Bumping it up some.

Well, I decided to add some more to my solar experiment. Started out with (4) 100 watt 12volt panels, (2) Vmax 125ah batteries, a 1200 watt inverter, with a Renogy 30amp charge controller. Found (2) 180 watt 12volt panels at a good price, so bought those. Adding another Vmax 125ah battery and a 2nd Renogy 30 amp charge controller. My only goal at this point is to reliably run a desktop computer, 32" monitor, a DSL modem and charge my laptop in case of power outage during Florida storms. I just might have to learn to quit falling asleep while watching streamed TV. It takes a lot more juice than a person might think to run what seems to be just a few things. I'm slowly learning.
Need to beef up and add two 180 watt panels.

Nice!

Given your battery capacity, your peak charging should be 25-37.5A. With 760W of panels, you're at 760/12 = 63.3A.

Given:

1. Infrequently used system
2. batteries will just be floated most of the time
3. Batteries are often in absorption/float before peak charge current occurs.
4. Power use while charging decreases the charge current.

You're likely fine with the higher current provided you're mindful of the hazard of full current charging, though one more battery would be even better...

I deal with my narcolepsy by disabling autoplay and always setting a 60 minute sleep timer on the TV.

Your system can safely provide 125Ah * 12V = 1.5kWh/day (not using more than 50% of your total battery capacity).

Given the excess solar, you can generate about 3.8kWh/day, so you have a lot of potential to power hungry items during solar producing hours. While a typical residential fridge uses about 2kWh/day, you could probably accommodate that due to your excess solar. You could also cycle the fridge off for 6 hours per night to cut its overnight draw.

The desktop computer may be a big ask. They are horribly power hungry. My beast pulls 250W @ idle (custom build 8 core AMD, several HDD, thirsty ATI (before AMD) video board, with no consideration for power consumption), so it would be better to use it during solar producing hours and go standby/sleep/hibernate when not in use. A kill-a-watt would help sort that out.

Just ordered me a kill o watt meter. Stop my guessing and find some facts-haha

Am I correct in that adding battery in parallel will increase allowable charging current?

Hdonly said:

Am I correct in that adding battery in parallel will increase allowable charging current?

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No but it will give you more amp hours to run your electrical needs longer.

Hdonly said:

Am I correct in that adding battery in parallel will increase allowable charging current?

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Yes. The 3rd battery increases the necessary and allowable charge currents. You generally want to target about 15% of capacity, i.e., 0.15 * 125Ah = 18.75A/battery.

Hdonly said:

View attachment 29214

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Hey!
How come my telephone line just went dead??

snoobler said:

Yes. The 3rd battery increases the necessary and allowable charge currents. You generally want to target about 15% of capacity, i.e., 0.15 * 125Ah = 18.75A/battery.

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Thanks, that's what I thought. The third battery came in today and I think I will add a fourth. The extra panels are supposed to be here tomorrow.

Doh... I only counted 2 total batteries in my head. I thought you were adding a second. 3 is good and 4 is fine too.

125Ah * 4 *.15 = 75A. 10% would be 50A, so you're right in the middle.

For streaming I find that my Tivo bolt uses just a few amps at 12v. This is after replacing the hard drive with an SSD.

The main drive is SSD in my desktop. The secondary is mechanical. It is in idle unless watching recorded video or listening to music. As soon as my Kill-O-Watt comes in, I will know what's going on better. Should have got a Kill-O-Watt to start with. I'm slow, but I am "Old and Blonde"!

Mine's a cobbled together PC that I've been upgrading continuously since 1991. 4X 80mm fans; old, hungry, hot FX-8350, SSD, 5X 3.5" HDD, two in hot-swap bays. ATI HD6850 - HOT, loud and power hungry. It's on its 4th power supply in 8 years, and I've always splurged on high quality, expensive-ish supplies.

Something built within the last few years is probably way easier on the juice, especially if Intel/Nvidia based.

Kill-a-wat will tell all! Better late than never!

Built this one all new in 2014. Intel I5-4690K CPU@3.50GHz x 4. (1) 120GB SSD (1) 2TB Mech Drive Put in a 750watt power supply in anticipation of more hard drives down the road. 30 watt stereo chip amp driving old JBL L40 speakers. Never intended this setup for solar power. I'm sure I could build one drawing much less juice, but darn the audio sounds good. Just need MORE SUN!!!!

Here's a computer like the first one I bought, while in college. CompuPro/Godbout 8085/8088 S100 with dual 8" floppies. Booted faster than anything I've had since. Had a Qume and a Diablo daisy wheel printer. Wire-wrapped a few add-on boards for it.

Before that, I wire-wrapped a Z80.




Here's one I helped design in the 1980's:



Now I have a Dell Precision 7720 workstation laptop and an HP M775 color all-in-one.
Dual Xeon, nVidia P5000, dual 1GB flash, 64 GB ECC memory.
Cost the same number of dollars as the CompuPro

Software is so top-heavy these days.

Got up and made some coffee this morning (of course). Jumped in the truck and headed to Lowes to get some wood stuff. Got home and beefed up my solar panel mount to get ready for the new panels that I hope will be here Monday. More juice from Mr. Sol.

Hdonly said:

I just might have to learn to quit falling asleep while watching streamed TV. It takes a lot more juice than a person might think to run what seems to be just a few things.

Click to expand...

Solution to 1st problem-

sudo shutdown -h 02:00

Solution to 2nd problem-

I cheated and used a variable PSU set at 13.1v with some diodes to stop the very old psu from clicking at sun rise.
Now replaced with a battery charger - Tecsup premium 12v/25a set at 14.4/13.5- on all the time. v at battery is 13.3 min. No diodes.

I had to put in my solar hws to justify the standby usage of the PSUs.

I don't even understand 3/4 of what you said?

They're being a Linux nerd. super user commanded shutdown in 2 hours.

Not sure about the rest...

Got the two new panels (180 watt Newpower) up. Of course the wires are 3" too short to hook up to the parallel connectors I already had in my box of stuff. Now waiting on some "2 into 1" cables. Plus got the inside wiring done. I had used the left over PV wire I had on the right side of my board. Found some red 8gauge battery cable left over from another project to wire the left side. As soon as I get some more lugs in, I will go back and color code the right. Still have one more battery on the way.

Got the last battery in. Still waiting on the cables to parallel the the two newest panels together. Just using one of them for now.