Published on August 5th, 2016 | by Tina Casey0
Renewable Energy Wars: Living Microbial Electricity Generators Vs. The Nukes
August 5th, 2016 by Tina Casey
Michigan State University is poised to enter the exciting field of microbial waste management with an electrifying renewable energy twist. Researchers at the school have demonstrated that they can grow layers of electricity producing bacteria on films, deploying a scalable process that’s this close to achieving commercial viability.
So, in a world where you can grow your own power plant consisting of gelatinous films of bacteria that can generate electricity from waste, is there still a place for nuclear energy?
Bacterial Electricity Vs. Nuclear Electricity
The short answer is probably, though perhaps not for long, at least in some countries.
Here in the US, for example, nuclear energy has hit a brick wall. Despite its attraction as a zero emission energy producer, nuclear power plants are rapidly proving themselves to be high cost, high risk dinosaurs in a future populated by low risk, low cost renewable resources like wind and solar.
In another demonstration of the pushback against nuclear energy, New York State’s recent, controversial decision to ramp up subsidies for its existing nuclear plants is already facing legal challenges.
The prospects for new nuclear power plants in the US are further dimmed by the capability of local communities to oppose them, and the reluctance of elected representatives to rile up their electorates.
In other countries, the status of nuclear growth is somewhat brighter. That appears to be particularly so in China, where nuclear fan Bill Gates has focused the efforts of his TerraPower nuclear company under the mantle of low carbon advocacy.
It’s also worth noting that while large scale, conventional power plants are falling by the wayside, the US Energy Department has been eyeballing a next-generation approach that includes small scale, modular technology.
Renewable Electricity From Bacteria
That finally brings us around to the electric bacteria.
No, giant throbbing gelatinous masses of renewable, electricity generating bacteria will not replace nuclear power plants on a one for one basis. However, the new MSU research illustrates how the scope of the renewable energy field is far outrunning both nuclear and fossil fuel technologies.
The new MSU research, from the lab of microbiologist Gemma Reguera, is based on the bacteria Geobacter sulfurreducensr. The tiny bug possesses nanoscale, hairlike filaments of protein called pili, that act as powerlines (if that rings a bell, you may be thinking of similar research at the University of Massachusetts, covered by CleanTechnica here and here).
The waste treatment angle comes in when Geobacter breathes (yes, bacterial cells have to breathe). In Geobacter, the respiratory process involves metals and minerals:
Geobacter bacteria use the protein nanowires to bind and breathe metal-containing minerals such as iron oxides and soluble toxic metals such as uranium. The toxins are mineralized on the nanowires’ surface, preventing the metals from permeating the cell.
Thanks to the magic of genetic engineering, the Reguera’s research team has been able to pump up the conductive properties of the pili to the point where it is possible to assemble a bacterial mass that is large enough to generate a useful charge.
Let’s Hear It For Renewable Energy
If you caught that thing about uranium, you’re on to something. Long after the last nuclear power plant has shuttered (in the US, at least), films of Geobacter could still be hard at work cleaning up the mess they leave behind, while generating electricity as a valuable byproduct.
Reguera spells out another important advantage of deploying living organisms to generate electricity:
We can use genetic engineering to tune the electronic and biochemical properties of the nanowires and enable new functionalities. We also can mimic the natural manufacturing process in the lab to mass-produce them in inexpensive and environmentally friendly processes. This contrasts dramatically with the manufacturing of manmade inorganic nanowires, which involve high temperatures, toxic solvents, vacuums and specialized equipment.
You can get the full lowdown in the journal Nature Communications under the rambunctious title, “Mechanistic stratification in electroactive biofilms of Geobacter sulfurreducens mediated by pilus nano wires.“
Clinton Vs. Trump On Renewable Energy
Since this is a presidential election cycle in the US, for the record, Democratic nominee Hillary Clinton has a full slate of proposals focusing on renewable energy and other means of transitioning to the low carbon economy of the future.
Nuclear energy does not get a mention, though Clinton has not called for closure of nuclear plants in the US. That could be a reflection of her affinity for realism in policymaking. Why go out of your way to call for a ban on something that’s already dying a slow death?
As for Republican contender Donald Trump, his campaign reached peak argle-bargle this week, so it’s a little difficult to tell where he’s coming down on the use of nuclear technology for generating electricity.
On the other hand, he seems quite enthusiastic about the prospect of deploying nuclear weapons, so stay tuned.