New plant-growth medium for increased power output of the Plant-Microbial Fuel Cell

► Electron-acceptors in plant-growth medium negatively influence current density P-MFC. ► P-buffer in plant-growth medium hampers plant-growth. ► NH4HCO3 is suitable nitrogen-source for plant-growth and high current density. ► SO4-presence in plant-growth medium improves current density. ► Composition plant-growth medium has large influence on current density P-MFC. In a Plant-Microbial Fuel Cell anode-conditions must be created that are favorable for plant growth and electricity production. One of the major aspects in this is the composition of the plant-growth medium. Hoagland medium has been used until now, with added phosphate buffer to reduce potential losses over the membrane because of differences in pH between anode and cathode. We developed a new, improved plant-growth medium that improves current production, while the plant keeps growing. This medium is a nitrate-less, ammonium-rich medium that contains all macro- and micro-nutrients necessary for plant growth, with a balanced amount of bicarbonate buffer. Sulphate presence in the plant-growth medium helps to keep a low anode-potential. With the new plant-growth medium the maximum current production of the Plant-Microbial Fuel Cell increased from 186mA/m2 to 469mA/m2.