mppt vs pwm

jrnymn7 wrote:
Seems to me, if using 12v panels, if all you ever did was bulk charging, you wouldn't need a controller at all. And if you were to de-rate the 12v panels to max out at say 14.8v, you could abs charge without a controller, as well?

And yes, I do realize at times there would be insufficient voltage available for charging, but in a pinch, say if one's controller crapped out, couldn't you just use a direct connection?

at the very least you would need reverse blocking diodes

or at night the panels would become a load on the batteries using power
solar panels ARE solid state devices, they create voltage and current when exposed to light, but they also will use power if connect to batteries in the absence of light

there is also the issue of overcharge if the batteries are in storage and not being use
in any system above trickle charge a controller is needed