…… Need best beginner's guide to solar panels and batteries

[JasmineAndLace]

Thank you, Loup, for all your explanations and patience. You make it almost understandable for this 70+ year old female. My biggest concern is for our well and pressure system--would love to have something for the house and deep freeze as well but the water system is the main concern.

 

[Dennis Olson]

If you want to power your entire home, expect to pay in excess of $30,000 for a solar system. And don not try to install that yourself.

 

[Kennori]

You could hire a Solar installer electrician. They would step in and using your husbands plans and equipment probably make a viable system and even eliminate any problems and beef it up to industry standards. Let the pro's do it, I learned the hard way.

 

[Jackpine Savage]

Safety first. As an example with my small system I have the combiner box in the roof with DC rated circuit breakers (very important) for the solar strings. That goes into the charge controller. And then I have DC rated circuit breakers on the positive and negative leads out of the charge controller going to the positive and negative battery busses. And then I also have a 300 amp rated battery switch coming off the battery bank going to the positive buss.

And then on the battery bank itself I have quick acting fuses on the outputs going to the battery busses and I have the negative buss bonded to a ground rod. If I was running a 36 volt or 48 volt system I would also bond the solar panel frames to the ground bar in the solar combiner and then to top it off I have a lightening arrester mounted to the solar combiner.

I mixed and matched components over time as I could afford them although if I was going to do it over I’d buy the complete packaged from a reputable dealer including the batteries and then have it dropped shipped and I’d still do the install. That way the dealer sizes the whole package and components based on the size of the system two, three or four KW etc.

Thanks! Are you running a 12v or 24v system? If it's 24 what are you using for a 12v converter? Any problems with RFI and your ham equipment?

I think I am going to give a couple of the dealers a call and see what they can do.

 

[Jackpine Savage]

The set up in this video looks like where I want to be. 2000w inverter, generator input, nice monitoring. Run time 8:54.

View: https://www.youtube.com/watch?v=Ol-ZnUqLD_w

 

[Hfcomms]

Thanks! Are you running a 12v or 24v system? If it's 24 what are you using for a 12v converter? Any problems with RFI and your ham equipment?

I think I am going to give a couple of the dealers a call and see what they can do.

Mine is just 12 volt as I don’t need to run an inverter much and it’s just a 1KW system as that is all I need. All my radio gear is 12 volt of course and that was the main reason for the system. My water pump and LED lighting is all 12 volt as well so it just made sense.

If I wanted to go 24 or 36 volt for a larger system you can still tap your batteries for 12 volt and avoid the hassles for a converter. Right now I use Trojan T-105 batteries which are only six volt but I run those in series for 12 volt and then in parallel to add capacity. You could run two 12 volt sets in series for 24 volt or three for 36 volt but you could tap just one set for 12 volt and use a separate battery bus for 12 volt only I would imagine.

Loup or someone else can jump in here if for some reason that is a bad idea but it would avoid the losses of a DC to DC converter. As far as RFI goes I eliminated those problems with a goodly amount of torroids on the coaxes and power inputs. I get a bit if hash when I run the battery charger and it raises the noise floor on HF a bit but it’s not bad.

 

[hiwall]

If I wanted to go 24 or 36 volt for a larger system you can still tap your batteries for 12 volt and avoid the hassles for a converter. Right now I use Trojan T-105 batteries which are only six volt but I run those in series for 12 volt and then in parallel to add capacity. You could run two 12 volt sets in series for 24 volt or three for 36 volt but you could tap just one set for 12 volt and use a separate battery bus for 12 volt only I would imagine.

No, I would not recommend tapping just one or two batteries from a larger bank of batteries. Doing so will draw the tapped battery(s) down and your charging system will likely not properly compensate for the one or two low batteries. It will lead to issues.

 

[Hfcomms]

No, I would not recommend tapping just one or two batteries from a larger bank of batteries. Doing so will draw the tapped battery(s) down and your charging system will likely not properly compensate for the one or two low batteries. It will lead to issues.

Agree in principle but I would have to add the obligatory 'it depends' statement as well.

If someone was just tapping one of the banks to run a string of 12 volt LED lighting for example that only draws a few watts for a couple of hours a night the amount your pulling out would be inconsequential.

For me if I wanted to go totally off grid I'd probably do the 24V or 36V system with the inverter for AC and then I'd use a DC to DC converter in that case as I have a lot of 12 volt stuff. Right now since I already run so much stuff off 12 volt I don't need my inverter very much and if I need a lot of AC during an outage I just fire up the generator. Everyone's situation is different.

I'd like at some point to move deeper into the bush and at that point I'll be totally off grid and will redo everything.

 

[hiwall]

Agree in principle but I would have to add the obligatory 'it depends' statement as well.

If someone was just tapping one of the banks to run a string of 12 volt LED lighting for example that only draws a few watts for a couple of hours a night the amount your pulling out would be inconsequential.

For me if I wanted to go totally off grid I'd probably do the 24V or 36V system with the inverter for AC and then I'd use a DC to DC converter in that case as I have a lot of 12 volt stuff. Right now since I already run so much stuff off 12 volt I don't need my inverter very much and if I need a lot of AC during an outage I just fire up the generator. Everyone's situation is different.

I'd like at some point to move deeper into the bush and at that point I'll be totally off grid and will redo everything.

The reason I replied was because I did that exact thing. My battery box was getting warm inside even with several vents. So I installed a small 12v recycled computer fan to aid heat dispersal. Very little draw. The fan worked fine but one day I saw my overall battery bank voltage was low. So I checked all the batteries individually. The two I used to run the fan were lower than the rest and dragged the whole bank down.
I then charged the two batteries separately until full and had no problems since. I changed to use a small transformer on the exhaust fan so it would draw from the bank as a whole.
Not a big deal and others might have had no problems. But just a word of caution.