NamPower plans to build one of the highest concrete faced rock fill dams (CFRD) in Africa. The Baynes Project will take six years to complete and has an installed capacity of 600 Megawatt.

The Baynes Hydropower Project, situated along the Cunene River, 200 km downstream of Ruacana is one of the long term projects in the feasibility phase, and essentially emanates from initial studies conducted on the Epupa and Baynes sites along the Cunene downstream of Ruacana between 1995 and 1998. The studies conducted revealed that while the Epupa Site was technically preferable due to greater storage capacity, the Baynes site would be less disruptive to the life of the indigenous Himba people, and would have lesser environmental impact.

The Baynes Hydropower Project was initiated after the Firm Power Contract (FPC) with Eskom expired in 2005 and could not be renewed due to a critical power shortage faced in South Africa at the time. Imports became significantly more expensive, especially during peak hours and consequently both the Angolan and Namibian governments agreed to study the Baynes option further.

The Permanent Joint Technical Commission (PJTC) appointed the Cunene Consortium (CC) to perform a Techno-economic Feasibility Study (TEFS) on the Baynes Hydropower Project, and Environmental Resources Management (ERM), to independently conduct the Environmental and Social Impact Assessment (ESIA), in parallel and in close consultation with the techno-economic study.

Studies of the three site alternatives for water levels 580, 560 and 540 metres above medium sea level (mamsl) has been concluded, which means that for the maximum level of 580 mamsl, the dam level will only reach the foot of the Epupa Falls. The CC has also presented a positive outcome of the preliminary findings of Phase 3 of the Techno-Economic Feasibility Study, and deliberated on the Draft Bi-lateral Water Use Agreement on the Cunene River which deals with issues such as the establishment of a Bi-National River Authority, the establishment of the Baynes Hydropower Company, concessionary agreements between Angola and Namibia with the Baynes Hydropower Company for the development, operation and maintenance of the power station.

It is envisaged that the Baynes mid-merit/peaking power station's capacity would be 600 MW which will be shared equally by Namibia and Angola. Like Ruacana Power Station, the new dam will function as a mid-merit peaking station, so that NamPower can avoid buying imported power during peak hours. During the wet season the Baynes Power Station will run at full capacity, while during the dry season the generators will generate at maximum during mid-merit/peak periods only whilst 71 MW would be generated during the off-peak periods.

Dam:

The structure of the dam consists of a rock fill embankment with a concrete face.

In total the rock fill will be 12 million cubic meters. The water face of the wall is lined with a concrete face that is about 80 centimeters thick at the bottom and around 30 centimeters at the top and provides the water tightness to the dam wall.

The maximum dam wall height at Baynes will be 200 metres; the reservoir will be 43 kilometres long and have a maximum width of 4 kilometres. The area inundated by the reservoir would be 57 km2 and will hold 2,650 million m³ of water which is about half of the river's annual runoff of 5,000 million m³.

On average, 159 m³/second will flow through the dam and in the dry season and during off-peak hours, a minimum flow of 50 m³/second will be maintained in order to sustain all the living organisms and to maintain a healthy ecosystem downstream of the dam.

The water head of Baynes will be an astonishing 187 meters, while the dam wall will be 200 meters high.

Although the capacity of the Baynes dam is smaller than that of Epupa's forseen 7,500 million m³, it has an annual average electricity generation of 1,610 GWh and is certainly not regarded as a small hydro power station. Kariba, one of the largest dams in the world has an installed capacity of 1,200 MW and an annual generation of 6,400 GWh.

Hydropower Station and Substation:

The hydro array at Baynes will consist of five Francis Vertical Axis turbines, two with a capacity of 71 MW and three 156.75 MW turbines. The Substation will be located nearby the power plant occupying an area of about 150,000m².

Construction:

The engineering and construction work is time-consuming. From the moment of commissioning which could be around 2014, the dam will take six years to be constructed. This means that Baynes will only start feeding power into the grid towards the end of the decade. .
By that time power demand will have risen significantly from the current 511 MW peak consumption, so it is important to note that Baynes is just one of the generation projects that NamPower is embarking on. The Kudu gas power station in Luderitz or a coal fired station at the coast will likely be finished several years before Baynes. .
The construction work will commence with excavating a bypass tunnel on the Namibian side where the rock is most competent (see visual). Next, two coffer dams will be constructed upstream and downstream from the site, so that the area in between is laid dry. The coffer dam will also serve as river crossings during construction. .
A 1.3 kilometer overflow canal or spillway will be constructed to prevent the dam from overtopping and which is required for the protection of the dam wall. This canal is partly lined with concrete and has cascades to slow down the flow of water. .
Construction roads need to be built and the hydropower station will be constructed in all likelihood to straddle the border of the two countries. The dam wall itself will form a bridge between Angola and Namibia.
There will most likely be two 400 KV lines evacuating the power from the gorge to Namibia and Angola.

Long-term benefits:

Hydropower needs specific mention as a renewable source of energy and traditionally the only contribution to greenhouse gasses by hydropower projects are from plants decaying within the dam basin. The Baynes Hydropower station is a very valuable generation asset that has the potential of supplying Namibia and Angola with reliable, clean electricity for generations to come, making the estimated investment of US$1.2 billion well worth it.