverter??

I would go for a 240v led smart TV which is a*** rated if I were you.

Again,,if your inverter is up to it, get a top rated 240v fridge, they are so efficient now, it should counteract any inverter power use.

What voltage are the panels - do you have 4 x 100w(12v) or 2 x 200w(24v).??are they wired in series or parralel, or both?

With a decent mppt and flat batteries you should easily be seeing 18-19A at first. You should also be seeing 80 plus V if wired in series ( best use if mppt ).

Your battery bank should be hitting 14 plus volts when sunny and charged for several hours, what voltage do you get when your engine us running??

 

Last and definitely not least, is anything casting even a small shadow on your panels, chimney, bike, rope, etc. Even one shaded cell can affect the whole array output.

Edited August 17, 2015 by matty40s

[jenevers]

Last and definitely not least, is anything casting even a small shadow on your panels, chimney, bike, rope, etc. Even one shaded cell can affect the whole array output.

My 800w is in a temporary setup at the mo and some of the cables are lying on top of the panels so I wonder just how much that is affecting the performance and what's the scientific explanation for a shadow on one cell affecting the whole setup?

[chubby]

Terry

 

Do u have a smartgauge ? theyre about £160 or so & look like an invention of the 1970 s but i absolutely would not be without mine , primarily because im not overly technical minded & im busy all the time .

I get back to my boat , check the gauge and its usually at 100 SOC ( state of charge ) all summer . Fridge (12v ) on all the time in summer , washing machine on , hoover on , eberspacher on most days ( in summer ) If i didn t have the smartgauge id often be thinking " how are my batts ? " . With the smartgauge i dont have to think about it at all . I press one button and the health of my batteries is known . Then i start turning things on . It also shows the voltage of the batts as the solar charges . I regularly see 13.5 - 14 + V in the daytime .

I cant really help with what might be wrong but as Matty says theres gotta be something somewhere thats not right as 400w ought to be enough for what youve described .

Aswell as checking your panels aren t shaded another thing perhaps to consider is how clean they are . I clean mine at least once a week to keep them at thier best . Are the panels all at the same angle ? This can affect the controller .

Anyway , just thoughts ... check out the smartgauge as it takes the guesswork away & u can see instantly whether your set up is performing as it should

Edited August 17, 2015 by chubby

[Terryb]

Thanks Mat, I knew you wouldn't let me down. I have a 1000 (peak 2000w) pure inverter and am so pleased that you mentioned the TV as I was/have been looking at just one such thing. Not wishing to be tied down to a 22 inch thing I was looking at a 32+ smart sub 50wt believing that my solar would be ok. My system is 12v in series I believe, (sorry not sure) but have never seen anything above 48v. As for shadows and stuff, I dont have a permanent mooring, so sometimes, where I am is hit or miss, but I do try to stay in the open.

Edited August 17, 2015 by Terryb

[matty40s]

your system should be giving you about 80v on a sunny day if wired in series and everything has been connected properly - ask the installer to confirm how it has been wired.

[Peter-Bullfinch]

We have a 2x100w Bimble set up. Cost just over £300 inc mppt controller. We are all 12v plus 12v TV and fridge and led lights. We charge 4x110 batteries. We are out from April to October but rarely stop for more than a week. We have virtually never had to run the engine to top up the batteries.

There are only two of us and read lots and listen to the radio a fair amount. Tv is a Cello and says it uses 16w.

[Top cat]

Ours is a 130w mono crystalline panel with an MPPT controller, we have stayed 3 days without running the engine during a fine sunny September weekend. Batteries were fine, butvas we were off the boat most of the time it was mainly running the 12V modern fridge freezer.

 

Top Cat

[Guest]

40 watts

[jenevers]

Aswell as checking your panels aren t shaded another thing perhaps to consider is how clean they are . I clean mine at least once a week to keep them at thier best .

My panels are semi flexible so they can't be cleaned as easily as glass as the surface would get scratched by the grit in the dust. After it has rained, then with some soapy water to soften the dust and with a micro duster I suppose would be the best approach.

[Ronniesonic]

300w on tilting brackets with MPPT controller on Acorn. Only ran Engine twice since April. Just to see if it still worked LOL. (except for a couple of trips out)

 

12v Fridge, stereo, gogglebox & LED lights.

 

Very impressed.

[Terryb]

Once again guys, I am impressed and still jealous. It would appear that my 400wt system has accumalated just 396ah in 3 weeks. Surely this can not be right. Or am I getting something wrong here.

[Scooby]

I have a 500 watt system. 3 x 165 actually. Wired in series I get over 100v everyday. Usually 60-130 amps per day during summer days. I think you need to check it's wired correctly and make sure the wire is thick enough. Minimum 6m2 upto the controller from the panels and 16m2 or thicker from controller to batteries. I got 38 amps yesterday and it rained all day.

[Scooby]

I also have a 32 inch smart 3dtv. It uses approx 50 watts. I use a small 600 watt inverter from maplin about £60 the inverter uses about 0.5 amps and the telly about 3. But I have wired in extension cables and also use my gaming laptop with separate monitor screen most nights. 12volt fridge uses approx 1.2 amps per hour and we have 4 x 110 amp batteries (cheap ones). We don't use the engine much in the summer apart from hairdryer and microwave use. We go out at the weekend most weeks.