What volt system would this panel be a good choice for?
- Thread starter Whats-n-Watts
- Start date
BentleyJ
Solar Wizard
PV panels are not chosen based on battery voltage because the panel is not connected directly to the battery. Panels are connected to a charge controller which regulates charging output for a specific battery voltage and chemistry. The PV panels are then chosen to satisfy the input voltage and current requirement of the charge controller.
Whats-n-Watts
New Member
It's my understanding that it matters if your controller isn't a MPPT because it chokes output but otherwise not so much. Are these a good choice for 12v, 24v or even 36v systems?
Charge controllers typically support both12 and 24v batteries. This is determined automatically when you connect it to the battery Before connecting the panels.
Just make sure that whatever controller you choose supports your panel's voltage.
Also, how many panels are you getting, and are you going to connect them in series, parallel, or both?
Just make sure that whatever controller you choose supports your panel's voltage.
Also, how many panels are you getting, and are you going to connect them in series, parallel, or both?
Vmp is 34v for this panel. To get peak power the output voltage would be 34V. If you are using a PWM charge controller the voltage would match the battery voltage and your current can never be more than ISC (short circuit current) so you would only get 12V * 10 amps = 120 watts out of a 365 watt panel. If using a MPPT charge controller you could get a full 30 amps going into a 12v battery the full capacity of the panel.
A MPPT charge controller is more expensive than a PWM controller for a reason. A MPPT charge controller could support 12, 24,36, 48 so you could start low voltage and keep the same controller if you go up later.
In either case the charge controller is limited by the output current to the battery so it makes more sense to put 4 batteries in series than to put 4 batteries in parallel. A charge controller can handle 4x as much solar array at 48v as at 12v. Or put another way you'd need 4 charge controllers at 12v where one would be enough at 48V to handle the same wattage.
12V makes sense when you are limited to a single battery and you happen to have a engine driven alternator charging the battery.
In that case you can run the engine in the RV / service truck for example rather than running a generator to power a large load.... with the understanding that if you tried to run a microwave on a single car battery it would be dead in a matter of a few min. a much smaller 12v inverter could be used when there is nothing charging the battery.
These panels would work fine for any battery voltage with an MPPT charge controller (min 2 in series for 36 and 48v)
They would best matched for 24v if using a pwm controller, voltage is not high enough from a single panel for 36 or 48
12v and pwm would not be making the best use of the available capacity as described above.
A MPPT charge controller is more expensive than a PWM controller for a reason. A MPPT charge controller could support 12, 24,36, 48 so you could start low voltage and keep the same controller if you go up later.
In either case the charge controller is limited by the output current to the battery so it makes more sense to put 4 batteries in series than to put 4 batteries in parallel. A charge controller can handle 4x as much solar array at 48v as at 12v. Or put another way you'd need 4 charge controllers at 12v where one would be enough at 48V to handle the same wattage.
12V makes sense when you are limited to a single battery and you happen to have a engine driven alternator charging the battery.
In that case you can run the engine in the RV / service truck for example rather than running a generator to power a large load.... with the understanding that if you tried to run a microwave on a single car battery it would be dead in a matter of a few min. a much smaller 12v inverter could be used when there is nothing charging the battery.
These panels would work fine for any battery voltage with an MPPT charge controller (min 2 in series for 36 and 48v)
They would best matched for 24v if using a pwm controller, voltage is not high enough from a single panel for 36 or 48
12v and pwm would not be making the best use of the available capacity as described above.
Whats-n-Watts
New Member
Thank you and that makes perfect sense. I have two 12v80ah I am thinking of going with a 24v bank with and a couple of 365w panels to a grid tied 24v Mttp AIO controller/inverter. I was going to go 12v but I'm told 24v would be better. Good to know these will work either way. Thanks a bunch!
Whats-n-Watts
New Member
I plan to use two of these 365w 40.8v to power a shed with a mini fridge and two freezers on two 12v80ah lead acid deep cycle in series for 24v.
pollenface
Solar Addict
12v with mppt, 24v with mppt or pwm 
Whats-n-Watts
New Member
Thanks!!!!
