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 CANADA fund (Canadian Embassy, Addis Ababa) is providing round the clock irrigation for a twelve acre date farm beside the Nile. The farm is situated in a beautiful and very remote area twenty kilometres north west of Abu Hamed in northern Sudan. The turbine was manufactured by the Industrial Liaison Unit of the University of Atbara, Sudan under license from Thropton Energy Services, It was installed by the Nile State farmers Co-op Union mobile workshop technicians.
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.
Back Up:
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 Atbara,
Feed Back:
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.