A new biofuel production platform which can improve energy recovery 20 times compared with conventional methods has been discovered by researchers at Michigan State University.

The microbial electrolysis cell or M.E.C. is a bioelectrochemical system that uses microbes to generate biofuel and hydrogen from agro-wastes.

It employs second bacterium Geobacter sulfurreducens to break down and ferment agricultural wastes into ethanol. When the bacterium is added to the wastes, it will generate electricity while removing byproducts or non-ethanol materials.

Electricity produced from the second bacterium is not collected as an output, but it is used to generate hydrogen from the M.E.C. that doubles the capacity to recover energy, said Michigan State University microbiologist Gemma Reguera.

Similar microbes have been tested earlier in corn stover, a common component for biofuels and energy recovery resulted to about 3.5 percent. However, with M.E.C used in corn stover, the energy recovery reached 35 to 40 percent.

"This is because the bacterium was carefully selected to degrade and ferment agricultural wastes into ethanol efficiently and to produce byproducts that could be metabolized by the electricity-producing bacterium," Ms. Reguera said.

The energy recovery is increased to 73 percent compared to the existing process, which makes the platform attractive and efficient for processing agricultural wastes.

The M.E.C. treats corn stover using the ammonia fiber expansion process, a pre-treatment technology that is also developed at Michigan State.

Currently, the university is working to improve the platform with plans to scale it up on a commercial basis.

It looks forward to create decentralized systems that can help process agro-wastes. The decentralized systems could be modified at small to medium scales to provide an economical method to reuse wastes as well as generate fuel for farms. – C. Dominguez