info.uwe.ac.uk/news/UWENews/news.aspx?id=2598

Hi everyone,

@iaieropoulos, Great to see that your project was picked up by Bill & Melinda Gates Foundation for funding! Will the results/report be available in the future? I would be very interested to see the outcome.

Concerning the valuefromurine project; indeed electricity generation from urine is not the main/only focus in our project. We are developing a system which recovers nutrients (N, K, P) and possibly electricity from urine. P can be recovered as struvite (ie. KMP or MAP) and the ammonium recovery is based on an MFC. The ammonium recovery is based on the process of ammonium transport from anode to cathode with subsequent recovery of ammonia at the cathode, as described in our article Kuntke et al., 2012

From my point of view, electricity production in an MFC (also from urine) still has some flaws. We reached in our experiments 2.6 A/m2 at 0.68 W/m2 in stable operation over a week. But we also saw that the cathode became limiting for the whole process. The cells we used were identical to the one in the upfront mentioned article (surface area 100cm2). Which corresponds to a current of 26 mA and a power output of 6.8 mW (163 mWh/d*L_urine). This stands in clear contrast to a theoretical power output of 18-20 Wh/(d*L_urine), which could be produced under optimum conditions (high biodegradability (95%), high Coulombic Efficiency (85%), Voltage efficiency (70%)). So our focus is also to improve electricity generation by improvements to materials and performances.

Kind regards,
Philipp

Hi there,

Thank you for letting us know about this.

It is of course brilliant that this project has been launched, however it's not directly related to electricity generation from urine, which is what the Urine-tricity project is about. From the information available on that website, the project you are referring to, is an innovative approach to recovering nutrients from urine, but not electricity.

Kind regards,
Yannis

Hi all,

Just for your information:

A new EU project was recently launched on this with a pilot plant located at one of the Dutch water boards.

There is not much information yet on the website but I could imagine more will follow soon; you can follow here: www.valuefromurine.eu/.

(The fresh Dr.) Philipp Kuntke is managing the research; he can be reached under This email address is being protected from spambots. You need JavaScript enabled to view it.. I'll encourage him to also write a post here.

Mariska.

Dear Elizabeth,

Thank you for your message and the pertinent questions asked.

The amount of electricity produced from Microbial Fuel Cells (MFCs) is often a point of misconception, since different workers tend to quote different electrical output levels in the literature, using various normalisation methods. This is why in our work we have always been demonstrably proving the actual amount of electricity, by powering real world devices, such as: digital wristwatches, clocks, dc motors, dc pumps, LEDs, dc fans, whole robots such as EcoBots I,II and III (already published or publicised) and more... (not yet published). As Physicists, the only way to prove that something works is by getting it to do real work, and this is exactly what we have been showing over the years. The amazing thing about urine is that it increases the power output from our MFCs by at least 3x!
In terms of actual power output, our MFCs produce something between 100-300uW at approximately 0.4-0.6V, which is why we have been pursuing the miniaturisation & multiplication approach, when it comes to scale-up of size and electrical output.

The cost of these devices greatly depends on core materials & parts that are used in the assembly. Again, this is one area that we have considered seriously, especially in the context of communities with no access to high-tech facilities in the Developing World, which is of course one of the main criteria of the Bill & Melinda Gates Foundation. We have therefore calculated the cost of one of our 60mL MFC units, to be approximately £1.09, and this is what we would consider expensive, since it is the cost of the actual prototype. If mass-manufactured, then the actual cost/unit would be considerably less, which is what we are actively pursuing.

The answer to your question about the treatment of urine (i.e. after electricity extraction), is indeed in the presentation given at FSM2 in Durban, as well as in the RSC Physical Chemistry Chemical Physics, Journal (14:94-98) (pubs.rsc.org/en/Content/ArticleLanding/2012/CP/c1cp23213d).
But that's not the end! The MFC can produce cleaner (and I do choose my words carefully) water on the cathode side, as a result of its operation. Electrons and cations (including protons) coming from the bacterial half-cell, react with oxygen on the cathode half-cell, the by-product of which is water. Unless this reaction is completed, the MFC does not work, as shown in the plethora of oxygen-cathode-based MFCs in the literature. But one can collect water from the cathode, if one is careful about how this can be done. This is part of our work and the water collected (as shown in the FSM2 presentation) will need to be thoroughly analysed (not just using EDX as we have done so far), before we can make any further claims. The fact of the matter is that this water is cleaner than the wastewater or urine fed into the anode half-cell, and further uses (e.g. irrigation) of this cleaner water will become more obvious as we further analyse the samples.

Regarding the news story from the Lagos Maker Faire, I think it's remarkable that 14-15 year old girls from Nigeria have come together to produce that demonstrator, but there is a few elements to pay attention to. For example, the electrolytic cell by default requires electricity to operate, which as shown from the photos, comes from the generator. So one question one might ask would be, are the 6 hours of operation purely from the 1 litre of urine, or has the generator had some external energy input to begin with? Another thing to consider would be the elements and materials actually involved in the electrolytic cell, water filter and cylinder with liquid borax, what is their cost and what is their useful lifetime? In other words, how much would this system cost and how long would it last running? Although the setup might have been 'prep-ed' for the photo opportunity, there is of course the question of the loose tubes going into the compressed gas cylinder. And finally, 6 hours of electricity can mean a number things, and without proper quantification of this output, it is difficult to be conclusive.

Kind regards,
Yannis

Dear Yannis,

Thanks for introducing your grant on the forum. This is obviously very fundamental research - which needs to be done. I am impressed by the number of publications that have already come out of this research!

Without having read more than the abstracts of the papers: my main concern is that my gut feeling is that the amount of electricity that could possibly be produced from urine would be way too small to make such a system economically viable. I mean the technology is surely relatively expensive? Have you calculated the costs of such a fuel cell reactor?

We already have big problems making transport of urine, let alone treatment (such as struvite production) economically viable in any country of the world. Could a fuel cell from urine be cost efficient in the future or let's say under which conditions could it become financially viable?

In which way is the urine from your microbial fuel cell different than before, i.e. after you have "extracted" the electricity from it? Does it change colour, odour or any of its constituents? Would it still be just as useful as a fertiliser afterwards?

Oh, maybe I found the answer in your presentation here:

• MFCs lock N, P, & K into new cell material (harvested and used as fertiliser)
• Preliminary findings also show that ‘clean’ water can be produced and this is a function of the electrical power output
• Furthermore, the electricity generation from urine renders the effluent cleaner

And what is your take on this little discussion here on the forum about electricity from urine in this article about Nigerian students:
forum.susana.org/forum/categories/39-mis...rine-in-nigeria#2620
?
You are the urine electricity expert - does it make sense what was reported there or is it being exaggerated? Are you by any chance connected to those researchers in Nigeria? Could you perhaps write a short reply there on the forum?

Thanks for your time.

Regards,
Elisabeth

Dear all,
I would like to introduce to you a research grant by the Bill & Melinda Gates Foundation that I am leading here at the University of the West of England:

Title of grant: Urine-tricity: Electricity from urine
Subtitle: Generating electricity directly from urine, using Microbial Fuel Cells.
Name of lead organization: University of the West of England, Bristol; Bristol Robotics Laboratory

Primary contact at lead organization: Ioannis Ieropoulos
Grantee location: Bristol, United Kingdom
Developing country where the research is being or will be tested: Durban, S. Africa

Short description of the project:
The MFC is an energy transducer, with live (non-pathogenic) microorganisms as the bio-catalyst. It consists of two half-cells:- an anode (negative terminal) and a cathode (positive terminal) that are typically materialized in two different chambers. Microbes typically grow on the anode and continue with their normal metabolic processes. In the presence of an electrode and under the pressures of redox potential difference and consequent electrophilic attraction, they interact with the electrode and make it part of their natural anaerobic respiration, i.e. directly or indirectly transfer electrons onto the electrode. Microorganisms inside the anode of an MFC form a biofilm of fixed thickness, dictated by the ability and rate of electron transfer for respiration. These microorganisms form a stable semi-solid matrix onto the electrode surface, which becomes permanently stuck, robust and resistant, even at high flow rates. New daughter cells or other microbes, which have no access to the electrode, will remain in the anode until being flushed out. A very important feature of MFCs is the inherent link between electricity generation and waste (sludge or urine) break-down. This means that the higher the energy output levels, the better is the waste compound breakdown and the higher is the production of water at the cathode [2 incoming electrons and 2 protons per single water molecule]. Although different approaches can be employed for optimizing the MFC technology, the challenge of scaling up for practical applications remains unsolved. It has nonetheless been shown that higher energy density levels and optimum biofilm/electrode surface area–to–volume ratios, reside within smaller scale MFCs. This will be the scientific basis for the proposed work to succeed.

Goal(s):
The goal of this project is to recover useful levels of electrical energy directly from urine, and thus convert an existing – entirely unexploited – waste into a sustainable fuel for the future, with concomitant clean water production.

Objectives: (i) high power production from MFC stack; (ii) high (collective) clean water production from the MFC stack; (iii) kill-rates of introduced pathogens as a result of normal MFC stack operation and (iv) modification of existing prototype urinal/latrine to integrate with MFCs.

Start and end date: Start date, 1 May 2012; End date, 30 April 2013 (edit on 3 May 2017: this project received Phase 3 funding, new end date is 30 April 2018; the size of the Phase 3 funding by BMGF is $1,618,978)
Grant type: GCE R7
Research or implementation partners: no (not yet)

Links, further readings – results to date:
These are some of the most recent publications, and report on the work of my EPSRC Fellowship and of our PhD students.


1. Physical Chemistry Chemical Physics, The first self-sustainable microbial fuel cell stack. DOI: Phys. Chem. Chem. Phys. pubs.rsc.org/en/Content/ArticleLanding/2012/CP/C1CP23213D

This communication reports for the first time the direct utilisation of urine in MFCs for the production of electricity. Different conversion efficiencies were recorded, depending on the amount treated. Elements such as N, P, K can be locked into new biomass, thus removed from solution, resulting in recycling without environmental pollution.

2. International Journal of Hydrogen Energy, Miniature microbial fuel cells and stacks for urine utilization. DOI: dx.doi.org/10.1016/j.ijhydene.2012.09.062

3. ChemSusChem, Microbial fuel cells for robotics: energy autonomy through artificial symbiosis.
onlinelibrary.wiley.com/doi/10.1002/cssc.201200283/abstract

The development of the microbial fuel cell (MFC) technology has seen an enormous growth over the last hundred years since its inception by Potter in 1911. The technology has reached a level of maturity that it is now considered to be a field in its own right with a growing scientific community. The highest level of activity has been recorded over the last decade and it is perhaps considered commonplace that MFCs are primarily suitable for stationary, passive wastewater treatment applications. Sceptics have certainly not considered MFCs as serious contenders in the race for developing renewable energy technologies. Yet this is the only type of alternative system that can convert organic waste—widely distributed around the globe—directly into electricity, and therefore, the only technology that will allow artificial agents to autonomously operate in a plethora of environments. This Minireview describes the history and current state-of-the-art regarding MFCs in robotics and their vital role in artificial symbiosis and autonomy. Furthermore, the article demonstrates how pursuing practical robotic applications can provide insights of the core MFC technology in general.

4. Bioresource Technology, MFC-cascade stacks maximise COD reduction and avoid voltage reversal under adverse conditions. DOI: dx.doi.org/10.1016/j.biortech.2013.01.119

5. Journal of Power Sources, Current Generation in Membraneless Single Chamber Microbial Fuel Cells (MFCs) Treating Urine, DOI: dx.doi.org/10.1016/j.jpowsour.2013.03.095

6. Bioresource Technology, Maximising electricity production by controlling the biofilm specific growth rate in microbial fuel cells. DOI: dx.doi.org/10.1016/j.biortech.2012.05.054

7. Bioelectrochemistry, The overshoot phenomenon as a function of internal resistance in microbial fuel cells. DOI: dx.doi.org/10.1016/j.bioelechem.2011.01.001

Presentation at the FSM-2 Conference:
www.susana.org/images/documents/07-cap-d...gland-bristol-uk.pdf

Paper at FSM2 Conference: www.susana.org/_resources/documents/defa...-1624-ieropolous.pdf

Video of my presentation at the FSM2 Conference:


The journal papers that I listed above are not open access journals. But you can see the abstract by clicking on the links above. I can e-mail you a copy of the papers if needed (This email address is being protected from spambots. You need JavaScript enabled to view it.).

Questions? Comments? Ideas?

Our priority at the moment is the deadline for the Phase-II for our project, which is fast approaching.

Regards,
Yannis

Dr. Ioannis A. Ieropoulos
Associate Professor
BioEnergy & Self Sustainable Systems Theme Leader
EPSRC Career Acceleration Fellow

Bristol Robotics Laboratory
T-Building
Frenchay Campus, (North Entrance)
Bristol, BS16 1QY
UK
Web: www.brl.ac.uk/researchthemes/bioenergyselfsustainable.aspx

Going through the Round 7 awarded projects, one can easily notice that there are a lot of great ideas for the utilisation of waste. It’s great that so many colleagues are thinking about this concept, since it is probably one of the very few ways that useful energy can be harmlessly generated and sanitation can be potentially improved. The Bill & Melinda Gates Foundation is a wonderful way of taking such ideas forward and I’d just like to say to everyone, very best wishes with their projects.