Lesotho moves to study viability of pumped-storage hydropower scheme

The Lesotho Electricity Company (LEC) has issued a request for expressions of interest from consulting firms able to conduct a prefeasibility study into the development of a pumped-storage scheme in the mountainous Southern African country, which is surrounded on all sides by its power stressed neighbour, South Africa.
It is understood that the scheme, known as Monontša, could potentially yield 1 000 MW of peaking capacity for consumption in both Lesotho and South Africa.
Several Lesotho sites, some of which are associated with the giant Lesotho Highlands Water Project, where reportedly assessed earlier in the decade by South African utility Eskom for their hydropower potential, with Monontša having been identified a possible site.
That initial reconnaissance study, sought sites with an elevation of between 400 m and 1 000 m, which could also accommodate dams capable of storing about 20-million m3 of water, both at the top and at the bottom of the mountain.
The Lesotho government has now secured a loan and a grant from the African Development Bank’s (AfDB’s) African Development Fund to study power supply projects, under the ‘Lesotho Electricity Supply Project’, part of which would be used to cover the cost of the pumped-storage prefeasibility study, with the LEC acting as the implementing agency.
The winning bidder would be required to: conduct a topographical survey of the entire site; assess geological and geotechnical conditions; propose dam types and locations; make an assessment of reservoir capacities; complete hydrology and siltation studies; assess environmental and social impacts; propose a preliminary design of all main components of the scheme; and provide an opinion on the technical and economic feasibility of the scheme.
The deadline for bids is 12:00 on July 9, 2010, and a short list of six firms would be compiled in accordance with the procedures set out in the AfDB’s rules and procedures for the use of consultants.
Meanwhile, the LEC is seeking bids for the construction of new distribution infrastructure, including the development of 33 kV lines and 11 kV lines, as well as substations.
Through the project, which also forms part of the Lesotho Electricity Supply Project, the LEC plans to add more than 4 000 service connections.
The project is also backed by the AfDB and contractors have until 12:00 on July 19, 2010, to deliver their bids.
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