Help with my system please

[Aradia]

Hey Aradia, it's been a couple months now. How did your project go? Any buyer's remorse on anything?

I'm shopping around and considering flexible 20w solar panels for maintaining the car battery and charging some devices. Wondered
what experience other solar enthusiasts are having with them.

-RayO

I connected everything a few days after my last post here and it has been working well ever since with no problems thank goodness.
Thank you for asking.

[RayO]

Hey Aradia, it's been a couple months now. How did your project go? Any buyer's remorse on anything?

I'm shopping around and considering flexible 20w solar panels for maintaining the car battery and charging some devices. Wondered
what experience other solar enthusiasts are having with them.

-RayO

[lkruper]

I noticed that the tone of a few of the out of left field hostile posts has also been softened some what. I appreciate that as it would put a bad taste in my mouth to have to read that repeatedly while reviewing information. I am sure other readers will appreciate it also. Thank you for that

I don't think I changed the tone... I think you are getting a thicker skin

[Aradia]

I noticed that the tone of a few of the out of left field hostile posts has also been softened some what. I appreciate that as it would put a bad taste in my mouth to have to read that repeatedly while reviewing information. I am sure other readers will appreciate it also. Thank you for that

[lkruper]

thank you

BTW I fixed all the units in my previous posts. Also, I saw that when I initially replied to you (when I was not rushed) I correctly calculated your system with 24v and then at the end switch to 12v. I have fixed that too, so that the calcs can be a resource and not too confusing to you and others who might read this later. I would encourage you to make a spreadsheet of all the possible loads and the duration in a 24 hr day you would run them. I have done that and keep on changing it. So I have a column with Y/N and change the formulas in Excel so that I can test many different configurations with different sizes of batteries, chargers, inverters and panels, etc.

I am still not satisfied and I keep changing things. For me, this is a long difficult but fun process.

[Aradia]

thank you

[lkruper]

Which panels do you suggest?

Brands are not my forte, but I have seen it discussed here that there are certain name brands that are from very large companies that will likely be here in 10 years when you need to replace an identical panel or 25 years to honor their warranty. Names like Kyocera, Panasonic, Sanyo. The economics of the larger panels are such that you can get a 250w panel for $250, or $1 / w. They are higher voltage and higher amperage and so you do need MPPT to take advantage of them.

The other thing to keep in mind is that these panels are larger and so shipping can be expensive. If you can find a local supplier and pick them up you will save money.

I would also encourage you to read the stickys on this site. They discuss many of the topics you need to master as you build this system.

[Aradia]

Which panels do you suggest?

[lkruper]

Thank you. I disagree that I will have to throw all of this in the trash to upgrade it. I can just get a new charge controller. I will certainly not throw my new panels or my batteries in the trash though . That was a bit harsh.

I don't recall using the word trash. Also, when I made that comment, it was not made for this short term project where you are balancing the items you just acquired. It was your description of a system that was fully powering a household by adding the water heater, washer/dryer and refrigeration to what you already had listed. If you add all that up you will find it hard to expand your starter system to accommodate it.

As for the panels, sure you can use them. But for bigger systems, the larger grid-tie panels are much more economical.

[Aradia]

Thanks for the suggestion. I am not afraid of a few simple equations at all. And with regard to my doom gloom comment, I was trying to lighten the air because a few unnecessarily harsh and unnecessarily antagonistic statements came from out left field and are in the record of this thread. They have nothing to do with math which is one of my fortes.

[bcroe]

Performance

Why are you a "solar fanatic" then? Thanks for your opinions anyways.
I send you bright sunny skies devoid of all doom and gloom.
Best wishes.

If you expect anything to actually perform, try to understand the math instead of denying
reality by name calling doom/gloom/opinion. One more thing to mention. DC heater
elements can meet their specs when matched up to a battery system. If you try to use
them directly connected to PV panels, the available power will practically never be fully
used. That is because the heater resistance will only match up to the available power at
one particular level of sunlight. Bruce Roe

[Aradia]

Thank you. I disagree that I will have to throw all of this in the trash to upgrade it. I can just get a new charge controller. I will certainly not throw my new panels or my batteries in the trash though . That was a bit harsh.

[lkruper]

I have another question. Someone referred to my system as 12v although I am using 12 v batteries in series to make 24 volt and with a 24 volt inverter. My panels each have open current of 46.6 volts. Doesn't that mean the system is 24 volt as opposed to 12 volt?

Yes, you are correct. I was mistaken to call it a 12v system.

[Aradia]

I have another question. Someone referred to my system as 12v although I am using 12 v batteries in series to make 24 volt and with a 24 volt inverter. My panels each have open current of 46.6 volts. Doesn't that mean the system is 24 volt as opposed to 12 volt? The vendor told me these panels can be used for either 12 or 24 volt systems.
PS It is refreshing to see a few equations. Reminds me of my calculus classes from long ago. I will have the hang of the math involved in this in no time I'm sure with the constant reinforcement here.

[J.P.M.]

You are not the first person who has brought that to my attention and I appreciate it. I will try harder to remember.... and perhaps fix the post now to boot.

Thank you.

And, to agree with your point about u-tube : If the concept of useful and somewhat accurate exchange of information has any meaning left, utube still pretty much sucks - for technical stuff anyway.