Moss FM: How to Power a Radio with Photosynthesis

Plant-powered electricity is not a new idea, but its time is fast approaching. Photosynthesis, the process by which sunlight is transformed first into electrons and then into sugars, is the most efficient energy process on the planet. Now, a product designer and two Cambridge University scientists are putting that efficiency to use with Moss FM, the world's first radio powered by "biological solar panels."

The project is the brainchild of Swiss product designer Fabienne Felder, working in collaboration with Dr. Paolo Bombelli and Ross Dennis. Felder describes Moss FM as "biophilic design." Biophilia is a hypothesis that there is an instinctive bond between plant life and human beings. It sounds New Agey, but it literally means "love of living systems"—an idea that almost anyone can get behind.

"Moss FM is the world's first plant-powered radio, and the first working moss-powered object," writes Felder on her website. "It makes use of an emerging biophilic technology called Biophotovoltaics. Electrons and protons produced by photosynthesising plants are harnessed and transformed into electrical current."

In fashioning Moss FM, the team created ten Photo Microbial Fuel Cells (Photo-MFCs). They can either be connected in parallel or series, said Felder on the Moss FM Tumblr page, depending on the output and efficiency of each cell. Moss was chosen because it grows slowly, meaning they are "less efficient at converting the produced electrons and protons into sugars in the second stage—leaving us with bigger potential to collect and transform electrons into electrical current," according to Felder.

As for the growing of the moss, a stable environment was required. "Working with moss, we could of course power objects outdoors, but ultimately we are aiming for home objects," said Felder. "This means removing mosses from their natural habitat, which in turn makes their environment unstable."

To work around this, the team turned their attention to a number of Britain's 20,000 native moss species. Bombelli and Dennis, who regularly work with moss, ultimately experimented with several types of hydroponically-grown moss. Some worked well, others didn't. Once harnessed in microbial fuel cells, the team was then able to disrupt photosynthesis' electron-to-sugar conversion process, and draw electricity from the moss, thus powering the Moss FM's radio.

Felder, working on data from University of Cambridge and the UK Department of Energy & Climate Change, wrote that if "25 percent of Londoners (ca. 2.7 million people) charged their mobile phone on average for 2 hours every other day with moss," then the UK would "save enough electricity to power a small town [42.5 million kWh]." This would amount to annual savings of £6.81 million and 39,632 tons of CO2 a year." Bad news for energy corporations, but good news for people and the environment.

Felder cautions that biophotovoltaics are still at an experimental stage. Currently, the team only captures about 0.1 percent of the electrons produced by mosses. This is reflected in the design of Moss FM, which can only run for a few minutes via a moss-powered battery. But technological progress is a story of making gadgets more and more efficient. If not Felder, then someone else will find a way to enhance the efficiency of biophilic technology such as Moss FM.