Thoughts on a new install

[Samsvan]

After reading through dozens of really useful and informative posts I have finally signed up in hope of getting some feedback. Like many first time posters on here I am brand new to solar but have been researching and reading extensively in order to get a better understanding of how everything works and what will be the best fit for my setup.

I am looking to do a self conversion on a Ford transit panel van in the UK later in the year and have narrowed down the basics of my solar setup as follows:

I have calculated my needs to be ~60ah a day and originally wanted to have 3 days backup (reason for choosing 2 x 190ah batteries below) in case of miserable weather that wouldn't provide the best charging conditions. I will be traveling around Europe for at least a year and don't want to be staying at campsites to help keep costs down. With this in mind I have decided not to have a plug in for mains but will include a split charger. After reading many posts, blogs etc, it appears that many people don't recommend having 12v batteries in parallel but do promote the use of 6v in series to get a 12v bank, that is why I am torn between the two options below, even if it does mean having a considerably smaller bank.

I don't think my needs are too excessive. Waeco fridge, led lights, water pump, charger for laptop, heater, electronic keyboard and a few usb chargers for phone etc.

1 x 300W Solar Pannel

http://www.bimblesolar.com/solarworld300w

2 x Trojan T105 in series or 2 x 12v Explorer 190ah in parallel

https://www.tayna.co.uk/T-105-Trojan-Battery-Deep-Cycle-T105-P7253.html

http://www.alpha-batteries.co.uk/leisure-batteries/190-ah-xplorer-leisure-battery/

1 x MorningStar ProStar - PS-MPPT-25M

http://www.morningstarcorp.com/products/prostar-mppt/

1 x 300w Pure Sine Inverter

https://www.amazon.co.uk/d/Car-Vehicle-Power-Inverters/300W-pure-power-inverter-convert/B00QGRSEBS/ref=sr_1_1?ie=UTF8&qid=1492726520&sr=8-1&keywords=pure+sine+inverter+300w

Any thoughts / feedback from the gurus or anyone for that matter, would be greatly appreciated. I guess my main concern is the sizing of the system and ensuring that I have enough battery power for my needs, especially choosing between the 6v or 12v options even if it does mean a smaller bank.

Thanks,
Sam

[jflorey2]

Any thoughts / feedback from the gurus or anyone for that matter, would be greatly appreciated. I guess my main concern is the sizing of the system and ensuring that I have enough battery power for my needs, especially choosing between the 6v or 12v options even if it does mean a smaller bank.

2 6V in series. Cheaper overall. If you need more I'd go with 4 6V (series/parallel.)

[littleharbor]

2 series wired 6 volt 220 amp hour batteries have the same amount of power as 2 12 volt 110 amp hour batteries in parallel , 220 amp hours @ 12 volts. AND they occupy the same amount of space. You are better off with a single string battery bank. less connections, less cells to check and fill and with 6 volt golf cart batteries you will be getting a true deep cycle battery as opposed to the many so called "RV/marine deep cycle batteries.

[Samsvan]

Thanks for the feedback. Am I right in thinking the 25amp prostar will be sufficient for the panel I have chosen and given I am using a 12v bank?

[littleharbor]

Specs say up to 350 watts at 12 volt.

[sensij]

Thanks for the feedback. Am I right in thinking the 25amp prostar will be sufficient for the panel I have chosen and given I am using a 12v bank?

Depending on where you are located and how you are mounting it, you might find 300 W is underpowered. Your batteries will appreciate it if you can get your CC up to its 25 A max output, but you'll need another panel (or a larger one) to do that with any regularity.

The data sheet estimates that you'd need 350 W to get to 25 A once you account for losses, but even that is probably best case. You can put more PV power than that on the CC, it will self-limit to the rated 25 A output.

From the data sheet:

*Input power can exceed Nominal Operating Power. Controller will limit and provide its rated continuous maximum output current into batteries."

[Samsvan]

Depending on where you are located and how you are mounting it, you might find 300 W is underpowered. Your batteries will appreciate it if you can get your CC up to its 25 A max output, but you'll need another panel (or a larger one) to do that with any regularity.

The data sheet estimates that you'd need 350 W to get to 25 A once you account for losses, but even that is probably best case. You can put more PV power than that on the CC, it will self-limit to the rated 25 A output.

From the data sheet:

Ensuring I have enough power to fully charge the batteries is part of my concern. I don't intend on having a mains hookup in the van as I am hoping to be out in the wild for the vast majority of time. With this in mind I need to ensure I can get the bank completely charged on solar alone.....