This solar panel stabilizer circuit is designed using a FET transistor, an LM317 voltage regulator and some other common electronic components.
T1 connects or disconnects completely foreign load. Therefore, dissipation in the FET is (theoretically) zero, since the current through it or voltage across it is void. However, it is advisable to mount it on a small radiator (about 5 ° K / W).
When transistor T1 is blocked, entire solar panel energy is delivered to battery. When the battery voltage becomes too high, the FET is disabled.
If R is sized properly, it will dissipate all the energy provided by solar panel and therefore lowers panel voltage panel and the battery no longer charges. Schottky diode prevents battery discharge through the resistor shunting.
Voltages that connects / disconnects shunt resistor are adjustable with P1, respectively P2. Recommended Voltages are 14.1 V and 12 V
The circuit itself does not absorb a higher current than 4 mA.
BUZ10 can switch up to 20 A. The value of R is calculated from Ohm's law and
collector parameters. They must indicate the nominal values of the panel, for example on: 14.4 V at 8 A. In this case, 1.8 ohm resistor rated at 115 W.