Organic batteries
From TheStudentWiki
Contents |
Introduction
Many new forms of batteries are being created which are designed to reduce the effects of global warming. These are known as 'organic batteries'. The different types of batteres listed below are the known organic batteries that have been created or are currently being developed.
Fuel Cells
What are fuel cells?
Fuel Cells are electrochemical energy conversion device. It uses external energy, it has two side’s one side called "anode" and the other side called "cathode". These two sides react creating energy. Fuel cells are different from batteries because normal batteries contain and store the chemicals within the cell, however a fuel cell dose not contain and store the chemicals inside. Fuel cells have separate containers.
Cost
The cost of using a fuel cell is $1000 per kilowatt; the goal is to reduce the overall cost, this is to compete with the modern market.
Products that run on fuel cells
Many ideas have been put in to place to use applications on fuel cells. One idea that Toshiba has come up with that use fuel cells is an MP3 player that runs on a 100mW cell. This cell is designed to run for up to 60 hours; it is long running and powerful. Toshiba have also been developing a version that can run laptops. It can acheive approximately 5 hours of run time, from the 12W fuel cell.
Beer batteries
Australian brewers Fosters have developed a method of using beer to generate energy. This is called the ‘Beer Battery’ which is a microbial fuel cell (MFC). Sugar consuming bacteria generates the power from the brewers’ waste water. The organic matter is consumed and the starch, alcohol and sugar are then broken down. Electricity, clean water and carbon dioxide are then produced.
Alcohol + Starch + Sugar -> Electricity + Clean Water + Carbon Dioxide.
A beer battery prototype was created at the University of Queensland in Australia. This battery held 10 litres (2.6425 gallons) of water. The final version of the battery holds 660 gallons of water. It was created at the Fosters brewery in September and produces 2 kilowatts of power.
The process was originally designed as a waste water treatment. Prof. Jurg Keller of The University of Queensland, Australia said “Brewery waste water is a particularly good source because it is very biodegradable and is highly concentrated, which does help in improving the performance of the cell.”
The clean water that is produced in the process is important in Australia as the country has a lack of clean water. The beer battery is a renewable energy source which means that it will not run out.
Microbial fuel cells
This type of battery uses Microbial Fuel Cells (MCF), microbiological life forms that are used in the generation of electricity. Examples include bacteria that are found in waste products and extracted from sewage, including the E. Coli strain. These are used as they are capable of breaking down carbohydrates and producing hydrogen. Electrons are obtained from the hydrogen through the use of oxidation in electrolysis, which then generates a small current of electrical energy.
Advantages and disadvantages
As there are little to no harmful by-products made during this process, this means energy can be generated without also produced substances that can damage the environment. As this method becomes more widespread, it reduces the need for these substances being made and eventually disposed of. For example, regular batteries usually contain zinc, manganese and alkaline materials – these are poisonous, cause irritation to the eyes and result in inflammation of the skin. With less of these being dumped, it would lower the amount of wildlife affected by these conditions.
However, the batteries that are made in this way are of a small size and do not produce much power. The output of one is just enough to power a pocket-sized calculator or a 40w light bulb. In addition, this type of battery is only used in small scale, limiting the energy that can be produced from this method.
Bacterial Batteries
What is a bacterial battery? A novel microbe, existed in marine sediments, is able to convert sugar into electricity with a %80 higher efficiency than any previously known organism Because sugar is abundant in the environment, a battery using the new microbes could supply economical electricity in remote places.
Scientists in the US report how the bacterium Rhodoferax ferrireducens can turn simple sugars - found in fruit - into electricity There's been a lot of interest in microbial fuel cells trying to covert sugar into electricity What is a R. ferrireducens? In the past, it’s been converted 10% or less of the available electrons, and now it is up over 80. R. ferrireducens was located in marine sediments in Virginia. "This is a unique organism, it is capable of generating electricity while feeding on simple sugars such as glucose (the main form of sugar in the environment), fructose (found in fruits), sucrose (in sugar cane and beet) and xylose (a constituent of wood and straw). It's like an electric plug, Advantages and Disadvantages You put it in the cell membrane and put the cells in a cathode to produce electricity. Although the new process is highly efficient, it is slow. There is not lot of power. It's barely enough to run a calculator." However, the prototype device worked for up to 25 days. In principle, it could allow a cup of sugar to power a 60-watt light bulb for 17 hours. Astronauts and people working in remote areas may one day power their communications systems with electricity derived from bacteria A bacterial battery could be used in environments where it is difficult or costly to charge batteries. The US Department of Defence is interested for powering underwater microphones and sonar. For people living in poor, remote communities, it could be possible to adapt the process so that they can use farm waste to power batteries.
While the prospects are good, the researchers say that more work needs to be done before their research can be exploited commercially.
External Links
http://science.howstuffworks.com/beer-battery.htm
New Scientist article on bacterial batteries
Group D
Stephen Kent
Will Seabrook
Tom Howarth
Mohsin Karim
Omer Celikdemir
