Potato powered battery to the rescue of rural Kenyans

A potato powered battery trialed two years ago by scientists to cater for the lighting needs of the rural communities not connected to the national grid, is now ready for commercialization, a move that could benefit thousands of livelihoods in rural Kenya with tonnes of over produced potato and no electricity.

The research that was carried out by scientists from Hebrew University in Israel was targeting millions of rural households who practice potato farming and even produce more than they can consume and sell, and have not been connected to national electricity grid. Kenya has been such a country. In Kenya potato is the second most important food for families after maize. Approximately 500,000 Kenyan smallholder potato farmers produce about 1 million tonnes from 100,000 ha of cultivated land area.

However two thirds of this is not consumed or cannot find market due to over supply. This has led to various value addition ventures. The potato powered battery could therefore be another huge breakthrough especially to rural households who form the bulk of the producing lot in the country.  The Kenyan experience reverberates across the world especially in developing nations which informed the scientist's preference of potato. Potatoes were chosen because of their availability all over including the tropics and sub-tropics," he said. They are the world's fourth most abundant food crop," said Haim Rabinowitch one of the researchers in the project.

According to the scientists one slice of potato can generate 20 hours of light, and several slices could provide enough energy to power simple medical equipment and even a low-power computer. The potatoes however have to be boiled.


The team, which described its work in the Journal of Renewable and Sustainable Energy said its work hinges on a recent discovery that the electrical flow from potatoes, long known to be natural electrolytes, can be enhanced tenfold when their cell membranes are deliberately ruptured by boiling.
To demonstrate, the researchers created a series of batteries out of slices of boiled Desiree potatoes about the size of a standard mobile phone, though they say the type and size of potato slice do not determine its power.

The device had the same basic components as conventional batteries, consisting of two electrodes separated by an electrolyte (the potato). Each battery powered a small light for 20 hours, after which a new slice could be inserted.
Potato batteries are estimated to generate energy at a cost of approximately Sh800 per kilowatt hour, which compares favourably with the best performing 1.5 volt (AA) alkaline cells like Energizer batteries which generate energy at Sh4,000 per kilowatt.  The scientists now say potato-based batteries can be more than twice as efficient as a standard 1.5V battery — and 26 times cheaper.

Banana and strawberry batteries could also be used, said Rabinowitch, but their softer tissues would weaken the structure of the battery and the sugars could attract insects.
Kenyan scientists have welcomed the discovery saying it could be now provide more tangible value addition ventures to rural Kenyans who never see the full benefits of the potatoes they produce. “You can imagine if they get such a cheap and reliable source of energy. Most of them are used to kerosene and paraffin which is way expensive than electricity and yet they are the one's at the base of the economic pyramid. Value addition ventures like potato crisps and potato snacks only benefit the companies that make them after buying the potatoes at a dismal price for the farmers. The potato powered battery would be of direct benefit to these farmers,”said Douglas Katana a scientist.

                                                                    Written by Alice Muriranja for African Laughter

Tue, 21st May 2013
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