Lithium Battery

Very good question.

Weight & volume Peter, weight & volume. But you do pay for that benefit!

They are 2 reasons, but the OP's reasons may be different.
I am still using AGMs in our OKA and see no reason to change to anything else, but I am building another OKA MH and that will get Li batteries for weight (not volume) and power delivery reasons.
Cheers,
Peter
OKA196 motorhome

Yes, you did ask a good question Pete.
And I know that you have had good performance from your AGM's. I just couldn't resist.
I had satisfaction from my AGM's in the Troopy but it was Lithium in the Sprinter for weight & space considerations. Certainly not for high current delivery.

Macca's two-for-one expression is a common rule of thumb. It decrees that you need double the solar watts for the Ah that you are pulling from your battery.

I see almost no relationship between battery capacity and solar capacity.
Recharge capacity (from whatever source) needs to exceed energy daily usage and daily energy usage has very little relationship to battery capacity.
Batteries provide energy when the charge source is absent or inadequate.
Cheers,
Peter
OKA196 motorhome

Hi Pete,

Your comment regarding recharging capacity is very true. However, from what I understand, the reason the “experts” recommend the two times watts vs amps, is to ensure you can recharge your batteries to “full” capacity relatively quickly. Now, whilst I am not sure of their full reasoning, it makes sense that in limited sunlight, you would want to take advantage of charging as quickly as possible, to ensure your batteries reach full charge before losing the best available sunlight. “Making hay while the sun shines” so to speak.

Given that depending on where you are in the country and the time of year, you really only get around 6 hours of “optimum” sunlight for charging at the highest/quickest rate, it makes sense to want to charge quickly. Charging rate is dependent on having your solar panels at the optimal angle to the sun and “chasing” it. If, as with most caravans and motorhomes with fixed roof mounted panels, it is not possible to get the optimal angle to the sun, the more solar capacity you have the better.

Of course many people get away with less solar capacity than twice battery amps, but it does not take long for batteries to go “flat” if you are unable to get them up to full charge every time. I know that I would rather have my batteries back to full charge as soon as possible, instead of late in the day.

Macca.

So a 9KG gas cylinder lasted you 1.4 weeks? Man that is a lot of gas.
My fridge will last about a month on a 9Kg cylinder , and I only use that if free camping, 240V at other times.
grandmother quote."I have told you a million times not to exaggerate"

Hi Rangiephil,

LPG usage can vary greatly depending on a number of things. If you are only running a small fridge in a cool dry climate, I dare say that you could get quite a lot more days out of a 9 or 8.5 Kg LPG bottle than what you are currently getting. If you have a large absorption fridge in a hot humid climate, and using the LPG for other things like cooking, and hot water, depending on how many showers you have, it could be a lot less. Many people on this and other forums have quoted between two and three weeks out of a 9 kg LPG bottle for off grid camping.

So as someone else has said elsewhere on this forum, horses for courses.

Macca,

@ Rangiephil

Yep!
The original Dometic 175l 3-way went through a 9kg cylinder every 10 days.
It now lasts 3 months. Cooking only.
Diesel air and water heating.


No exaggeration necessary.