Here’s a clock for those who have no clock and a spare lemon tree in the backyard. The tree will come in handy since this clock is powered by the energy of a lemon, which will power it for a week or longer. The design is intended to remind us that nature is still our direct energy source.
When life hands you lemons and a lemon powered clock, most people would just make lemonade and get the time from the microwave. But some of us will put lemons on our clock, and through the sour sucking power of citrus, attract fruit flies until we give up this novelty clock design.
It works using grade school chemistry for power. An electrolysis of zinc and copper (the plug under the lemon) in a salted or acid liquid (the lemon). Oxidation creates the electricity.