Solar Panles, Aircon and Generators

[Billggski]

"Some converters to link it all up" may be the most important fittings you buy.

[TheEscapist]

Billggski - 2019-03-19 11:19 PM

 

"Some converters to link it all up" may be the most important fittings you buy.

 

I’m requesting a schematic.....

 

———-

 

In my opinion, given your apparent situation, whilst I’d not necessarily specify the make of solar panels to fit (most are manufactured in Asia these days) I would ask your installer to produce a schematic of their proposed solar installation for your approval.

 

In particular, I’d expect non flexible solar panels, ie ridged monocrystalline with aluminium frames and glass faced, a best of class motorhome specific solar regulator that charges both the habitation batteries and trickle charges the starter batter (a favourite amongst some of us is the Votronic MPPT duo -– there may be alternatives), I’d expect the regulator to be installed close to the habitation batteries and I’d expect the output of the regulator to be fed directly into the EBL rather than directly to the batteries – that way the EBL will correctly monitor habitation battery charge/usage.

 

———

[BruceM]

TheEscapist - 2019-03-19 10:32 PM

 

Billggski - 2019-03-19 11:19 PM

 

"Some converters to link it all up" may be the most important fittings you buy.

 

I’m requesting a schematic.....

 

———-

 

OK – PC Logic is a brand name of these guys https://www.solartechnology.co.uk/ and their PV Logic range is outlined here https://www.solartechnology.co.uk/solar-panels/pv-logic-panels .

 

I get the impression that they mostly supply solar panel kits which is probably why they’re popular with installers.

 

The solar regulator looks similar to the one I removed from my van. It appears to be this one (the link also provides a datasheet) https://uk.rs-online.com/web/p/solar-power-regulators/9054532/ . Not best in class imho.

 

I’ve assumed that your van’s EBL does not come with a built in solar regulator . There are other’s on the forum with greater expertise than I who might advise. It’s possible that modern EBL’s are all signing all dancing these days. If it does have a built in solar regulator then you might just need solar panels on the van roof and cabling to the EBL. A much more straightforward proposition.

[globebuster]

Don't overlook the physical installation on to the roof!

 

Ensure you have a decent brackets or a subframe of some sort, with the correct adhesive and a mechanical fixing if you're really concerned.

 

Most thru roof glands offered are frankly crap! I would 'Spec Up' with some decent marine grade ones.

[TheEscapist]

I have searched hi and low for PV Logic solar panel reviews and found none which in itself concerns me.

 

Does anyone have any experience of them. Has anyone used them?

 

I’m confident on the dealers fitting capability but I am concerned that maybe the solar panel brand is more convenient for them than best in class.

 

Can anyone recommend the best brands that come in multiple size options for my roof as I’m fitting around the other vents etc.

 

Thanks!

 

Paul

[globebuster]

Photonic Universe - well used in marine applications or - Solar Technology International.

[TheEscapist]

I need to tell the dealer today the brand of solar panels I want fitting.

 

Can I get a quick input from as many as many of you as possible on the best brand in terms of quality, multiple sizing solutions and associated converters/ monitors etc?

 

Photonic Universe?

Solar Technology Intl?

Any others?

 

Thanks

 

Paul

[BruceM]

TheEscapist - 2019-03-20 2:07 PM

 

I need to tell the dealer today the brand of solar panels I want fitting.

 

Can I get a quick input from as many as many of you as possible on the best brand in terms of quality, multiple sizing solutions and associated converters/ monitors etc?

 

Photonic Universe?

Solar Technology Intl?

Any others?

 

Thanks

 

Paul

 

The trouble is, most of us will have anecdotal recommendations probably borne out of a single purchase. It’s also probable that several brands are rebadged solar panels produced in the same Chinese factory.

 

So for instance I bought my panels from these guys https://uk.renogy.com/products/components/solar-panels/ via ebay (they no longer appear to sell via that channel). The data sheet for their panels ticked all my boxes and 2 x 100W was under £180 delivered. The panels appear to be doing what I expected of them. But then they’ve only been in use just over a year – we’ll see how they are in ten years time.

 

As far as solar regulators go, my vote would be the Votronic MPPT Duo of appropriate wattage for the panels you have.

 

As as far as monitors are concerned, if it’s wired via the EBL then why have a separate solar monitor? If the sun’s out there will be power available and the EBL should provide feedback on the habitation battery states. For instance, when I have the heating on during the day today, I can see from the EBL control panel that there’s no draw on the batteries, that’s because the solar panels are providing all my power requirements.

 

[globebuster]

 

 

My recommendations were borne out of use in leisure and commercial application.

 

I wish you well with the new van, but I fear you are getting into the 5 P's territory with the whole thing now.

 

 

[TheEscapist]

globebuster - 2019-03-20 6:44 PM

 

 

 

My recommendations were borne out of use in leisure and commercial application.

 

I wish you well with the new van, but I fear you are getting into the 5 P's territory with the whole thing now.

 

 

Please explain the point re 5Ps? Don't follow....

[Deffheads]

The Escapist

You must have your new van by now, Just go and enjoy it without over thinking what you might need. I'm sure you will cope initially with a standard set up for a while,and then fit your desired extras as needed.

 

[TheEscapist]

Deffheads - 2019-03-20 7:39 PM

 

The Escapist

You must have your new van by now, Just go and enjoy it without over thinking what you might need. I'm sure you will cope initially with a standard set up for a while,and then fit your desired extras as needed.

 

No, it just arrived at the dealer yesterday and I’m trying to get all I need done before I go off traveling for the summer,

[TheEscapist]

All sorted on the solar panels. Had a good chat with Photonic Universe and PV Logic and both impresses but PV Logic sin for me for guarantee of 20 years. I’m working with the dealer to get maximum number of panels to fit on the roof.

 

Moving to batteries.

 

My motorhome comes with 2 x 80ah leisure batteries as standard and I asked to fit a third same brand battery.

 

However, Im thinking of noting the bullet and trading in the gel batteries and fitting lithium batteries as they seem more efficient and over long term worth the outlay plus they are lighter.

 

Does anyone know how much greater capacity and performance I would achieve fitting 3 x lithium batteries of similar size (I guess I need to stick to same physical size) over the existing 80ah gel batteries? Ie. what size lithium battery fits in the same space as an 80ah gel battery?

 

Then with a bank of lithium batteries what is the increased charging, discharging, longevity etc and do I need any other system adaptation to use lithium over gel?

 

Thanks!

 

Paul

[globebuster]

Glad my information was useful - pity you didn't acknowledge the fact, I could have sorted you a good trade deal with either of those suppliers.

Still never mind, what's a few hundred quid in the grand scheme of things.

 

With regard to lithium batteries - I'm sure our resident expert will give his view, and it's worth taking on board his comments. He's done a great job for all of us on this forum, and I'm sure Allan will be happy to help.

[TheEscapist]

globebuster - 2019-03-21 11:34 PM

 

Glad my information was useful - pity you didn't acknowledge the fact, I could have sorted you a good trade deal with either of those suppliers.

Still never mind, what's a few hundred quid in the grand scheme of things.

 

With regard to lithium batteries - I'm sure our resident expert will give his view, and it's worth taking on board his comments. He's done a great job for all of us on this forum, and I'm sure Allan will be happy to help.

 

Globebuster, your help was much apprecisted. I think you can see I’m always grateful to everyone here and if you don’t get a personal thank you each time please don’t take it to heart.

 

Thanks

 

Paul

[aandncaravan]

I don't know the expert Globebuster refers to, I am no Lithium expert, only looked at half a dozen Lithium installed systems.

I also have to add that I declined to fix pretty much all of them because the implementation was so flawed that they were never going to give either of their best or be reliable.

 

 

Much is made of the Faster charging, and they can charge very fast, but why do the fitters then fit low power charging systems?

A 25 amp mains charger is going to charge at 25amps, not the '100 amps' charge rate the Lithium marketing oversells.

 

 

One big 'motorhome specialist' retailer is currently marketing 100Ah Lithiums and saying 'all you need to do to gain all the benefits' is fit a 30amp Sterling B2B!!!

No need to upgrade the Solar to Lithium optimised charging, no need to fit a 100Amp 230v mains Lithium optimised charger. Just fit a poor quality, low power 30amp B2B.

Priceless.

 

 

The best I can suggest is you start with our Lithium page, which has recently been updated, then do your own research : http://www.aandncaravanservices.co.uk/lithium-batteries.php

 

Bear in mind that about 95% of what is out there is marketing based or from someone with an interest in you buying the product.

 

Whatever you do, don't overlook the safety risk. Lithium is a highly flammable, high energy material that burns with a ferocity and temperature that vaporises metal. A 200Ah battery bank is a LOT of Lithium, a lot more than the few grams in the Samsung batteries that caught fire.

 

While we say an AGM battery is more prone to Thermal Runaway and a fire risk, it is slow to burn with much lower temperatures. As would be a typical LPG fire caused by a gas leak.

A Lithium fire goes from zero to Inferno in seconds.

 

I would suggest that isn't the ideal for a motorhome that already has much flammability already built in.

 

 

[Derek Uzzell]

The lithium-battery-related observations on this real-world-motorcaravanning blog may also be worth reading.

 

https://rvblog.co.uk/european-motorhome-tour/the-pros-and-cons-of-lithium-batteries-for-motorhomes/

[globebuster]

I don’t expect a personal thank you from anyone.

I think you really haven’t planned your project too well and appear to do limited research and hope others will reinforce your views - but please don’t take these comments to heart??

[TheEscapist]

globebuster - 2019-03-22 9:04 PM

 

I don’t expect a personal thank you from anyone.

I think you really haven’t planned your project too well and appear to do limited research and hope others will reinforce your views - but please don’t take these comments to heart??

 

We’re all different and move at different speeds. This is the project. Life is too short for me for any longer planning. When the finished article is driven away I’ll share photos and comments. I’m sure all will work out just fine. It’s only by challenging ourselves we bring out the best.

[mikefitz]

All the lithium batteries sold for the leisure market are based on Lithium Phosphate Cells. Each cell has a nominal voltage of around 3.2 volts so 4 cells are connected in series to give a nominal 12.8 volts.

There are only a few companies producing these cells ( in China) and the cells themselves can be purchased from the European distributor for around £110 for a single 100Ah cell.

The chemistry is very safe, unlike lithium ion, and the cells do not suffer from thermal runaway.

 

Unlike lead acid cells that self balance, so each cell is charged correctly, the lithium cells need active electronic circuits to 'look after 'each cell and ensure its not over or under charged. These battery management circuits, BMS, are often incorporated in the battery case.

 

The charging of Lithium batteries is fairly easy, charge at a rate up to 1C amps ( 100 amps for a 100Ah battery), or the limit introduced by the BMS. When you reach the recommended end charge voltage, around 14.4 volts, stop charging and disconnect the charger or drop to a low float voltage.

When using the battery the voltage will stay very constant even with high load, but when nearing the last the last few percent of capacity the voltage will fall rapidly. The BMS and any protective circuits must intervene and disconnect the battery. A terminal problem will occur if this is not done. Since the cells will have differing amounts of stored energy, a 'fully empty cell' will become reversed polarity and the energy from the other cells will destroy it, and often, in turn, themselves.

 

A further fact often overlooked by the marketing hype or even the built in management system, is that the battery must not be charged at a temperature less than 0 degrees C, it can be use to power systems but not be charged.

 

When installed in a motorhome all the charging systems must be designed to charge correctly and terminate charge at the recommended voltage, any conditioning , equalisation, high float voltage and temperature compensation must be inhibited .

 

As far as taking energy from the battery is concerned, subject to not exceeding the current limit, ( that will be very high), its crucial not to exceed the low voltage limit.

 

Whilst the marketing may suggest that the management system built into the battery will look after things, its prudent to incorporate additional sensing circuits and protective relays that look after the complete system. The better designed chargers, mains, solar and alternator derived, can be interfaced easily into the protective system.

 

Its my view that when using Lithium batteries, the complete 12v system needs to be fully compatible with the Lithium batteries, it need a complete system design from the start. Its very unlikely systems usually found in motorhomes will be able to successfully handle Lithium batteries as 'drop in ' replacements for lead acid.

 

Companies like Victron can supply every thing one would need for implementing a successful Lithium system.

Votronic are another company that suply systems that readily interface to Lithium with the Votronic Triple Series, this combines alternator, solar and mains charging in one unit. It has control interfacing that is easily connected to the battery BMS ( if applicable ) and to additional protective circuits and relays.

 

Anyone considering Lithium batteries should approach a installer or supplier that can offer a complete system that also incorporates a further layer of protection over the built in battery BMS.

 

Mike

 

 

[spirou]

In my view the cold charging is the biggest problem and argument against lithium in a motorhome. At least for those of us who live in places where temps regularly go below freezing. Just btw... e-bike manufacturers place the low temp charging cutoff at 5°C, so even higher.

 

Basically, I'd need to keep the heating on constantly from November to April to avoid a situation where someone starts charging a cold battery inadvertently. OK, I can have a BMS/solar reg that will hopefully prevent that situation but it seems to be a scenario that is prone to screw ups. It's why I like the idea of a removable lithium system recently posted on victron blog https://www.victronenergy.com/blog/2019/03/20/bigger-batteries-more-ah-needed/

[TheEscapist]

mikefitz - 2019-03-22 11:39 PM

 

All the lithium batteries sold for the leisure market are based on Lithium Phosphate Cells. Each cell has a nominal voltage of around 3.2 volts so 4 cells are connected in series to give a nominal 12.8 volts.

There are only a few companies producing these cells ( in China) and the cells themselves can be purchased from the European distributor for around £110 for a single 100Ah cell.

The chemistry is very safe, unlike lithium ion, and the cells do not suffer from thermal runaway.

 

Unlike lead acid cells that self balance, so each cell is charged correctly, the lithium cells need active electronic circuits to 'look after 'each cell and ensure its not over or under charged. These battery management circuits, BMS, are often incorporated in the battery case.

 

The charging of Lithium batteries is fairly easy, charge at a rate up to 1C amps ( 100 amps for a 100Ah battery), or the limit introduced by the BMS. When you reach the recommended end charge voltage, around 14.4 volts, stop charging and disconnect the charger or drop to a low float voltage.

When using the battery the voltage will stay very constant even with high load, but when nearing the last the last few percent of capacity the voltage will fall rapidly. The BMS and any protective circuits must intervene and disconnect the battery. A terminal problem will occur if this is not done. Since the cells will have differing amounts of stored energy, a 'fully empty cell' will become reversed polarity and the energy from the other cells will destroy it, and often, in turn, themselves.

 

A further fact often overlooked by the marketing hype or even the built in management system, is that the battery must not be charged at a temperature less than 0 degrees C, it can be use to power systems but not be charged.

 

When installed in a motorhome all the charging systems must be designed to charge correctly and terminate charge at the recommended voltage, any conditioning , equalisation, high float voltage and temperature compensation must be inhibited .

 

As far as taking energy from the battery is concerned, subject to not exceeding the current limit, ( that will be very high), its crucial not to exceed the low voltage limit.

 

Whilst the marketing may suggest that the management system built into the battery will look after things, its prudent to incorporate additional sensing circuits and protective relays that look after the complete system. The better designed chargers, mains, solar and alternator derived, can be interfaced easily into the protective system.

 

Its my view that when using Lithium batteries, the complete 12v system needs to be fully compatible with the Lithium batteries, it need a complete system design from the start. Its very unlikely systems usually found in motorhomes will be able to successfully handle Lithium batteries as 'drop in ' replacements for lead acid.

 

Companies like Victron can supply every thing one would need for implementing a successful Lithium system.

Votronic are another company that suply systems that readily interface to Lithium with the Votronic Triple Series, this combines alternator, solar and mains charging in one unit. It has control interfacing that is easily connected to the battery BMS ( if applicable ) and to additional protective circuits and relays.

 

Anyone considering Lithium batteries should approach a installer or supplier that can offer a complete system that also incorporates a further layer of protection over the built in battery BMS.

 

Mike

 

 

Very helpful. I'll stay with gel for now and watch lithoum technology develop.

[flyboyprowler]

From a practical point of view, we have just driven back from Spain using just Aires and the option battery set up supplied from Niesmann, two leisure, and one engine battery, has proved got be completely satisfactory, We have used the inverter for toast, hair dryer etc, and have also spent several days parked up, living off batteries, with no problem. I assume your Carthago has an inverter. Also, having after market panels fitted to a new van could have ramifications with your guarantee. Probably worth checking with the dealer!

[aandncaravan]

mikefitz - 2019-03-22 10:39 PM

 

All the lithium batteries sold for the leisure market are based on Lithium Phosphate Cells.

The chemistry is very safe, unlike lithium ion, and the cells do not suffer from thermal runaway.

 

Mike

 

 

Mike, Lithium Iron Phosphate are Lithium Ion batteries, just as Lithium Cobalt, Lithium Manganese and Lithium Nickel are.

Lithium Ion is the chemistry that they use, the different trace materials are used to bring out different characteristics.

Lithium Iron Phosphate are one of the safest of the group so far, at the expense of lower energy density over Lithium Cobalt, but I am certain I would not list it as 'very safe' in a motorhome environment.

 

If a Lithium Iron Phosphate (LiFePo4) battery is stressed it is subject to damage and becomes a fire risk. A motorhome with it's excessively wide temperature range (last year the Beast from the East brought -20 up to the summer record temperatures of close on 50 degrees in Portugal) plus high vibration, is not the ideal.

 

The marketing also pushes the very things that stress a Lithion Ion battery the most : High discharge currents, high charge currents, 100% fully discharged cycling, etc. Things, like connection to high power Inverter/chargers, are being 'sold' as the batteries 'strength' and they are being bought for that.

 

The motorhomes these units are being sold into is a highly alien environment to a Lithium, one like they have never experienced in mainstream use so far. The idea of a Lithium battery being asked to supply 100amps to an Inverter in 35 degree temperatures is frightening.

 

To me that translates to a higher fire risk. A much higher Fire risk.

 

 

With Lithium being such a high energy material, it will burn with a ferocity we have not seen often.

Even if the risk were low, the consequences of that would still be horrifying in the 'Tinder Box' of a motorhome.

 

 

Spirou, A 'Drop In' Lithium that could be removed does sound a good idea, but hard to achieve in a modern motorhome.

A Lead Acid battery is the Heart of the Sargent, Schaudt, etc power controller. The Lead battery is at the centre of all the chargers from Alternator, Solar and Mains, yet all these units are unsuited to a Lithium so a Lithium needs to completely bypass the existing wiring and have chargers of it's own that are optimised for Lithium.

 

Just look at you own installation and work out how you would connect it to the Schaudt distribution box, yet avoid it being charged by the Schaudt mains charger, Alternator and Solar and not lose any functionality.

Then imagine explaining to the next buyer what you did and explain what they need to do to revert back?

 

So just getting a Lithium into place safely and without losing existing functionality is a challenge. Setting it up so it can easily switch back to using a Lead battery in an emergency, is even more of a challenge.

You can imagine what it will do to the warranty?

 

 

[monique.hubrechtsgm]

Have also a look what Hymer now can provide. They combine a lead whit a lithium. Why they do?