Nalubaale Hydroelectric Power Station

Nalubaale Power Station, formerly known as Owen Falls Dam, is a hydroelectric power station across the White Nile near its source at Lake Victoria in Uganda. Nalubaale is the Luganda name for Lake Victoria.

Nalubaale Hydroelectric Power Station
View from top of dam
Nalubaale Hydroelectric Power Station is located in Uganda
Nalubaale Hydroelectric Power Station
Location of Nalubaale Hydroelectric Power Station in Uganda
Nalubaale Hydroelectric Power Station is located in Africa
Nalubaale Hydroelectric Power Station
Nalubaale Hydroelectric Power Station (Africa)
Nalubaale Hydroelectric Power Station is located in Earth
Nalubaale Hydroelectric Power Station
Nalubaale Hydroelectric Power Station (Earth)
CountryUganda
LocationJinja
Coordinates00°26′37″N 33°11′06″E / 0.44361°N 33.18500°E / 0.44361; 33.18500
PurposePower
StatusOperational
Opening date1954; 70 years ago (1954)
Operator(s)Uganda Electricity Generation Company Limited
Dam and spillways
ImpoundsWhite Nile
Spillways6
Spillway typeUnder sluice
Nalubaale Power Station
Operator(s)Uganda Electricity Generation Company Limited
Turbines10
Installed capacity180 MW (240,000 hp)[1]
Website
[uegcl.go.ug]
Satellite image showing the location of the dam in relation to Lake Victoria
Construction of the Owen Falls Dam in early 1950s

Location

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The dam sits across the Nile River between the town of Jinja, in Jinja District approximately 85 kilometres (53 mi), by road, east of Kampala, Uganda's capital and largest city.[2]

History

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Before the construction of the dam, water levels on Lake Victoria were moderated by a natural rock dam on the north side of the lake. Rising lake waters would spill over the natural dam into the White Nile, which flows through Uganda, South Sudan, Sudan, and Egypt before emptying into the Mediterranean Sea. When water levels dropped too low, flow into the river ceased.

In 1947, Charles Redvers Westlake, an English engineer, reported to the Colonial Government of Uganda recommending the construction of a hydroelectric dam at Owen Falls near the city of Jinja. This led to the establishment of the Uganda Electricity Board (UEB), with Westlake as its first chairman. A treaty between Uganda and Egypt ensured that the dam would not alter the natural flow of the Nile. The consultant engineer on the project was Sir Alexander Gibb & Partners. Eighty thousand tons of plant and construction materials (including 36,000 tons of cement) were shipped out from Europe in the difficult post-war period. They were then hauled 1,200 kilometres (750 mi) by rail from Mombasa to Jinja. The dam was completed in three years, ahead of schedule in 1954, submerging Ripon Falls.[3]

It supplies electricity to Uganda and parts of neighbouring Kenya and Tanzania. Maintenance and availability of the station declined seriously during the government of Idi Amin.

The rating of the Nalubaale power station is 180 megawatts (MW). Originally it was designed for ten turbines rated at 15 MW each (for a total of 150 MW. The station was refurbished in the 1990s to repair the accumulated wear from a decade of civil disorder. During the repairs, the output power of the generators was increased, bringing the Nalubaale Power Complex's generating capacity to 180 MW.[4]

Operations

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The Uganda Government, through the Uganda Electricity Generation Company (UEGCL), a 100 percent parastatal, awarded a 20-year operational, management and maintenance concession to Eskom Uganda Limited, a subsidiary of Eskom, the South African energy company, to cover both Nalubaale Power Station and the adjacent Kiira Power Station. The concession agreement commenced in 2002. The electricity generated here, is sold to the Uganda Electricity Transmission Company Limited (UETCL), the authorized single buyer. UETCL in turn sells the power to Umeme, the energy distributor.[5]

On 31 March 2023, the 20-year concession with Eskom for both dams expired and was not renewed. Uganda Electricity Generation Company Limited (UEGCL) took over the management of the power stations and absorbed 93 percent of Eskom Uganda staff, effective 1 April 2023.[6]

Maintenance

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In 2021, Eskom Uganda Limited hired Babcon Uganda Limited at a cost of USh888 million (approx. US$251,000) to repair and strengthen the powerhouse staircase to Units 1, 5 and 9. The deterioration of the staircase is blamed on Alkali Silica Reaction (ASR), which results when water reacts with concrete, over time, causing expansion of the concrete and loosening of attached hardware.[7]

In September the same year, Sinohydro Corporation Limited completed renovations to the dam's structure. The repairs that lasted nearly one year, were meant to stop water leakages due to "deterioration of grout curtain". It is expected that the repairs, last carried out in 1999, will give the dam at least another 20 years of life. The repairs cost USh11.6 billion (US$3.3 million).[8]

In September 2022, Eskom Uganda spent UGX:6.84 billion (approx. US$1.8 million) to replace three of the ten generator transformers. The transformers to units 3, 5 and 6 "were past their service life expectancy" and were replaced. The transformers from units 1 to 4, step up voltage from 11kV to 33kV, while those from units 5 to 10 step up voltage from 11kV to 132kV. The power at high voltage is then transmitted across the grid. Transmission of power at high voltage over long distances reduces power losses.[9]

Owen Falls Extension

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In 1993 work started on the Owen Falls Extension project, a second powerhouse located about 1 km from the 1954 powerhouse. A new power canal was cut to bring water from Lake Victoria to the new powerhouse. Major construction was completed in 1999 with first power from the project from two units in 2000. The extension has space for five hydroelectric turbine generators with four installed as of 2001. Each unit at the extension has a capacity of 40 megawatts. During official opening ceremonies in 2003, the extension was named the Kiira Power Station. Design and project management of the extension project was by Acres International of Canada, now known as Hatch Limited.

Eskom Uganda operates Nalubaale Power Station as a concessionaire. They regularly clear debris water hyacinth from the intakes of the stations.[10] Further downstream, the 250 MW Bujagali Hydroelectric Power Station was constructed between 2007 and 2012.

Lake Victoria water levels

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Since January 2006, hydroelectric generation at Nalubaale and Kiira stations has been curtailed due to a prolonged drought and low level of water in Lake Victoria. The hydrology of Lake Victoria has unusual features.[11]

In 2006 there was a release of secret documents from 1956 in Britain that indicated the British had considered using this dam to reduce the water in the Nile in an effort to remove Egyptian President Nasser. The plan was not carried out because it would have seasonally flooded land in Kenya, Uganda and Tanzania, reduced flows to a trickle in Sudan and the effect of shutting off the White Nile even to coincide with the seasonal lull in the Blue Nile would not have affected Egypt for at least 16 months.[12] Veto power over construction projects on the Nile River and its tributaries was granted to Egypt by the Anglo-Egyptian treaty of 1929, reinforced by the bilateral agreement between Egypt and Sudan signed in 1959. In 1959 upriver Nile states such as Uganda denounced this treaty purportedly claiming virtually all of the waters of the Nile to themselves and leaving none to the upriver states. The countries along the White Nile excluding Sudan seek to create a unified international legal framework for the basin and for the time being respect keeping lake levels virtually unaltered so as not to upset their own eco-systems and established patterns of crop production and livestock raising.[13]

Developments

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In October 2024, Jan Sadek, the ambassador of the European Union to Uganda, announced an economic package valued at €170 million (UGX:680 billion), to rehabilitate, stabilize and prolong the life of both Nalubaale and Kiira dams. Of the total, €30 million is a grant from the EU to the government of Uganda. The remaining €140 million is a concessional loan from the European Investment Bank and the French Development Agency (FDA).[14]

See also

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References

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  1. ^ http://pubs.iied.org/pdfs/16030IIED.pdf [bare URL PDF]
  2. ^ "Map Showing Kampala And Nalubaale Power Station With Distance Marker". Globeed.com. Retrieved 7 May 2014.
  3. ^ Julian Bertlin, letter, The Times, 7 January 1995
  4. ^ Kasita, Ibrahim (3 February 2012). "Owen Falls Dam: Powering Uganda for Five Decades". New Vision. Kampala. Retrieved 20 October 2016.
  5. ^ Joseph Olanyo (5 August 2012). "Eskom To Invest US$20 Million On Nalubaale And Kiira Dams". The Observer (Uganda). Kampala, Uganda. Retrieved 10 September 2014.
  6. ^ John Odyek (27 March 2023). "Government Takes Over Management of Nalubaale, Kiira Power Stations". New Vision. Kampala, Uganda. Retrieved 1 November 2023.
  7. ^ Nelson Mandela (31 July 2021). "Eskom Uganda invests UGX. 888M to renovate Nalubaale Powerhouse Staircases". PML Daily. Kampala, Uganda. Retrieved 2 August 2021.
  8. ^ Hakim Kanyere (9 September 2021). "Refurbishment of Nalubaale power dam complete". Nile Post Uganda. Kampala, Uganda. Retrieved 13 September 2021.
  9. ^ BFUg (2 September 2022). "Eskom Uganda Invests Shs 6.84 Billion To Replace 3 Generator Transformers At Nalubaale Power Station". BusinessFocus.co.ug (BFUg). Kampala, Uganda. Retrieved 17 September 2022.
  10. ^ Kasita, Ibrahim (6 August 2012). "Uganda: Eskom Invests $15 Million In Power Stations". New Vision via AllAfrica.com. Retrieved 7 May 2014.
  11. ^ "Low Water Levels Observed On Lake Victoria". USDA, (Washington, DC). 26 September 2005. Archived from the original on January 9, 2006. Retrieved 7 May 2014.
  12. ^ "Britain had secret plan to cut flow of Nile River — newly opened official file". International Herald Tribune. Associated Press. 2006-11-30. Retrieved 2006-12-02.
  13. ^ Governing the Nile River Basin: The Search for a New Legal Regime, Mwangi S. Kimenyi and John Mukum Mbaku, Brookings Institution Press, 2015
  14. ^ Hakim Kanyere (22 October 2024). "EU Commits Shs680bn Toward Rehabilitation of Nalubaale Dam". Nile Post Uganda. Kampala, Uganda. Retrieved 26 October 2024.
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