15A MPPT/ 12v Batts/24v Solar Panels

Blf13,

I see from the linked photo gallery, I need more add on panels for my 'Little solar electric scooter, might mo' to make it from Texas to LA.LLL Pictures coming soon.:)

O&S
Floyd

Scroll down to the photo gallery and the http://www.windturbine.ca/sun_panels.htmlscooter

JiminDenver wrote:
We did warn you that solar was addicting didn't we?

The answer is 'no' and now I'm on the hook. Got the Electric/Solar scooter ready so now it's on to the "Texas cabin" off grid.

What's next?

O&S

We did warn you that solar was addicting didn't we?

smkettner wrote:

Old & Slow wrote:
I need some 12" wide 24v panels too. Any ideas?

Even 12v panels of any reasonable size are more than 12" wide. You could connect two same 12v panels in series.

Maybe unisolar would work but they are 16" wide.
http://www.amazon.com/UniSolar-PVL-144-Laminate-Amorphous-Solar/dp/B003ZZLW68/ref=pd_sbs_misc_8

It's difficult to find special purpose panels. I had the bright solar idea of perhaps adding some panels to the 'Little might mo' electric scooter. I could hinge them around the perimeter and raise them when at rest. Texas to LA:C

Again, thanks to one of our Solar stars.

O&S
Floyd

Old & Slow wrote:
I need some 12" wide 24v panels too. Any ideas?

Even 12v panels of any reasonable size are more than 12" wide. You could connect two same 12v panels in series.

Maybe unisolar would work but they are 16" wide.
http://www.amazon.com/UniSolar-PVL-144-Laminate-Amorphous-Solar/dp/B003ZZLW68/ref=pd_sbs_misc_8

A MPPT converter will just scale voltage down and amperage up to feed the panels.

A PWM controller will lop off the higher voltage, so if you have a 200 watt, 24V panel, essentially you will get half of that into your batteries.

Old & Slow, I thought you bought an MPPT controller?
If you hook it to your battery first, then the panels, it will figure out you now have a 12V battery connected and charge it accordingly.

smkettner wrote:
The 24v panel to 12v battery works great with the correct MPPT controller.
I have three 24v panels in series producing over 90 volts to charge my 12v battery.

I recommend Morningstar
http://www.solarblvd.com/Charge-Controllers-MPPT-Charge-Controllers-Morningstar/c6_46_228/p2000/MorningStar-SunSaver-SS-MPPT-15L-Charge-Controller/product_info.html

If I knew then (when a ordered the $60 MPPT on hand)what I know now, the one on the link would be in hand. The extra 24v/120w panel I have from SolarBlvd will be used in the Texas cabin with the MPPT in a 12v system. It was to large and heavy for the 'little mighty mo' e/scooter, so I now need to use some extra stuff. I'm Using a 20a 12/24v PWM controller with the 24v e/scooter. Anyway, I now feel safe using the 15a 12v/24v Mppt and the 24v/120w panel together with the 12v battery bank on my 'things to buy list'.

Side note. I like the folks at SolarBlvd. Will order from them again.

I need some 12" wide 24v panels too. Any ideas?

One big Texas thanks to all the great RV.Net Tech Issues folks.

O&S
Floyd

You do need a MPPT controller to use a 24v panel with a 12v battery. There are work arounds but you lose a lot of the power available.

Don't you have a 200+ watt panel. 15a may not be enough. My 230w panel gets above 16a and a 15a controller would just clip the extra. There is also the concept that you need a 20% buffer meaning at least a 20a mppt controller.

The Eco-worthy 20a MPPT controller I use isn't the cheapest at $100 but I can vouch that it is functional, adjustable and keeps our batteries very happy even with the panel flat with only morning sun.

The work arounds I know of are a PWM controller that could handle high voltage panels. About the same price but you lose the high voltage advantage. I've heard you could connect the panel directly and disconnect it when the battery gets to a certain voltage. Might be possible but I'm not doing it. LOL