Join Date: Jul 2010
Thanked 15 Times in 14 Posts
Rep Power: 7
Re: MPPT vs. Shunting Solar Controller
Great video, I'll just throw in another analogy in case it helps.
The MPPT controller is like a transmission in a car. The transmission seeks out the most efficient ratio to convert the torque/RPM's (voltage/current) from the engine (panel) to the torque/RPM's it needs to drive the car (charge the battery). It can convert torque to RPM's and vice versa.
The transmission does the conversion efficiently AND lets the engine operate at the ideal point. Both are good.
The shunting controller on the other hand is like a clutch. It can only reduce the torque/RPM's it's given by allowing slippage and creating a heat in the process.
So the clutch is both inefficient at doing the conversion (because it creates heat) AND limits the freedom of the engine operating point. Both are bad.
Last edited by asdf38; 11-26-2012 at 12:22 PM.