Plugging into the power of sewage
19:00 10 March 2004
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Bruce Logan, Penn State University
Microbiology, University of Massachusetts
Sewage treatment, Wessex Water
The waste you flush down the toilet could one day power the lights in your home. So say researchers at Pennsylvania State University who last week revealed they have developed an electricity generator fuelled by sewage.

Even better, the device breaks down the harmful organic matter as it generates the electricity, so it does the job of a sewage-treatment plant at the same time. Penn State's microbial fuel cell (MFC) harnesses chemical techniques similar to those the body uses to break down food - but diverts the electrons liberated in the reactions to produce electrical energy.

"There are extraordinary benefits if this technology can be made to work," comments Bruce Rittmann, an environmental engineer at Northwestern University in Illinois.

Many developing countries urgently need sewage processing plants, for example, but they are prohibitively expensive, largely because they use so much power. Offsetting this cost by producing electricity at the same time could make all the difference, says Bruce Logan, who led the development team at Penn State.

Slurry of bacteria
Sewage contains a slurry of bacteria and undigested food, consisting of organic matter such as carbohydrates, proteins and lipids. The bacteria found in sewage treatment works use enzymes to oxidise organic matter, in a process that releases electrons.

Normally the electrons power respiratory reactions in the bacterial cells, and are eventually combined with oxygen molecules. However, by depriving the bacteria of oxygen on one side of the MFC, the electrons can be wrested from them and used to power a circuit.

The MFC comprises a sealed 15-centimetre-long can with a central cathode rod surrounded by a proton exchange membrane (PEM), which is permeable only to protons. Eight anodes are arranged around the cathode (see graphic).

Bacteria cluster around the anodes and break down the organic waste as it is pumped in, releasing electrons and protons. With no oxygen to help mop up the electrons, the bacteria's enzymes transfer them to the anodes, while the protons migrate through the water to the central cathode.

Polarised molecules on the PEM encourage the protons to pass through to the cathode. There they combine with oxygen from the air and electrons from the cathode to produce water. It this transfer of electrons at the electrodes that sets up the voltage between them, enabling the cell to power an external circuit.

Glucose solutions
The Penn State team's device is the first MFC that is specifically designed to produce electricity by processing human waste. Previous designs have only run on glucose solutions.

As yet his design is only producing a tenth of what he calculates its potential power output could be. Even so, if scaled up, this system would produce 51 kilowatts on the waste from 100,000 people, Logan says. He hopes to be able to boost its efficiency by increasing the surface area of the anodes or by finding more efficient anode material.

Microbiologist Derek Lovley of the University of Massachusetts at Amherst believes the most elegant aspect of Logan's MFC is its single-chamber design, which makes it very easy to scale up. Most glucose-powered MFCs comprise two anode and cathode chambers, separated by a PEM.

However, Lovley believes generating power from waste water on a large scale is a long way off: "One way to think of this technology is that it is currently at the state of development that solar power was 20 to 30 years ago - the principle has been shown, but there is a lot of work to do before this is widely used."



http://www.newscientist.com/article/dn4761-plugging-into-the-power-of-sewage.html

This would go a long way to alleviating Nigeria's energy deficit. The raw material is already present in abundance.

Brilliant idea

The claim that Solar Panels are Expensive in a place like Nigeria and hence not affordable is a myth. It is not based on fact but people's perception of the technology and mostly push by suppliers of generators to sell their products. Anyone in Nigeria can start on Solar today and in a matter of years reap the benefits of having solar as against generators and more. The average Nigerian family spends at least naira 100k a year on fueling generators and this does not include the price of the generator and other tools which run way into the hundreds of thousands on initial buy.

There is a house in Nigeria as we speak running off of solar energy. The total one time cost of Solar panels, equipment and installation to supply that 2 storey building with electricity 24 hours of the day is about $5000. Below is the cost of operation


Year One TOTAL  POWER COST
Solar Panels $ installation ~  $5000 ( Just in case you may need to add frames to hold the panels or you can do it yourself)
SunLight , Free

Year Two TOTAL  POWER COST

Solar panels maintanance fees,  $50 ( should anything happen that you even need maintainance for
SunLight , Free


Year Three TOTAL  POWER COST

Solar panels maintanance fees,  $50 ( should anything happen that you even need maintainance for
SunLight , Free

Year Four TOTAL  POWER COST

Solar panels maintanance fees,  $50 ( should anything happen that you even need maintainance for
SunLight , Free

Year Five TOTAL  POWER COST

Solar panels maintanance fees,  $50 ( should anything happen that you even need maintainance for
SunLight , Free


Year Six TOTAL  POWER COST

Solar panels maintanance fees,  $50 ( should anything happen that you even need maintainance for
SunLight , Free

Year Seven TOTAL  POWER COST

Solar panels maintanance fees,  $50 ( should anything happen that you even need maintainance for
SunLight , Free



,  you get the idea now . Now how much more expensive is this compared to what you currently have to deal with now In the first year alone, put together the amount you had to pay for the generator, the inverter and then how much you ended up paying to fuel the generator for the first year alone . Now put it together over time and tell me how much more expensive it is compared to solar??

I believe the main reason why Nigerians are not using solar much is cause instead of actually doing their research, people believe what they hear and are told of it and this puts more money into the sellers of generators and inverters for those as well as continues to put money into the pockets of the oil industry at the cost of the environment. Solar is not expensive if you consider it costs almost the same amount it would cost you to install and fuel a generator the first year alone. After the initial cost, it is practically free of charge since you do not have to fuel it and most of the panels come with at least 10 years warranty ( meaning you get at least 10 years out of use of it) and you get 24 hour electricty with no noice pollution and not environmental pollution of any kind.


Right now Nigerians spend about[b] $150 Million dollars on generators and fuel to gas them up EACH YEAR[/b]. We do not understand that this same can be spent one time for most of the country one and for all for power supply for at least 10 years. We need to start doing research instead of spewing the same old news which only amounts to repeating information that is passed down to us by people who themselves do not do their homework.

For stand-alone human waste energy system for electricity in Nigeria, I would not support.

Therefore, I strongly support the hybrid power system is the combinations of renewable energy sources such as PV (photovoltaic or solar panel), wind, micro-hydro, storage batteries/invertors, and waste (human waste, confiscated alcohol, & animal remains) powered generator sets to provide a reliable off-grid supply (a source of energy not connected to a grid).

How it works?

All energy comes from renewable energy sources like wind, solar, waves, hydro and biomass. The energy is either used directly as electricity or stored in hydrogen for use in transportation or to create electricity when the sun is not shinning or the wind is not blowing. The renewable energy is stored in hydrogen by splitting water into hydrogen and oxygen by use of electricity. This process is called electrolysis. Other productions methods will also be used to create hydrogen from fossil fuels. After the production hydrogen functions as an energy carrier that can be used to supply energy wherever it is needed. A fuel cell is used to convert the hydrogen into energy again. In the fuel cell hydrogen and oxygen (air) reacts and creates water as the only emission. The reaction creates electricity and heat that can be used in various applications. As fuel cells are very scaleable they can be used in all applications that needs energy, ranging from mobile cell phones, cars, buses and even as large heat and power plants. Fuel cell as a technology will be the next energy innovation step that will bring progress and prosperity to our societies, with as great an impact, as the steam engine and the combustion engine have had.

Relying only on renewable energy also solves the threats of oil depletion and pollution in the present energy system. This also makes it possible for everybody to produce their own energy creating more politically stability and benefits to all of us. But much has to be done before hydrogen is for real.
========
Therefore, do your research homework to resolve Nigeria Electricity solution in the name of hybrid renewable energy.

Nice thread please keep the info coming.

Nice thread indeed but it won't cause any change to Nigeria.
My brothers, it's good we are doing this but how powerful are we to implement this, even if the top goverment officials know this; they will just turn deaf eyes to it.

Stop waiting for government to do it all for you. Do your part in implementing the changes you can, pass on the information to inform others of what is available for them Now and let Government do what it will when it will. Obasanjo signed for Nuclear power in africa, it will not be realized for at least 10 to 15 years. If you want to wait that long to start living, that is your choice. If you decide to right now take advantage of what already exists for your own good now, terrific. The ball is in your court.

@Kobojunkie
I agree that solar energy is an option to consider, but your analysis are rather very optimistic

1. An average family does not spend $100k/year or do you mean 100k Naira?
2. You have to change your battery banks every 2-3 years, because of of our temperature and humidity. Batteries do not last forever! and these batteries are not cheap
3. When you increase number of solar panels, you need to increase your battery capacity.

What is the capacity of this $5k solar generator?
What type of backup batteries are you using? Ordinary or Deep cycle?

oldie:

@Kobojunkie
I agree that solar energy is an option to consider, but your analysis are rather very optimistic

1. An average family does not spend $100k/year or do you mean 100k Naira?
2. You have to change your battery banks every 2-3 years, because of of our temperature and humidity. Batteries do not last forever! and these batteries are not cheap
3. When you increase number of solar panels, you need to increase your battery capacity.

What is the capacity of this $5k solar generator?
What type of backup batteries are you using? Ordinary or Deep cycle?

1) I meant Naira sorry and not Dollars.

2) Changing the battery every 2 to 3 years is not for everyone and every situation. That depends on how and where you store them in the first place. If you store them in an area with less humid interations, you do not have to change them that often and that helps reduce your cost in the long run. Changing the batteries are not as expensive as you may think. Infact, the $5000 included cost of batteries for back up. For best information on battery banks, I suggest you read this article and if you have any questions, please contact the guy directly for additional information and follow up. http://www.nrel.gov/docs/fy02osti/31689.pdf

3) Like I said earlier, increasing solar panels does not mean you have to spend fortunes on battery cost. Batteries are not at all expensive to change or increase and you can get more batteries from any source you get your panels from and in some cases, car batteries can be used but are not suggested for best performance. If your radio dies, you get more batteries right?? So I see no reason why getting more batteries for solar panel increase will be an issue.

4) Capacity of the $5k generator installed is about 0.8KW (200W * 4) Panels . For battery see the link below as suggested earlier.

http://www.backwoodshome.com/articles2/yago87.html

http://www.backwoodshome.com/articles2/yago88.html

http://howto.altenergystore.com/How-To-Library/Batteries/Installing-Batteries-Considerations-for-an-Off-Grid-System/a66/

http://www.oksolar.com/battery/

http://www.oksolar.com/n_cart/search.asp?cat=Components&subcat=Batteries

http://www.survivalunlimited.com/batteries/batteryblunders.htm


http://store.altenergystore.com/Batteries/c434/

For a long-term solution, the hybrid system for non-grid power supply systems, is what I will recommend, just like uspry1, suggested

And for the solar system . . ., the capital outlay for a solar system, which is about $6,000-$7,000 per KW is still too expensive for the average Nigerian home
An average home will need about 2.5kva.
We also need to take into consideration, the efficiency of the solar power systems

In the interim, I use a semi-hybrid system of inverter, generator and NEPA

Support anything for electricity generation except nuclear.

Heck, more electricity is produced in Bradford UK than the whole of the entire country

Solar energy is more convenient, it is clean and secure. We have a lot of sunshine in Africa and we don't use it. Why?

People may not be aware of this but, human waste treatment facilities have many other benefits.

For example one of the bi-products of such facilities is Biochar and or humus(depending on the method). These material can be used as fertilizer and soil stability as well as water/nutrient retention, things African soil is in dire need of . http://en.wikipedia.org/wiki/Biochar.

Another bi-product would be Biogas/Bio-oil whose use is more than obvious. http://en.wikipedia.org/wiki/Biogas

These things could create synergy effects between industrial/commercial cities and the agricultural rural areas. Cities produce machinery/energy/fertilizer enhancing the capacity of the countryside. In return the countryside produces more food/cash crops to fuel the economic growth of cities.

Horus:

Solar energy is more convenient, it is clean and secure. We have a lot of sunshine in Africa and we don't use it. Why?

Too expensive, basically.

[size=15pt]forget nepa or phcn use this product
[/size]

Joburg has invested about R250-million on developing its landfill sites so that the stored methane gas can be tapped and used to generate renewable power for the City's grid.

THE methane gas caused by the degradation of bio-organic compounds at the city s landfill sites will now be drilled out and used to generate electricity for Joburg s power grid, thanks to a partnership between the City and a private consortium.

The project, which is expected to be fully operational by 2012, is called the Landfill Gas to Energy Clean Development Mechanism Project and is the first of its kind in Africa and another first for Joburg.

Launching the project on 22 September, Joburg s portfolio head of environment and infrastructure services, Roslynn Greeff, said it was aimed at mitigating harmful methane and other greenhouse gases being emitted from the landfills.

The City has made a capital investment of about R200-million on landfills and about 50-million on the Robinson Deep Landfill Site in Turfontein for the project to come to fruition.

It is the first of five projects to be developed across all landfill sites in the city. Work at the Marie Louise landfill is in progress and by June 2012 the Ennerdale, Linbro Park and Goudkoppies landfill sites would be complete.

Generating electricity

The utilisation of gas to generate electricity only commences once a landfill site has reached a reasonable depth and the potential for the ingress of oxygen has been reduced.

Greeff said Joburg s landfill sites were at the depth and are adversely affecting the environment and causing bad odours, which affect the quality of life of communities living near the landfill sites .

Engineers have designed and drilled boreholes deep into the Robinson Deep Landfill Site and pipes have been inserted into the boreholes to extract the methane gas. Each borehole is however capped off at the wellhead and is built 30 to 40 meters apart.

MMC Roslynn GreeffMMC Roslynn Greeff opens the landfill gas project The pipes are directed to a manifold, which feeds into a carrier main that filters the gas to an engine compound. The gas is then fed into the engine unit to achieve an ideal gas mixture and is used to generate renewable power. The green electricity is available for use on site and is fed into the City s grid which distributes it to the entire local network.

Greeff said the extraction and destruction of greenhouse gases had provided the City with an opportunity to receive revenue from the generation of emission reductions certificates, trade in carbon credits and generate renewable energy.

The project supports South Africa s commitments to the Kyoto Protocol, an international agreement linked to the United Nations Framework Convention on Climate Change (UNFCC), which aims to reduce greenhouse gas emissions and implement Clean Development Mechanism (CDM) projects.

http://www.elp.com/index/from-the-wires/wire_news_display/1506608536.html

^-- Good move by Joburg.

Solar Cells are the wrong way to go when considering solar energy development in a country like Nigeria. There is a technology that is simplicity itself, called thermoacoustics. It is a novel way of converting heat energy into sound energy, which can in turn be converted into electricity by a variety of low tech means; it has no moving parts and is basically a well designed pipe. Thermoacoustic Heat Engines have practical efficiencies of between 20% and 30% and highs of 48% have been achieved in research labs, this compares favourably with solar cells general efficiencies of about 5%.

It would be relatively easy to train our artisans to build such machines to tailored specs, whereas, it takes a high tech outlay to produce solar cells if we don't wish to import them. I was sure we had plans for how to build the machines at http://afrosciencecommunity.com/Article.aspx , but I've searched and not found any; we'll make it a point to publish some ASAP.

Thermoacoustics is miracle technology for any developing country blessed with abundant solar insolation as Nigeria is.

You can read a bit about Thermoacoustic Heat Engines here (also check out the references at the bottom of the page): http://www.en.wikipedia.org/wiki/Thermoacoustic_heat_engine

Record efficiency in conversion of heat to sound

Basic idea of thermo acoustics engineResearchers from the Energy research Centre of the Netherlands (ECN) have achieved a record efficiency in the conversion of heat to sound. In a so-called thermo-acoustic engine they have improved on the existing record of 41% to reach 48% of the maximum possible efficiency.

[img]http://www.ecn.nl/typo3temp/pics/2111566241.jpg[/img]

http://www.ecn.nl/news/newsletter-en/2009/february-2009/heat-to-sound/

Lagos I believe is about to do the same thing that Joburg is doing (Eko Ile can shed more light), Solar is too expensive and the batteries are not cheap either, most households need up to 3KVA, that costs money in panels and batteries that should be replaced in 2 years (our guys import batteries that do not last). We have natural gas, let the government just do what is conventional.

^-- cosign

I absolutely support the idea joor. Government must sha prepare to import workers because the day they interview for such workers, naija boys no go show face to handle raw materials but dem fit do the office and accountant job

using human waste to generate electricity is not a big deal,where you may likely have problem is during handling and if you can incorporate machines or robot to hand the human waste you have lesser work to do all you need to do is to control the robot.From your toilet straight into the bioreactor ,once the human waste decomposes it hardly smell.I have done some conversion of livestock and human waste into fuel for cooking,running generator as well.To use human waste the system must be a close system from the toilet to bioreactor and finally to the power plant which produces the electricity.FAO and WHO warn against the use of human waste because if not properly handled you stand the chance of contracting diseases.if properly handle it kills pathogen that may likely cause diseases.if anybody or cooperate organisation is interested in this we can team up to make it a reality.

The problem with power generated from human waste is that it's too little. But in a place with plenty of human waste, like in prisons, it could be a viable source of electricity.

I like Science, Great Guys keep it up