Green electricity production with living plants and bacteria in a fuel cell

TLDR

The world needs sustainable, efficient, and renewable energy production. The study introduces the plant microbial fuel cell (plant‑MFC), a concept that harnesses in situ bioenergy. In the plant‑MFC, plants secrete carbohydrate‑rich rhizodeposits that bacteria oxidize in a fuel cell to generate electricity. Using Reed mannagrass, the plant‑MFC produced a peak power of 67 mW m⁻², demonstrated nondestructive in‑situ harvesting, and projected 21 GJ ha⁻¹ yr⁻¹ (≈5800 kWh ha⁻¹ yr⁻¹) of carbon‑neutral electricity. © 2008 John Wiley & Sons, Ltd.

Abstract

The world needs sustainable, efficient, and renewable energy production. We present the plant microbial fuel cell (plant-MFC), a concept that exploits a bioenergy source in situ. In the plant-MFC, plants and bacteria were present to convert solar energy into green electricity. The principal idea is that plants produce rhizodeposits, mostly in the form of carbohydrates, and the bacteria convert these rhizodeposits into electrical energy via the fuel cell. Here, we demonstrated the proof of principle using Reed mannagrass. We achieved a maximal electrical power production of 67 mW m−2 anode surface. This system was characterized by: (1) nondestructive, in situ harvesting of bioenergy; (2) potential implementation in wetlands and poor soils without competition to food or conventional bioenergy production, which makes it an additional bioenergy supply; (3) an estimated potential electricity production of 21 GJ ha−1 year−1 (5800 kWh ha−1 year−1) in Europe; and (4) carbon neutral and combustion emission-free operation. Copyright © 2008 John Wiley & Sons, Ltd.