The Big Solar Install

[blackrose]

So what about Loddon's point about using higher voltage panels? Why does anyone use 12v panels and why do outlets like Bimble base the majority of their sales for mobile users on 12v panels if they don't produce the best results? I'm struggling to get my head around it. 

[Alan de Enfield]

1 hour ago, blackrose said:

So what about Loddon's point about using higher voltage panels? Why does anyone use 12v panels and why do outlets like Bimble base the majority of their sales for mobile users on 12v panels if they don't produce the best results? I'm struggling to get my head around it. 

 

My 120v panels were from Bimble.

 

Bimble seem to sell whatever panels they can buy - particularly 'part-used' ones.

The 120v ones I had were allegedly 'low light panels** from a Scandinavian solar farm'.

 

**Apparently low light as in designed for use in higher latitudes where the angle of the Sun is lower in the sky - NOT - 'low light' as in 'dawn or dusk'

[LadyG]

On 16/06/2022 at 09:21, ASupertramp said:

 

Still deciding. It will definitely be something that I can angle but want to try and stay away from the triangle ones. 

 

 

I was basing this on the Nominal PV power on the data sheet - the 100/50 goes up to 700w and I have 1200w?

I think the bracket angling business was developed when panels were really expensive, personally I'd just keep it simple. minimal drilling,

People have engineered fancy designs, but in the end, it makes little difference unless you can angle your panels to the sun, turning continuously., And of course they would take off in stormy weather if they were perfect in that regard.

Edited June 18, 2022 by LadyG

[bizzard]

48 minutes ago, LadyG said:

I think the bracket angling business was developed when panels were really expensive, personally I'd just keep it simple. minimal drilling,

People have engineered fancy designs, but in the end, it makes little difference unless you can angle your panels to the sun, turning continuously., And of course they would take off in stormy weather if they were perfect in that regard.

You need to plant Sunflowers and fix lots of little panels on em, then they'll always automaticaly face the sun.

[LadyG]

3 hours ago, bizzard said:

You need to plant Sunflowers and fix lots of little panels on em, then they'll always automaticaly face the sun.

Don't be silly, that would only work from March to October!

[blackrose]

11 hours ago, Alan de Enfield said:

 

My 120v panels were from Bimble.

 

Bimble seem to sell whatever panels they can buy - particularly 'part-used' ones.

The 120v ones I had were allegedly 'low light panels** from a Scandinavian solar farm'.

 

**Apparently low light as in designed for use in higher latitudes where the angle of the Sun is lower in the sky - NOT - 'low light' as in 'dawn or dusk'

 

Yes I know Bimble sell higher voltage panels, but as I said, the majority of their panels (and I suspect the majority of its business) for boats, vans etc is 12v.

 

We talk endlessly on this forum about rigid or flexible panels, angled or not, the best type of controllers, isolators, etc, etc, but not so much about panel voltage. Most people like myself who don't know a lot about the subject, assume that 12v panels should be used on 12v systems. I don't really understand why Victron and other manufacturers produce 12v panels for boats or why most people on this forum are fitting 12v panels if higher voltage panels would produce better results? Just seems like a fundamental aspect isn't being fully explored in many of these discussions. 

[LadyG]

Try Will Prowse on YouTube, he explores all aspects of off grid solar.

Of course he lives in Nevada, but that should not affect the basics.

Or ask Bimble, don't forget they sell kits which are discounted. I expect other suppliers do the same.

Edited June 19, 2022 by LadyG

[Alan de Enfield]

7 hours ago, LadyG said:

Don't be silly, that would only work from March to October!

 

Just the same as 'normal' solar panels then !

[Alan de Enfield]

1 hour ago, blackrose said:

I don't really understand why Victron and other manufacturers produce 12v panels for boats or why most people on this forum are fitting 12v panels if higher voltage panels would produce better results?

 

 

I don't think you actually mean 12v panels, as you could not charge a 12v battery with a 12v solar panel - the panel must be capable of outputting at least 15 volts as an absolute minimum so the battery can get its charge at 14.2 - 14.6 volts.

 

I agree many panels used on boats are in the 19v to 30v range (for some reason I do not understand)

 

When I explained to Bimble what my set-up was (boat) it was them that suggested the 120v panel with an MPPT as being the most efficient option.

 

I wonder if people actually "talk" (verbally) with the likes of Bimble and use their expertise ?

 

Both of my Sons seem loathe to actually talk to anyone - they just send simple texts which I find is not conducive to good information gathering.

 

As Busby used to say .............. "It's good to talk"

 

 

 

 

[ditchcrawler]

4 hours ago, blackrose said:

 

Yes I know Bimble sell higher voltage panels, but as I said, the majority of their panels (and I suspect the majority of its business) for boats, vans etc is 12v.

 

We talk endlessly on this forum about rigid or flexible panels, angled or not, the best type of controllers, isolators, etc, etc, but not so much about panel voltage. Most people like myself who don't know a lot about the subject, assume that 12v panels should be used on 12v systems. I don't really understand why Victron and other manufacturers produce 12v panels for boats or why most people on this forum are fitting 12v panels if higher voltage panels would produce better results? Just seems like a fundamental aspect isn't being fully explored in many of these discussions. 

But 12 volt panels are not 12 volt they are probably about (because I haven't checked) 18 volts and with a cheap PWM controller or an expensive fake MPPT one are more efficient than higher voltage panels. 

 

[blackrose]

3 hours ago, Alan de Enfield said:

 

I don't think you actually mean 12v panels, as you could not charge a 12v battery with a 12v solar panel - the panel must be capable of outputting at least 15 volts as an absolute minimum so the battery can get its charge at 14.2 - 14.6 volts.

 

I'm just going by what they're called on the Bimble website. Perhaps Bimble don't actually mean 12v panels, but if the experts use that nomenclature then perhaps a solar novice such as myself can be forgiven for doing the same. 

 

11 minutes ago, ditchcrawler said:

But 12 volt panels are not 12 volt they are probably about (because I haven't checked) 18 volts and with a cheap PWM controller or an expensive fake MPPT one are more efficient than higher voltage panels. 

 

 

But they're called 12v panels and on my other solar thread both Loddon and Alan agreed that panels of 40v + are more suitable and efficient in low light situations. So my general point stands. Most people seem to be installing "12v panels" with insufficient voltage output and this issue isn't being fully discussed on the forum. 

Edited June 19, 2022 by blackrose

[Alan de Enfield]

9 minutes ago, blackrose said:

But they're called 12v panels and on my other solar thread both Loddon and Alan agreed that panels of 40v + are more suitable and efficient in low light situations. So my general point stands. Most people seem to be installing "12v panels" with insufficient voltage output and this issue isn't being fully discussed on the forum.

 

From my personal experiences I completely agree with you, BUT, I wonder if it is to do with the 'Low Voltage Directive' which covers DC above 75 volts and has some tight restrictions about who can install and what qualifications are needed.

 

our "12 volt" systems are classed as "Extra Low Voltage" and has much lower standards of regulation that 'Low Voltage'

 

Who enforces the Low Voltage Directive?

In the UK, the LVD is officially implemented by The Electrical Equipment (Safety) Regulations 1994. These regulations are enforced by the Health and Safety Executive (HSE) when LVD-relevant electrical equipment is used in the workplace or non-domestic premises. The Trading Standards Service enforces regulations when LVD-relevant electrical equipment is used at home.

What are the penalties for non compliance?

Businesses not complying with LVD requirements are committing an offence and risk a fine, imprisonment, or both. The HSE can ask for electrical equipment to be withdrawn from the market if it is not LVD-compliant. Notifications of these withdrawals are then made to the European Commission by the Department for Business, Innovation & Skills.

[ASupertramp]

20 hours ago, LadyG said:

I think the bracket angling business was developed when panels were really expensive, personally I'd just keep it simple. minimal drilling,

People have engineered fancy designs, but in the end, it makes little difference unless you can angle your panels to the sun, turning continuously., And of course they would take off in stormy weather if they were perfect in that regard.

There are some figures floating around showing the increase when tilting, particularly in winter but you’re correct in that it would then require tilting throughout the day, which may not be practical for me as I’ll be at work. 
 

Does this look like the best way to wire the 230v side? I wasn’t sure whether to put the RCD before or after the inverter but with wanting to isolate the immersion from the inverter side, this seems to make sense? Switch not required as the victron auto switches between shore power and inverter. 

Edited June 19, 2022 by ASupertramp

[blackrose]

On 19/06/2022 at 12:52, Alan de Enfield said:

 

From my personal experiences I completely agree with you, BUT, I wonder if it is to do with the 'Low Voltage Directive' which covers DC above 75 volts and has some tight restrictions about who can install and what qualifications are needed.

 

our "12 volt" systems are classed as "Extra Low Voltage" and has much lower standards of regulation that 'Low Voltage'

 

Who enforces the Low Voltage Directive?

In the UK, the LVD is officially implemented by The Electrical Equipment (Safety) Regulations 1994. These regulations are enforced by the Health and Safety Executive (HSE) when LVD-relevant electrical equipment is used in the workplace or non-domestic premises. The Trading Standards Service enforces regulations when LVD-relevant electrical equipment is used at home.

What are the penalties for non compliance?

Businesses not complying with LVD requirements are committing an offence and risk a fine, imprisonment, or both. The HSE can ask for electrical equipment to be withdrawn from the market if it is not LVD-compliant. Notifications of these withdrawals are then made to the European Commission by the Department for Business, Innovation & Skills.

 

Would these panels meet the 40 Voc + specification? I can see a couple of different voltage figures given in the product specs 

 

https://www.bimblesolar.com/375w-canadian-solar-panel

[Tony Brooks]

12 minutes ago, blackrose said:

 

Would these panels meet the 40 Voc + specification? I can see a couple of different voltage figures given in the product specs 

 

https://www.bimblesolar.com/375w-canadian-solar-panel

 

Yes, because the link gives 41V as the Voc value while for maximum power (which the MPPT controller should keep pretty close to) the value is 37V. I don't know, but suspect the lower figure has something to do with the internal resistance of the panel.

[Alan de Enfield]

10 minutes ago, blackrose said:

 

Would these panels meet the 40 Voc + specification? I can see a couple of different voltage figures given in the product specs 

 

https://www.bimblesolar.com/375w-canadian-solar-panel

 

With 41 VoC they would certainly fall below 75 volts so would fall into the ELV rating.

 

"26 % higher power than conventional modules"

 

Is an interesting statement I wonder if there are test result to show that ?

[blackrose]

7 minutes ago, Alan de Enfield said:

 

With 41 VoC they would certainly fall below 75 volts so would fall into the ELV rating.

 

 

Ok, I thought Julian (Loddon) said I should be looking for 40 Voc + so would these be ok? 

Edited June 21, 2022 by blackrose

[Alan de Enfield]

55 minutes ago, blackrose said:

 

Ok, I thought Julian (Loddon) said I should be looking for 40 Voc + so would these be ok? 

 

Yes.

"40V +" could be 50, or 60 or 74.9 volts, the higher the better.

 

As I mentioned I have 120v panel and for every amp that comes out of the panel I get 7 or 8 amps at (14.2-14.4 volts) from the MPPT being 'squirted' into the batteries.

[GUMPY]

My two banks of panels are chugging along at 195v but only (due to the time of day) producing 2.27kW, just over half capacity

 

That is six 365watt panels in each bank wired in series. 

 

 

ds_rec_twinpeak_4_series_en.pdf

Edited June 21, 2022 by Loddon

[blackrose]

Thanks. I've gone back to Bimble to ask if they can recommend any higher voltage panels. To be honest I'm not sure if they really know their stuff as they disregarded what you'd said about using higher voltage panels and said a lot of things said on forums wasn't relevant, without any explanation or justification. I'll probably go elsewhere and put my own kit together. 

Edited June 21, 2022 by blackrose

[ASupertramp]

Well the panels arrived today. Needless to say, measuring does not compare to an actual 3D object, these things are huge. 

[GUMPY]

5 minutes ago, blackrose said:

Thanks. I've gone back to Bimble to ask if they can recommend any higher voltage panels. To be honest I'm not sure if they really know their stuff as they disregarded what you'd said about using higher voltage panels and said a lot of things said on forums wasn't relevant, without any explanation or justification. I'll probably go elsewhere and put my own kit together. 

If you cant get panels that have a higher oc voltage to get the voltage up you could, as I said earlier, wire 4 panels in series/parallel

 

[Puffling]

54 minutes ago, ASupertramp said:

Well the panels arrived today. Needless to say, measuring does not compare to an actual 3D object, these things are huge. 

Looking very nice, though.

Just out of interest, did the courier turn up at the time they advised?

I'm also getting three panels from Bimble later this week ⚡

[ASupertramp]

11 minutes ago, Puffling said:

Looking very nice, though.

Just out of interest, did the courier turn up at the time they advised?

I'm also getting three panels from Bimble later this week ⚡

I received a phone call when I ordered asking if I could take delivery today, then an email last night with confirmation that they would be out for delivery today with a three hour time slot. This morning a text from the delivery man saying he would ring when within 20 mins and to text him if needed. They turned up bang on time and carried the panels to the boat for me. 
Can’t fault them. 
 

While I’m at it, Alpha Batteries have been excellent after I ordered the wrong MPPT, refunded, changed and new one sent out within a day. 

[Puffling]

1 minute ago, ASupertramp said:

I received a phone call when I ordered asking if I could take delivery today, then an email last night with confirmation that they would be out for delivery today with a three hour time slot. This morning a text from the delivery man saying he would ring when within 20 mins and to text him if needed. They turned up bang on time and carried the panels to the boat for me. 
Can’t fault them. 
 

While I’m at it, Alpha Batteries have been excellent after I ordered the wrong MPPT, refunded, changed and new one sent out within a day. 

Very reassuring, thanks for providing the details.

 

I'm having my panels delivered to a marina, but I'm not there now, so it's good to know I'll be able to advise them of the delivery on the day they are due.