Solar panels

[jaime66]

So we can have semi flexible panels and solid panels pro and cons for both ....but has any one fitted both at once on a boat .?...best of both worlds ...

[Jen-in-Wellies]

Not really, when there aren't any pros to flexis other than you can walk on them. Are you planning to do this, or is it just idle speculation?

Jen

[TheBiscuits]

9 minutes ago, Jen-in-Wellies said:

Not really, when there aren't any pros to flexis other than you can walk on them.

That's not quite true Jen.

 

They are better on caravans or motorhomes that travel at high speeds as they don't stick up very far.   

 

Some people prefer them on boats because they don't alter the appearance of the boat as much - with shapely lines this matters more than on square sided skips.

 

Other than that they cost more, wreck paintwork, overheat in summer so provide less power and don't last as long as rigid panels.

 

If @jaime66 still wants some, there are a pair of unisolars for sale on here at almost half price, and they are widely regarded as being the best of the stick down panels.

[robtheplod]

3 minutes ago, TheBiscuits said:

Other than that they cost more, wreck paintwork, overheat in summer so provide less power and don't last as long as rigid panels.

 

In my research this was the conclusion I came to also. Wouldn't it be great if you could get a slightly curved 'standard' panel that fitted the boat roof like a glove, that would be popular, especially if it had low profile magnetic fittings.

Edited July 21, 2020 by robtheplod

[TheBiscuits]

3 minutes ago, robtheplod said:

In my research this was the conclusion I came to also. Wouldn't it be great if you could get a slightly curved 'standard' panel that fitted the boat roof like a glove, that would be popular, especially if it had low profile magnetic fittings.

 

I know what you mean, but a convex curve would be the worst possible shape for a solar panel.  The sunlight could never be at optimum angle for power generation, so it would be rated at maybe two thirds of the power of an equivalent flat panel and cost about three times more!

[frangar]

24 minutes ago, TheBiscuits said:

That's not quite true Jen.

 

They are better on caravans or motorhomes that travel at high speeds as they don't stick up very far.   

 

Some people prefer them on boats because they don't alter the appearance of the boat as much - with shapely lines this matters more than on square sided skips.

 

Other than that they cost more, wreck paintwork, overheat in summer so provide less power and don't last as long as rigid panels.

 

If @jaime66 still wants some, there are a pair of unisolars for sale on here at almost half price, and they are widely regarded as being the best of the stick down panels.

I’ve got a pair of 120w 3rd gen CIGS panels supplied by midsummer. They are half the length of the unisolars for 20w less output...having said that those for sale on here are a good price!...time will tell how long they last but the adhesive on the back seems very good...like a layer of sticky bitumen...they are designed for metal building roofs so cope well with heat...I’m also getting 5 amps @ 12v when  it’s been raining and grey...in sun I easily get 12-14 amps. 
 

So far I’m a very happy bunny...and I haven’t changed the profile of the boat do ropes don’t get caught etc. 

[Jen-in-Wellies]

34 minutes ago, robtheplod said:

Wouldn't it be great if you could get a slightly curved 'standard' panel that fitted the boat roof like a glove, that would be popular, especially if it had low profile magnetic fittings.

And an extra curved version for Liverpool/Collingwood boats!

[blackrose]

1 hour ago, jaime66 said:

So we can have semi flexible panels and solid panels pro and cons for both ....but has any one fitted both at once on a boat .?...best of both worlds ...

What would be the point of that? The whole rationale for sticking flexible panels to a boat roof is that they can be walked on and don't change the roof profile. If you then install solid panels in addition then you defeat the purpose of the flexibles and probably end up with the worst of both worlds!  

[blackrose]

38 minutes ago, TheBiscuits said:

 

I know what you mean, but a convex curve would be the worst possible shape for a solar panel.  The sunlight could never be at optimum angle for power generation, so it would be rated at maybe two thirds of the power of an equivalent flat panel and cost about three times more!

 

Don't some of the newer panel technologies mean that angling the panel towards the sun is less important? I guess it's still better if you can though

[doratheexplorer]

57 minutes ago, TheBiscuits said:

 

I know what you mean, but a convex curve would be the worst possible shape for a solar panel.  The sunlight could never be at optimum angle for power generation, so it would be rated at maybe two thirds of the power of an equivalent flat panel and cost about three times more!

How about a curved panel with individually tilting solar cells?  So the overall structure would fit snugly but the active bits would still be looking at the sun?

[Alan de Enfield]

19 minutes ago, blackrose said:

What would be the point of that? The whole rationale for sticking flexible panels to a boat roof is that they can be walked on and don't change the roof profile. If you then install solid panels in addition then you defeat the purpose of the flexibles and probably end up with the worst of both worlds!  

I wonder if he meant mount the 'solid panels' above the stick-on ones (like a bunk-bed) so getting double the output for the same size space,

[PeterF]

8 minutes ago, doratheexplorer said:

How about a curved panel with individually tilting solar cells?  So the overall structure would fit snugly but the active bits would still be looking at the sun?

The tilted cells would shade each other.

[doratheexplorer]

2 minutes ago, PeterF said:

The tilted cells would shade each other.

No they wouldn't

[PeterF]

1 hour ago, Jen-in-Wellies said:

Not really, when there aren't any pros to flexis other than you can walk on them. Are you planning to do this, or is it just idle speculation?

Jen

I thought that walking on them was limited to soft soled shoes, most of use use more robust footwear when boating and if you had grit on your shoes or a stone trapped in the tread then walking on them would not be good. My boat came with them and I do not walk on them, luckily they are on the centre line with a gap to the handrails.

[matty40s]

29 minutes ago, Alan de Enfield said:

I wonder if he meant mount the 'solid panels' above the stick-on ones (like a bunk-bed) so getting double the output for the same size space,

Actually not such a mad idea, the latest technology has panels able to charge from both sides, reflected solar energy being used for the first time.

[cuthound]

9 hours ago, matty40s said:

Actually not such a mad idea, the latest technology has panels able to charge from both sides, reflected solar energy being used for the first time.

 

But wouldn't you need a mirror finish on the roof for best results? ?

[matty40s]

12 minutes ago, cuthound said:

 

But wouldn't you need a mirror finish on the roof for best results? ?

White or cream would suffice.

[frangar]

17 minutes ago, cuthound said:

 

But wouldn't you need a mirror finish on the roof for best results? ?

Stainless steel shell obviously 

[mark99]

The 200w flexi ones I fitted throw out over 200w in summer.  219 W.  So not sure where this inefficiency at hot times comes from.

 

Not everyone wants a roof covered in carbunckle formats.

Edited July 21, 2020 by mark99

[Cheshire cat]

Where did you get yours from Mark?

[frangar]

12 minutes ago, mark99 said:

The 200w flexi ones I fitted throw out over 200w in summer.  219 W.  So not sure where this inefficiency at hot times comes from.

 

Not everyone wants a roof covered in carbunckle formats.

I think you’ve got the same as me...and from 2 120w panels today I got 277w....even on the 25c days I’ve been getting over 200w too. 

[matty40s]

There is a difference, the flexible ones are good, I will use them. The semi flexible ones are good for a year or two on boats and then die.

[jaime66]

OK so best to go with solid panels .... Thanks for all the input !

[Paul Gwilliams]

You could always use brackets for solid panels that allow you to adjust the height.

 

You will still have the brackets visible but they cause less of a rope snagging hazard or it may just be me being cack handed when it comes to ropes