Greetings from WNC

[Bodo]

Installing our initial solar setup this spring. Starting with 4.2kw of Axitec panels (360W), Sol-Ark 8k inverter/charger with 8 Trojan 220ah 6v batteries to store those electrons.
We're in rural Western NC and the power grid here is not dependable at best. Looking forward to keeping the genset in the barn for a while! More panels and batteries in the next year. want to get 10kw and double the battery bank.

Looking forward to sharing our build and learning as we go.

[SunEagle]

Hello Bodo and welcome to Solar Panel Talk

I presume you are building a 48V battery system considering the panel wattage.

Just a note about battery systems. There is no easy way of expanding an existing system except to replace all of the batteries at the same time because old and new batteries don't play well together. So if those 8 Trojans don't work out for your loads you might have to replace all of them instead of just adding to them.

[Bodo]

Yeah we know. Budget is what it is. It really depends on the condition of the batteries, doesn't it? If they're lightly used we should be OK with adding more batteries within a year or so, right? If not, we'll sell them and do something else.

[SunEagle]

Yeah we know. Budget is what it is. It really depends on the condition of the batteries, doesn't it? If they're lightly used we should be OK with adding more batteries within a year or so, right? If not, we'll sell them and do something else.

Old (even six months) and new batteries are like apples. The bad ones will hurt the new ones much quicker then expected. Which means the older batteries will end up lowering the performance of the newer ones and you will never get the expected cycles out of them. Just a heads up because you will probably need to replace all of the batteries in a shorter time frame then you have calculated.