This circuit has was inspired by a circuit by @Wesleytg
Using a D.C. Voltage source as the solar panel (simulating charger at 14.2v).
Using capacitor as battery (either 12v led acid or a 12 battery pack).
P FET is used to automate led turn on/off via 1 meg LDR and diode isolates solar charger while sun is not charging capacitor (Batteries).
Use switch to initiate change between panel day and night and LDR resistance is way less than 10k in full sunlight.
Depending on the systems battery and panel capacity, would decide the led configuration, low system capacity maybe 2v led at 20 mA. Higher system capacity maybe a Cree 1W - 5W higher power led.
