Chinese researchers have been working on the subject, suggesting that a natural luffa sponge could generate enough electricity to power LEDs.
The luffa, sometimes referred to as loofah or sponge gourd, is a climbing plant most commonly found in Asia and Africa, whose fruits are used as sponges either in the bath or the kitchen.
But at a time when many scientists are working on solutions to produce energy sustainably, without harming the planet, the luffa could be given a new function.
New research led by researchers at Peking University in Beijing reveals the potential of these sponges to generate electricity to power small appliances.
Published in the journal Proceedings of the National Academy of Sciences (PNAS), this work is based on flexoelectricity, a physical phenomenon that occurs when certain materials – in this case luffa sponges or loofah – are subjected to pressure. Faced with this pressure, the flexoelectric material in question responds by producing an electric charge.
This is what Chinese researchers have been experimenting with, by modifying the structure of the natural sponge derived from luffa so that it produces enough energy to power light-emitting diodes.
“When a six-millimetre-thick section of this sponge was squashed by hand, it generated up to eight nanoamps of electricity.
“When this was placed into an electrical circuit with capacitors that could store the power of many squashes, it was able to briefly power six LED lights,” explains the New Scientist magazine in its coverage of this study.
The researchers see their findings as a valuable step in the path to greener energy.
“The developments we report constitute a paradigm for green and flexible sensors and energy harvesters with unique advantages of light weight, low cost, and full biodegradability,” the study in PNAS reads.
The question now is how much energy can be generated from these sponges, renowned for their natural fibre structure, biodegradability and skincare benefits.
If the study is to be believed, it would – for now – only be enough to power very small electrical appliances.
“To charge a mobile phone, we’d need a bigger chunk of luffa sponge, which may not be very practical at present. But if someone can make an artificial or man-made loofah by mimicking the microstructure and the chemical properties and the physical properties of loofah, then maybe we can increase [the amount of electricity produced]. It may inspire other designs,” explained Jianxiang Wang, one of the main authors of the research, in a statement to New Scientist.
The loofah may be of interest to scientists today as a means of generating green energy, but it’s far from the only solution currently being considered.
Chinese researchers recently presented a device for producing energy using raindrops, while a team from the Istituto Italiano di Tecnologia (IIT) has developed a rechargeable battery that is entirely edible.