voltage from solar panel question

[gb michigan]

i am looking to buy a solar panel to charge a 80 amp hour 12volt battery,and I have found a panel that is listed as a 100watt 18v 12 v panel.I have a sunsaver 10 amp controller.Is this going to do the job for me or is the voltage to high?
thanks.

[SunEagle]

Hello gb michigan and welcome to Solar Panel Talk

Depends on what the Imp rating of that 100 watt panel is. My guess is that it will be around 5.5 amps which is a little low to recharge that 80Ah battery. You really need somewhere between 7 & 10 amps or C/12 and C/8 where C = Ah rating of the battery.

Now the 18v is just right to charge a 12volt battery but you will need a little more panel wattage for that battery. Especially if you discharge it more than 25% and get less than a couple of hours of useful sunlight or in solar terms "insolation" which is usually the hours just before and after Noon. More in the Summer. Less in the Winter.

[gb michigan]

thanks Suneagle,

looks like i will be ok.We have a very small teardrop trailer and have occasional times where we use battery to power led lights and a tv when grid electric is nor available.

[SunEagle]

thanks Suneagle,

looks like i will be ok.We have a very small teardrop trailer and have occasional times where we use battery to power led lights and a tv when grid electric is nor available.

You might want to look at a 150 watt panel and 15 amp CC or go with a 65Ah battery. That would balance out your system better. Good luck and have fun.

[gb michigan]

thanks for the help

[TaraByers]

Hi..i am a new user here. As per my knowledge it will be around 5.5 amps which is a little low to recharge that 80Ah battery. You really need somewhere between 7 & 10 amps or C/12 and C/8 where C = Ah rating of the battery. The 18v is just right to charge a 12volt battery but you will need a little more panel wattage for that battery. Especially if you discharge it more than 25% and get less than a couple of hours of useful sunlight or in solar terms "insolation" which is usually the hours just before and after Noon.

http://www.7pcb.com

[SunEagle]

Hi..i am a new user here. As per my knowledge it will be around 5.5 amps which is a little low to recharge that 80Ah battery. You really need somewhere between 7 & 10 amps or C/12 and C/8 where C = Ah rating of the battery. The 18v is just right to charge a 12volt battery but you will need a little more panel wattage for that battery. Especially if you discharge it more than 25% and get less than a couple of hours of useful sunlight or in solar terms "insolation" which is usually the hours just before and after Noon.

At least mention where you got that information you posted because I hate someone that plagiarizes and does not give credit to the originator. Which by the way was ME.

TaraByers. You have been put on notice and will be watched by me and the other MODS.

[PNjunction]

Be sure to set the jumper right on the Sunsaver! If you are running with a flooded or AGM battery, remove the jumper.

If you don't, the absorb voltage will be around 14.1v, which is ok for a GEL (which you shouldn't run with solar usually). That will result in a chronic undercharge of a flooded or sealed agm.

Too often, those running agm's will just accept a charge controller's "sealed" setting on the case silkscreen printing, and in many cases, this is only appropriate for a true GEL chemistry. So check the manual for the voltages, and you'll find that the absorb voltage you want with flooded or agm is UNjumpered at 14.4v with the Morningstar.