Different Batteries - Same System Question

[marwin]

I currently have 2 x Trojan 27TMX 12V Batteries hooked up to my 2x150W Panels up top through a Tracer MPPT controller.
I want to have more power storage.

QUESTION ONE:
Can I just add more batteries in Parallel to the system and have more storage without doing anything else ?
(I understand it may take longer to charge them all

QUESTION TWO:
Can I mix and match batteries (brands etc). -- I found some Marine Batteries at Walmart (Maxx EverStart). My current batteries are flooded (I add water sometimes) - these batteries I am not sure need the water .. but I need to know .. can you mix and match battery brands (and in this case maybe types). or - do I need to find the exact same battery to add more and not confuse my controller.

Thanks any help on this.

[Mike90250]

No. ( following is for flooded lead acid batteries, generally the best bang for your buck)

Batteries in a bank (parallel or series) should be of the same make & model, preferably from the same batch.

The more closely matched they are, the more balanced the bank will stay. The more balanced they are, the less often you have to Equalize the batteries ( a slightly damaging overcharge to insure all the batteries are fully charged.)

My advice, which I believe will be the best economical, is to continue using the system as is, learning as much about how it behaves and maybe learn to manage loads more.
Batteries need to be fully charged within 48 hours of discharge, or they will begin to sulphate (slowly die) . Adding more batteries, without increasing your recharge capability, will only leave you with more dead batteries (manage your loads better, or get more charging).

When these batteries need to be replaced, you have a expense decision to make :
a) duplicate the system and plan on replacing batteries every year
b) grow the system - panels and batteries (150w PV per battery is a good average starting point)

Battery suggestion.
200ah 6V Golf Cart batteries. Made by the millions for golf carts, cheap, deep cycle. Wire 2 in series and you have a 200ah 12v bank. Add 2 more in parallel and you have a 400ah 12V bank (which needs 2 more PV's and maybe a new larger charge controller)

About the 300 - 500 watts of PV, you have a choice of expensive parts:
Expensive "12v" 150w panels and cheap charge controllers
or
Cheap 300w panels and expensive MPPT charge controller.

Beyond 500w, and the MPPT systems are more economical. That's going to be your choice to research while this batch of batteries lasts.

[marwin]

If I did buy another battery of the same make/model and realize that they must be charged - are two 150w panels enough to charge 3 of them ? The two batteries I have fill up fast and during the day - I wont drain them - but into the night with heavy computer use I can drain the two batteries I have before the sun comes up again. I was thinking just add one more battery in parallel and I should have more time … at the rate these two batteries charge - I don't think a third would be an issue.

[SunEagle]

If I did buy another battery of the same make/model and realize that they must be charged - are two 150w panels enough to charge 3 of them ? The two batteries I have fill up fast and during the day - I wont drain them - but into the night with heavy computer use I can drain the two batteries I have before the sun comes up again. I was thinking just add one more battery in parallel and I should have more time … at the rate these two batteries charge - I don't think a third would be an issue.

A good rule of thumb would be to have enough solar panel wattage to provide 1/10th the Ah rating of your battery system. I am guessing that 300 watts of panels and an MPPT CC can provide about 25 charging amps which would be good for a 250Ah battery system. A third battery may increase the Ah rating to more than what that 300 watts can properly charge which will end up killing of the weakest battery first.

[Mike90250]

What is the computer you are using, a desktop or a laptop ? Can you use more efficient modes with it? Are you running a 200w computer off a 2,000w inverter ?

[marwin]

I have two laptops - one does not use as much energy which is fine - but my Alienware for gaming uses a power brick 100-240w input - I have a 3000w inverter - the goal is to be able to game longer and the beefier laptop is a bit power hungry.

i can run it all day long in the sun - but it won’t last all night which is the goal.

[Mike90250]

You need to downsize your inverter to something in the 500w ballpark, and only energize the 3kw when you need that extra power. The inverter idling along likely consumes 50w on it's own, a smaller inverter will consume much less.

200w for 10 hours is 2kwh. A pair of group 27 batteries would store about 2.4kwh and only have 1.2kwh usable at the 50% threshold. Discharging to 50% will also shorten the life of the batteries.

300w of solar, well aimed, for 4 hours, could harvest 1200wh You have to be in a pretty special location to get a reliable 4 hours of good sun in the 3 worst months of the year.

I'm going to suggest you need about 700w of solar, a MPPT controller for the best harvest, and a 24V bank made of four 6v 200a golf cart batteries and a 500w 24V inverter. And 1 cloudy day kills the batteries unless you use a generator to recharge

[SunEagle]

I am still wondering how the internet system is being power for all that gaming.