DOE issuing guidelines on sale of solar panels

[Paul 55,116]

 

 

Gaining a few percent "efficiency" with MPPT is meaningless if the added complexity means failure is going to kill your batteries, or short out your panels years before their predicted failure date.

 

When I went from my MorningStar PWM controller, to my Midnite Solar "Kid" MPPT controller, I noticed a significant increase in output from the panels. I cannot say what percentage increase in output it was. But, it is definitely more than a "few". It allows more amperes to go to the batteries than a PWM controller does. 

 

Another positive about running an MPPT controller is, array voltage no longer has to match battery voltage. 

[thebob 18,260]

When I went from my MorningStar PWM controller, to my Midnite Solar "Kid" MPPT controller, I noticed a significant increase in output from the panels. I cannot say what percentage increase in output it was. But, it is definitely more than a "few". It allows more amperes to go to the batteries than a PWM controller does.    Another positive about running an MPPT controller is, array voltage no longer has to match battery voltage. 

 

 

But you've had battery failures that have totally removed the advantage. Were they controller related? I'd be more interested in a controller that balances batteries in a bank, and cells in a battery, than anything more complex than a plain old through hole tech controller that I could repair myself.

 

Batteries are the problem, panels themselves are quite robust. I'd prefer multiple arrays, going to multiple charge controllers to multiple battery banks with multiple inverters. All the electronics in nice big fan cabinets and separate the heat sinked power transistors from the capacitors, which should be large screw in high temp types.

 

This is what a battery bank should look like, so you can see what is going on.

 

https://www.cdtechno.com/product/vla/vla.html

 

 

Edited July 21, 2015 by thebob

[Paul 55,116]

Were they controller related?

 

No. It was battery issues. I purchased used batteries. The sole reason for doing so, was because I got them so cheaply. There again, you pay for what you get. But, I figured they would last only a year anyway. However, I got almost two years out of them. So, no complaints, really. 

 

 

 

 

I'd be more interested in a controller that balances batteries in a bank, and cells in a battery, than anything more complex than a plain old through hole tech controller that I could repair myself.

 

My "Kid" has an option to equalize batteries. Not to mention, I was running 12vdc batteries in parallel. I should have run them in series, or went with 2v or 6v batteries in series. It's easier for them to be equalized if they are in series, than in parallel. Not to mention, running more than two strings, three at the very most in parallel, is just asking for trouble. 

 

When I replace the batteries, I will go with 6v golf cart batteries, most likely. I am still researching the best place to buy them from. 

 

 

 

 

I'd prefer multiple arrays, going to multiple charge controllers to multiple battery banks with multiple inverters.

 

Modern MPPT controllers, including my "Kid", have options for "Follow Me", which will sync all controllers to run as a single unit. The master will determine when to go into various charge modes, bulk, float, or equalize, and each unit connected to it will follow suit. So, you could just run multiple controllers into a single, large bank. 

Edited July 21, 2015 by Paul