Bui Dam to alternate between hydro and solar energy

In a novelty that will help extend the lifespan of the Bui Dam and make it more efficient, the dam is to be configured into a dual source energy generator to produce electricity from solar in the day and hydro in the night.

The project to add solar generation to the dam will help increase the Bui Dam’s installed capacity to 650 megawatts (MW) through the addition of 250MW.

The Chief Executive Officer of the Bui Power Authority, Mr Fred Oware, told the GRAPHIC BUSINESS that feasibility work for the project and compensation payouts to affected farmers had since been completed, paving the way for construction of the first phase to begin “any moment from now.”

“The switchyard itself is 250MW but we will be doing it on phase by phase basis. We want to start with 50MW and the rest will depend on demand,” Mr Oware said.

With national installed capacity exceeding demand, he said the authority would invest on new generation “as and when the Electricity Company of Ghana (ECG) give indications that they have capacity to absorb more.”

On how much it will cost to execute the project, he said the authority was yet to finalise those details.

While admitting that it cost an average of US$1 million to install a solar plant to generate every one MW of power, the CEO said the cost of the Bui solar project “will depend on who is doing it, the terrain of the land, where you are buying your photovoltaic (PV) cells from, among other things.”

A successful execution will add solar to Bui’s energy mix while increasing national generation from that resource.

Complementary role

In spite of being on the drawing board since 1966, the development of a hydropower scheme on the Black Volta River at the Bui Gorge started bearing fruits in 2007, when the Bui Power Authority was established to oversee the Bui hydroelectric project.

After six years of construction, the generation station was completed and inaugurated on December, 2013. This added 400MW of installed capacity to the national grid.

Given that the plant is a peaking one – does not operate 24/7 – the CEO of Bui Power Authority said his outfit was finding innovative ways to properly utilise the water to ensure for efficiency purposes.

“When the sun is up during the day, we use the solar. In the night when you cannot use the solar because the sun is gone to sleep so to say, you use the hydro so that we can manage the resources well than what we are doing right now,” he said.

Cost efficiency

The Executive Director of the African Center for Energy Policy, Mr Benjamin Boakye, explained that the solar project would make it possible for Bui to run non-stop.

“At the moment, Bui is a peaking plant; they turn it on as and when there is high demand for power and so it comes on like eight hours in a day.

“So what they want to do is to try and reserve the water levels so that they can run 24 hours,” he added.

He said it was possible that the authority would save some costs through the switch system.

“I think they will save some costs because it will be close to their transmission lines. I do not know how they want to configure it but I will assume that they are doing it close to the Bui Hydro transmission system, then they will not have to use a new transmission system and all that,” he said. — GB