In the interests of a lively mass debate there's polycrystalline & monocrystalline. The type which generally cover a significantly larger area per watt are a 3rd type - 'amorphous'. These are said to have better heat tolerance, but for vehicle based set ups their extra size has relegated them to 3rd place. Poly is a bit cheaper than mono, but my experience is that mono is a bit more efficient.
http://www.solarchoice.net.au/blog/w...ous-thin-film/
I don't know anything about the roll up panels other than they are incredibly expensive. $1800+ for 72w. At those sort of prices I'd rather consider one of the Efoy fuel cells
http://www.redarc.com.au/products/ca...-solar-panels/
http://www.eco-camper.com/component/...fuel-cells.htm
The system I have on the Patrol is part fixed & part 'mobile'. 1 x 125w mounted on the roof of the cab & 300w loose. 360ah AGM batteries & a Redarc bcdc1240 (40 amp version of the Redarc unit I referred to earlier). As I said this is a system still to be proven. I have attempted to set it up for touring, so that the portable panels will only need to be set up if camped for a couple of nights plus, but once set up should be good for an indefinite stay. The battery capacity I hope will give me a buffer against bad weather for up to a week. I do think too much is better than too little.
I acknowledge that I have no experience of systems set up for short term camps as I imagine may be more common among 4wd'ers. I'll be interested to hear if there are issues I haven't considered that are relevant to this sort of use.
Cuppa
2006 4.2TDi ex-Telstra Remote area Camper. Patrol Sold after 11 years of ownership Replaced with 2006 OKA NT Expedition Truck. Cummins, Allison & lots of goodies
A Nomadic Life (Blog)
I'm keen to know this too. As I have this isolator in my troll with a Supercharge D70ZZ 100AH secondary battery. I currently have a 190w solar panel setup, I need to change the cheap regulator to a 20A MPPT type. But now I have just purchased an 80L Combi Engel. A bit concerned on how this big Engel will last on the battery with the solar panels.
I may need ot start another thread I think as I have more questions I need answers too.
Sorry for the thread steal...
Yes it is different, it is a bit smarter than the SBi12 in that it
allows for different charging voltages of different types of
batteries. ie. if your 65ah battery is an AGM it needs a different
charging regime to your wet starter battery. (But it will survive if you stick with what you have)
More importantly it is also a smart
charger which will ensure you have the best chance of fully charging
your 65ah battery when driving (dependent upon how long you drive for). You could
virtually drive for ever using the SBi12 & still not charge the 65ah
above 80%. This is fine for a starter battery, but when you are
relying on having the full capacity to make your fridge use last
longer when you get to camp starting at 80% & not taking it below say
50% means you only have 30%, or about 20ah to play with.
I have two separate systems in our bus, one uses an Sbi24 (24v
version), actually it's a slightly different 2 way version the SBi4D,
which allows the solar connected to the house batteries to charge the
starter batteries, as well as charging the house batteries from the
alternator. (Readily available by special order, but not generally advertised).
In this case though both sets of batteries are AGM's (so have the same charging needs) & the
solar 'tops up' the batteries through the multi stage charger
incorporated in the solar reg. This works ok, because I have plenty of solar capacity for a lightly used system, your proposed system would be more marginal & thus not have the same degree of 'flexibility'. I used to have wet starters but they
didn't last as long due to being overcharged from the solar. The AGM's
survived this regime ok however.
Bottom line is that whilst the SBi12 will work in your situation, it likely wont work well enough, & without doubt can be improved upon. Horses for courses. Depends on the condition of the wallet. For $200 you could buy a panel with a cheap regulator attached & give it a try. If it suits...... great, if not you can throw away the regulator, sell the SBi12 & buy/install a BCDC1220.
Cuppa
Last edited by Cuppa; 26th November 2012 at 09:31 PM.
2006 4.2TDi ex-Telstra Remote area Camper. Patrol Sold after 11 years of ownership Replaced with 2006 OKA NT Expedition Truck. Cummins, Allison & lots of goodies
A Nomadic Life (Blog)
Sorry to jump in again. This last comment i'm interested to know more. I have 190w panel setup, which does have a cheap regulator, and I also do have a SBi12 with a 100AH deep cycle. So, I can run the panels without the regulator? If I use a BCDC1220? My panels are portable too BTW? I don't want to go out and spent $90'ish for a MPPT 20A regulator when I don't need too.
thanks.
Ummm I wouldn't advise using the panels without a regulator.
I have an an apology to make. The BCDC1220 is NOT a solar regulator (it has no solar regulation function) I thought it was the same as my BCDC1240 which is an MPPT solar reg. The lower amperage model that IS an MPPT solar regulator, DC to DC smart charger and battery isolator in one is the BCDC1225 - a 25 amp version of what I have. Sorry for causing any confusion folks.
http://www.ebay.com.au/itm/REDARC-BC...ht_1784wt_1348
http://www.redarc.com.au/images/uplo...d_02052012.pdf
http://www.redarc.com.au/images/uplo...ion_Manual.pdf
Cuppa
2006 4.2TDi ex-Telstra Remote area Camper. Patrol Sold after 11 years of ownership Replaced with 2006 OKA NT Expedition Truck. Cummins, Allison & lots of goodies
A Nomadic Life (Blog)
Just made this thread Sticky as I think that it will be very helpful to everyone for future reference.
Can everyone please continue adding to it and especially after the fishing get together trip, when this topic is discussed around the campfire...................I have an ulterior motive as well, I need a solar panel for my fridge...lol
If any members require assistance in anything regarding this forum, just let me know via a PM and I will help you in any way that I can.
Thanks cuppa for the info. At that price for the BCDC1225, I think i just buy a decent MPPT 20A reg for my panels. I have a front locker I'm supposed to be saving for.
Hi mudski,
I agree that in your situation that is probably the best solution for short/weekend camps. Having the BCDC1225 would extend your time a bit, but as your solar will give you around 55ah per day & your fridge will use up to around 60ah per day you can easily last a long weekend (& often more) without taking your battery down to damaging levels (provided the sun shines of course). In those circumstances the extra cost of the BCDC is not economic.
For anyone interested the rule of thumb I use for calculating daily output of panels is their wattage divided by their nominal voltage & multiplied by 70%. This gives the hourly output. I then use an average of 5 sun hours per day to calculate daily output. So, for example using a 100w panel @ 12v. 100 divided by 12 = 8.3ah. 8.3x70%=5.8ah (hourly output). 5.8ah x 5 =29.1ah per day. Close enough to 30ah per day for a rule of thumb.
Why multiply by 70%? ..... This allows for the losses associated with the less than optimum positioning of the panels. ie. mounted on the roof of the vehicle. If portable panels are used & the owner is conscientious enough to angle them correctly & move them to face the sun every hour or so throughout the day output can be increased a bit above that 70%.
Sun hours - the average number of sun hours varies according to location & time of year. I have found 5 to be a reasonable average. Up north they could go as high as 7 in summer, & as low as 3 down south in winter.
I should acknowledge that these figures do not come from my head, but are digested from the very easy to read books written by Collyn Rivers whom I have known personally for a number of years.
Cuppa
2006 4.2TDi ex-Telstra Remote area Camper. Patrol Sold after 11 years of ownership Replaced with 2006 OKA NT Expedition Truck. Cummins, Allison & lots of goodies
A Nomadic Life (Blog)