The potato-powered alarm clock has become somewhat of a science fair cliché. But one Dutch company is hoping to take a similar principle and apply it on a much larger scale.
Plant-e, a technology company spun off from the sub-department of Environmental Technology of Wageningen University, is aiming to scale up electricity generation from living plants for a wide variety of potential uses. Plant-e's systems work by inserting electrodes into soil, where they "harvest" electrons from bacteria breaking down sugars that are being released by plant roots.
So far, the amount of electricity being harvested is relatively modest. Two working installations exist, one in a public park in Hembrug, Netherlands, and one near the company's headquarters in Wageningen, both lighting up a small array of LED light bulbs. According to Plant-e's website, future applications may include green roofs that power mobile chargers or a WiFi hotspot powered by about 100 square feet of parkland.
As detailed in a profile in Yes Magazine, despite the ambitious goals of the company founders, it looks like the technology has a long way to go before it can ever hope to compete with established sources of power:
Ramaraja Ramasamy, an adjunct professor at the University of Georgia College of Engineering, said that what Plant-e uses is called a “sediment microbial fuel cell.” He cautions readers that this technology is not advanced enough to compete with solar panels and wind turbines, which have been in development for years.
“It’s not making enough energy to have any reliable commercial product. That doesn’t mean that it will not be. We are too early in the research,” Ramasamy explained. “If I come to you and say, ‘Do you want to power that 100-watt bulb?’ You probably need an acre of land and dirt to get the electricity from. Is that feasible? No.”
That said, Yes Magazine details how Plant-e is now working on a tubular system which can be inserted into the soils of existing wetlands and other ecosystems, and this offers considerable advantages that could help move things forward. Not only does it eliminate the cost, resources and labor involved in dedicated planting modules, but it would also alleviate land use pressures and broaden the range of potential applications.
Given the relatively low power output, one place where microbial fuel cells may just work is for small-scale electricity generation in the developing world. As the rapid spread of solar lanterns as a replacement for kerosene in Africa has shown, small amounts of power can make a big difference by charging cell phones or allowing children to study at night. So if Plant-e can crack the process of efficiently producing small amounts of usable power by simply plugging into the soils of rice paddies or wetlands, they may well find a market in remote, rural communities.
So mark this one as an idea to be watched, but don't go writing off solar panels just yet. Here's a bit more of a pitch from the company itself.
Related on MNN: