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Hello, I'm a newbie to solar and forums in general but have a few questions about the Harbor Freight solar kits. I purchased one 45 watt kit a few weeks ago and purchased a hybrid marine battery just to play around and experiment with.
Well, I’m hooked now and was thinking about purchasing 3 more HF kits for a total of 180 watts and was looking to purchase two 6 volt golf cart batteries in series for 215 amp hours.
Is 180 watts enough to recharge these two batteries for occasional non-daily use or do I need more panel watts?
I also have questions like....
1.) Can I use all 4 controllers that come with the kits at the same time or do I need to buy one larger capacity controller?
2.) Do I need to buy an additional piece of hardware to hook all 4 kits up together or will I have everything that I will need in order to do that?
Hey T.F. welcome to the forum!
For starters, to answer "is 180 watts enough" oh heck yea. But it's more important to ask, how more are you realistically going to use. Time to get out the calculator and read everything you can here about doing the math on how much power you are REALLY making and how much you are REALLY using.
Also, as far as hooking it all together. Search and read everything you can on buss bars and combiners boxes. Make sure to search through the photos. Don't worry, this is easy!
Thanks for the reply Ray. In the myriad of stuff I've been reading online I thought I had seen something that said the total amps put into your batteries from the panels should be at least 10-12% of the total battery bank amp hours. So in this case, 4 HF solar kits would put out about 12 amps but that is only about 6% of the 215 amp hours that the batteries would hold so I wanted to make sure that I don't get "too much" battery for "too little" panel amp output.
Hope I made sense there.
You are correct you really want to have a ratio of at least 10% especially if you are going to be puling power off of them as well. This is mainly to ensure you can get the batteries to absorption level in a reasonable amount of time and not go to low that you destroy the batteries. Can you run with less yes but it will take longer to recharge the batteries and if you are also draining them at the same time even longer to get them back to a full charge. Just a way to make the battery life as long as possible since replacing them can get expensive if you have to do it often. Also the disruption in your power usage is never fun.
Thanks for confirming what I thought that I had read recently.
Welcome to the forum Titanflopper! I got hooked on one kit and a marine deep cycle battery as well and hope to get more panels soon and upgrade to better batteries. Its addicting but its a good addiction.
Thanks Jeremiah, yes, so far I'm loving it!
Greetings Titanflopper. What does that nickname mean btw?
"So in this case, 4 HF solar kits would put out about 12 amps"
Hate to say it but you might get 2+ amps out of each kit good weather provided. You could parallel the kits into a combiner box then feed one good 15-20 amp controller with the proper stranded awg. Try to keep the wire run from panels-box to controller short as possible.
Titanflopper meaning? Not too much really. I am a TN Titan fan (live in Nashville) and I needed a username for an online poker-for-fun account so I just made the name up actually.
Thanks for the advice. I'm about a month away from purchasing any more panels but after we had a power outtage yesterday for a few hours I decided real quick that my little 45 watt kit and 57 ah battery were not going to help me very much so I thought of moving up to the next level without spending too much money out of pocket.
My 2 cents... You mentioned getting 3 additional HF kits, which would run you about $450. I would say go for 2 DM 145 panels $320, when they are back in stock, and a BZ MPPT250 charge controller for $130. Bigger bang for your buck?
Yea, Mark is right. We'll help you put it all together, the combination of your existing HF Kit and the two 145 watt panels would be a much better investment.
Thanks guys, I was just looking at those this morning and I was thinking the same thing! I didn’t see where you could order them and put them on backorder but it definitely sounds like a better use of my money. Heck, I'm thinking about ordering 2 sets (4 panels). How will I know when those are back in stock?
We will have them back in mid August, I'll send you an email a day or so ahead of time and then the day the link goes live.
Just make sure you bookmark the link, they go fast > http://astore.amazon.com/newworldsolar-20/detail/B007VPQP5Q
4 145 watt panels? You'll be rockin!