WATER CURRENT TURBINE CASE STUDY
SUPPLY OF IRRIGATION WATER FOR 12 ACRE DATE FARM
One of a batch of four Garman turbines financed by a grant from the
System Details and Output
Output from the turbine flows through a 40m long 3" diameter polythene pipe up the bank to the start of the earth irrigation canal which is 14 metres above the river level during the summer. From the main canal the water· flows through a series of earth channels to small basins about 10m x 10. constructed so that when the first basin is filled with water automatically flows into the second and so on. This system allows the irrigation to go on without a full time attendant and means that the turbine can be run 24 hours per day. This farmer is the first irrigation user to make use of the full potential of the machine in this way. At the lowest river level the turbine delivers between 4.8 and 6.31/s to the start of the channel and. basin system and in its first three months of operation delivered 28,000 cubic metres of water (approximately 57cubic metres /ha/day). The entire farm is planted with dates underplanted with vegetables and animal fodder crops.
Advantages and Costs:
The turbine replaces an earlier diesel engine powered system which required continuous supplies of fuel and oil. Due to the isolation of the area, obtaining fuel supplies was a constant problem for the farmer. The turbine also operates without a full time attendant and only has to be cleaned and checked every few days. Operation is much more straight forward than a diesel pump and maintenance is only required once a year. The capital cost of the turbine is about four times the cost of the coventional technology, an Indian made diesel pump. When fuel and costs are taken into account the turbine becomes the cheaper option over a period of three years or more. Looked at from another angle, the capital cost of the turbine is equivalent to half of the farmer's annual profit from dates.
The farmer has already made arrangements with the Co-op Unions mobile workshops to carry out the annual maintenance when the turbine is moved in to the river bank during the first few days of the flood. In the event of a breakdown the mobile workshop can be summoned by sending a radio message from Abu Hamed. Spare parts are available for local currency from
The farm was visited by Thropton Energy Services staff eighteen months after the installalion. The turbine was working to the farmer's satisfaction and had at that time already run for more than 11,000 hours without breakdown and without any spare part being fitted.