Monday Morning: Torrential Downpour
Amy Li
David Thompson Secondary
Floor Location : M 021 N

For some people, rainy days are a source of depression. However, what if raindrops could be harvested as a source of energy? The purpose of this project was to design and build a generator that would produce energy from raindrops. The hypothesis was that the bigger the raindrop, and higher it fell from, the more energy the raindrop would produce.

The central concept of the generator design was to use a coil of magnetic wire and a magnet to produce energy by means of electromagnet induction, where the kinetic energy of raindrops would cause the magnet to move and slice its magnetic field through the coils of wire. The generator was built and then tested by dropping raindrops 3 cm and 5 cm in diameter onto the generator at falling heights of 10 cm, 30 cm, and 1 m. The control was no raindrops, the independent variables were the sizes and heights at which the raindrops were released, and the dependent variable was the amount of energy produced. Based on the results from testing, parts were added to the generator to increase efficiency, and the generator was taken outside into actual rain for more testing.

The data from the testing confirmed that the larger the size of the raindrop, the more energy it produced. However, the other part of the hypothesis, which states that an increased height from which the raindrop falls will also increase the energy production, was rejected. At the height of 1 m, the raindrops splashed when they fell onto the generator, and as a result, kinetic energy was taken away and the generator produced less energy. This was particularity evident in the 3 mm raindrop dropped at a height of 1 m, since it actually produced less energy than its counterpart at 30 cm. These findings helped design the additions to the generator, which was a rain collector component 30 cm above the generator component, that concentrated the raindrops into larger drops of water. This design saw significant increases in energy production, with an overall average continuous production of 0.0185 volts, 0.00012 amps, and 2.2313 microwatts.

In conclusion, the purpose of producing energy from rain was achieved. The expectation that an increase in the size of the raindrop would increase the energy produced was correct, but the prediction that a greater drop height would also augment energy production was rejected, since splash resulting from fast falling speeds took away from the raindrops’ kinetic energy applied to the generator. However, a single generator will not produce sufficient energy to be significant enough to do anything other than indicate the presence of rain. With improved designs and compactness, a tower of these generators have the potential to power an LED or charge a battery. Perhaps on a Monday morning in the future, we can all smile at a torrential downpour.