These experiments have been conducted during the open workshops of the What the Flok ? festival taking place in Marseille, from Septembre 29th to October 4th.

Design features

• Substrate: topsoil gathered from La Friche's garden - two days before assembly - inoculated with 10 mL of clay gathered in Niolon on the day of assembly.
  • Volume: 80*30*2 cm3
• Container: crate, covered with a transparent garbage plastic bag.
• Proton Exchange Membrane: printer paper with low amount of ink.
  • Surface: 80*30 cm2
• Water comes from La Friche's tap - maybe chlorinated.
• Anode: copper covered with carbon, extracted from a dead DELL PC battery found in the LFO storage space.
  • Surface: 70*5 cm2
• Cathode: copper covered with less carbon, extracted from the same battery.
  • Surface: 70*5 cm2

Performances

• Voltage: started at 30mV, went up avove 40, and dropped down to 0 in 2 hours.
• Current: started at 0.125 mA, and dropped down to 0 in 2 hours.

Max Power Measured: 3.75 microW

Design features

• Substrate: mud gathered from La Friche's garden on the day of assembly.
  • Volume: 80*30*2 cm3
• Container: crate, covered with a transparent garbage plastic bag.
• Proton Exchange Membrane: three to four overlapping sheets of newspaper, covered in ink.
  • Surface: 80*30 cm2
• Water: mainly rainwater from the mudsource, with some tap water (0.5L) to complement - maybe chlorinated.
• Anode: copper covered with carbon, extracted from a dead DELL PC battery found in the LFO storage space.
  • Surface: 70*5 cm2
• Cathode: copper covered with less carbon, extracted from the same battery.
  • Surface: 70*5 cm2

Performances

Performances on Day0:

• Voltage: around 5 mV.
• Current: around 0.1 mA.

Performances on Day1:

• Voltage: around 45 mV.
• Current: around 0.1 mA.

Performances on Day2:

• Voltage: around 130 mV peak.
• Current: around 0.5 mA peak.
• Strange measurement behavior:
  • Voltage starts at 80 mV, and builds up to 130 mV in about 15 minutes.
  • Current starts at 0.7mA and drops to 0.3mA in about 15 minutes too.

Performances on Day3:

• Voltage: around 250 mV, stable.
• Current: around 1.5 mA peak, decreasing slowly, stabilized around 0.60 mA.

Peak Power Measured: 375 microW.

Max (stable) Power Measured: 150 microW.

Design features

• Substrate: sea sediments gathered ten meters from the Catalan beach in Marseille on the day of assembly.
  • Volume: 0.5L
• Container: 2L plastic bottle.
• Proton Exchange Membrane: a piece of cardboard.
  • Surface: the bottle's section (diameter of 6-8 cm).
• Water: seewater.
• Anode: copper covered with carbon, extracted from a dead DELL PC battery found in the LFO storage space.
  • Surface: 50*5 cm2
• Cathode: copper covered with less carbon, scrap from the supercapacitors experiment.
  • Surface: 20*5 cm2

Performances

Performances on Day0:

• Voltage: about 13mV
• Current: about 0.1 mA

Max Power Measured: 1.3 mW

Observations

Even though the multimeter was connected the wrong way (+ on anode, - on cathode), we first had positive (and quite high) current and voltage value. Is this due to remanant charges from the PC battery ?