Yea, super good idea. But how can 3.4w/sqr meter rival the fact that solar panels get about 240w/sqr meter? The sun gives us 800w/sqr meter. But still a good idea to get power from what´s there already.

@Toffe Kaal Maybe the cost per watt is equivalent.

So we can potentially plant wetlands that generate electricity? I can see the conversation 20 years from now: "Well, nice knowing you, New Orleans, but we gotta put the wetland back..."

What effect does the day night cycle have on electrical output?

Well I think the Day Night cycle would have little effect as the power is generated below ground by bacteria who have a surplus of food to last the night and longer as their growth can out last the plants life by wide margins. I think this is a great Idea and New Orleans will be done next hurricane like it or not Nature doesn't need permission.

I sure hope those guys in Wageningen got it right. and that it works for many plant species; imagine you stick one end of an electric cable in the bank of the Amazon river, than take the other end across the rain forest and light a bulb there by touching a root. you could get electrocuted too, how exciting.

"70 percent of organic material produced via photosynthesis that can’t be used by the plant and is excreted through the roots." Can that be true? I have a hard time believing even 10% of that.

Interesting - so lets do the numbers ... If they achieve their maximum of 3.2W/m2 (8x their current output) a 100m2 system would generate 2.8kW per year, or about equivalent to a 1.7kW system covering maybe 9m2 and costing $3500 (for panels & frames), both systems would need batteries/inverter/grid-tie etc. Sounds ambitious if they could achieve this at $35/m2 especially given the likely high cost of the electrodes.

so how big does the anode and cathode have to be? G90 galvanized sheet work? maybe a slightly acidic hydroponic roof? or would a base aquaponics solution work? great big 'ground' battery dry cell would be carbon /zinc?

Mercedes Biome is one step closer to being a reality just apply this tech to the car bulb to be grown