Simple but efficient LED light for Garden. Turns on in the evening and turns off in the morning. 6 Volt Solar panel charges the battery in sunlight. 4 volt battery power the LED in night. During day time, PNP Transistor BD140 remains off due to the positive state of its base through 4.7 K resistor. When the current from the solar panel decreases in the evening, base of BD140 will be pulled to ground via 1 M resistor and the transistor turns on to light the 1 watt White LED. In the morning, the condition reverses and the LED turns off.