The key is power, not voltage. The power of such a large solar panel is very low and cannot match the power of a light bulb.
The solution is very simple. Just replace it with one. Light-emitting diode that consumes very little energy. It lights up, and it costs a lot less than a light bulb, only a few cents each.
Today, due to their high efficiency, low cost and long life, luminescent tubes have gradually replaced light bulbs in areas with low requirements. For example, ordinary flashlights, car taillights, brake lights, etc.
The 120V you mentioned between the computer case and ground is also induced static electricity. The voltage is high but the power is very low. It discharges as soon as it is turned on and cannot turn on the computer. bulb. If you have questions,ask them to me. I will ask you this forever. I do not understand either.
Solar cells rely on photovoltaic reactions to generate voltage. In fact, there is no current in any battery measured with a multimeter. Because it is not a closed loop. Only when a load is placed and a closed loop is formed will current flow. The current range impedance of the multimeter is very wide, and the principle of measuring current is not to measure the current passing through the multimeter itself, so you cannot measure the current with the multimeter.
In other words, your method of measuring current is wrong.