Renewable Energy and Nanotechnology

With the era of peak oil upon us – and growing concerns about the impact of climate change - there are ongoing debates in Ireland and elsewhere about future energy, with various alternative energies proposed from renewable to wind, to hydroelectric power and wave. Nuclear energy has also re-emerged as an option. But other, newer technologies are also being talked about, and indeed are well into research and development stages, in the areas of biotechnology and nanotechnology. For more background on energy planning and debates in Ireland, please see the ‘Ireland’s Energy Challenges’ document.

A proposed “bionano” solution at DCU

One of the bioengineered solutions offered by Dublin City University is a project funded by QUESTOR in Belfast  exploring bioelectricity production from wastewater in Microbial Fuel Cells , being investigated and developed by one of our biotechnology researchers at DCU, Dr. Enrico Marsili. There are two ‘green’ technological processes derived from this idea:  1) wastewater treatment and 2) the use of microbial cells as miniature ‘batteries’ to produce energy.  With increased populations, synergetic exercises like this are increasingly common – in this case how do we treat wastewater as well as creating a new type of energy production?

Clean water demands increase the consumption of fossil fuel-based energy reserves as well as global greenhouse gas emissions. Wastewater treatment plants (WWTPs) operation accounts for 1.5% of the electricity consumption and 5% of greenhouse gas emissions. Energy recovery technologies are proposed to reduce cost and energy consumption of WWTPs. MFCs convert the chemical energy of wastewater directly into electrical energy, through microbial catalysts. MFCs are very simple bioreactors, essentially vats that harnesses energy from biological processes. In one example, a “biofilm” is created from an organism called Shewanella oneidensis. It has been seen that these organisms are good at transferring electrons across metals. Bionanoscientists have been able to create special ”nanowires” as extended “arms” on these organisms, making them more electrochemically active.

However, there are some issues raised specifically about these microbial fuel cell (MFC) technologies, questions that could be described as both scientific and socio-political.

We need to gather as much knowledge on these issues as possible. Questions that we now open for wider discussion online are:

  • Specifically, how do bio/nano innovations compare, in MW output, to 1)wind  2) wave and 3) nuclear?  How can microbial fuel cells (MFCs) be made more efficient? What is expected of an MFC as a practical output for Irish homes?
  • Can an MFC solution be used in the short term to address municipal wastewater and energy needs in the greater Dublin area? What protocol can be implemented that allows community and local council influence on such a process?
  • How would a wind or wave strategy for Europe work , combined with  bio-nano solutions?
  • More generally, how ‘natural’ are bio- or nanotechnological innovations? How important is it for a ‘green Ireland’ to use ‘natural resources’ in partnership with our European neighbours?

‘Public Engagement in Sustainable Development, Dublin City University’

debate ended – 2 comments:

  1. Enrico Marsili wrote:

    Hello,
    I am one of the DCU researcher involved in energy recovery from wastewater.

    Energy recovery from WW cannot be compared in terms of output to “conventional” renewable
    energies such as solar and wind. MFCs can produce at best 100 W/m3 of reactor volume.
    MFCs cannot be compared to fission-derived energy, whose energy output is far superior to
    wind and solar technology. The main interest in MFCs raise from the fact they can generate electricity while degrading WW, thus achieving a double result and lowering the cost for conventional WW
    treatment. MFC efficiency is already quite high, about 80% or more or the energy contained in WW can be harvested. However, the cost per unit of power produced need to be reduced, for example by
    using more energetic substrate (primary wastewater or effluent of anaerobic digestion processes).

    MFC could be used at home in a fairly short time (5 yrs). The technology is already available, but
    typical home produce very diluted wastewater that may result in too little energy recovery.
    Surely, MFCs can be implemented in addition to standard sewage treatment in rural homes. The
    economic of the process requires further study. Further, the MFCs require expert operation
    and decision, above the average consumer experience.

    Datum: 23. March 2012 – 19:27 Uhr -