Not really designed as a serious light source, the lemon light by Yuri Suzuki is more of a value recognition enhancer to make people appreciate the value of power.

"Modern life is characterized by a separation of actual natural resources and the electrical power we use in daily life. The origin of electrical power has become invisible to us. People have forgotten about the natural forces that originally produce our light, heat and power. We are only faced with switches and electrical outlets in our homes and offices."

In order to use this light powered by a lemon battery, one actually needs to buy a real lemon, cut it in half and insert the light into it. It only just produces a weak light and thereby makes people aware of the value of power: If you need half a lemon for a weak light, then how many full lemons would you need for a strong one?