looking for input on dealing with shade

[solarexperimenter]

It is all very simple 5th grade math. What voltage and amp hour rating are these batteries?

Just a single AA NiMh is 1.2 volts @ 2500 mah takes a 10 watt panel to charge in a day.

You said it was physically impossible for my panel to charge even a watch battery. Turns out it isn't physically impossible at all.

2500mAh/0.17A = 14.7 hrs =/= inf. They'll charge. You said it was impossible for them to charge. It obviously isn't. 10W panel: 2500mAh/580mA = 4.3 hrs =/= 1 day. Even if you start adding in losses, it does not come up to a day.

Anyway, this has been fun. Time to figure out how to kill the notifications.

[russ]

You said it was physically impossible for my panel to charge even a watch battery. Turns out it isn't physically impossible at all.

2500mAh/0.17A = 14.7 hrs =/= inf. They'll charge. You said it was impossible for them to charge. It obviously isn't. 10W panel: 2500mAh/580mA = 4.3 hrs =/= 1 day. Even if you start adding in losses, it does not come up to a day.

Anyway, this has been fun. Time to figure out how to kill the notifications.

Goodbye and have fun- as you don't want to listen to someone who knows but to believe your own BS you must lead an "interesting" life.

[sdold]

Using his math, it looks like his panel would take around 4 days to charge a 2500 mAh 6v battery on days with 4 sun hours, if it didn't have to power his logger at the same time. Does that sound about right? I'm trying to see if I understand this.

[SunEagle]

Using his math, it looks like his panel would take around 4 days to charge a 2500 mAh 6v battery on days with 4 sun hours, if it didn't have to power his logger at the same time. Does that sound about right? I'm trying to see if I understand this.

Using math that 1 watt 6 volt panel with a 0.17amp output would take over 14.7 hours (about 4 x 4 hour days) to charge that 6 volt battery. But in reality since a 6v battery needs over 6volts to charge he would have had to put at least two of those panels in series to charge at all.

Now that 10 watt panel could have charged his 6 volt 2500ma battery in one day if he gets a lot of sunshine. Since he is now getting shade the charge time would extend into days.

[Mike90250]

Look for some shade panels on ebay, maybe they exist, Solar panels require direct sun.

[ZoNiE]

If you live in a large city, look on craigslist, find a panel around 100W or so, buy it. there are always new and used panels. Sometimes they come off of rental equipment, sometimes leftovers from solar installers. Pay a buck or less per watt.

Buy a cheap PWM 12V charge controller.

Get a car battery, or lawnmower or motorcycle 12V battery. Your application is not that much of an energy draw smaller may be better.

Build or buy (from china on ebay) a 12-5V DC-DC converter that has sufficient ampacity for your needs. If your project is small enough, a simple 7805 voltage regulator with a heat sink from Rodeo Shark may be all you need. Heck, even a voltage divider.

There you have a nice little solar power system that you can use for tons of little electronic projects.

Those $9 1W Panels are a waste of money. $9 per watt? Fughetabout it. Those are for calculators and the like.

The 18W panel is nearly as bad.

If you have a harbor freight, they have a little 10 foot LED light set with a battery and 3"x3" solar panel for $10. It may work. I bought one for kicks and put it on my patio, and it stays on all night. You could hack the parts out of it.