The Akosombo Lake is projected to record a poor inflow next year, and that will affect the amount of electricity generated by the hydroelectric dam, the Volta River Authority has said.
The Authority's Chief Executive, Kweku Andoh Awortwi, told the B&FT that the historical pattern of the lake suggests an average to poor inflow next year.
“We have had four very good inflow years since 2007, and we knew it was just a matter of time before we had another bad year. This year, our current inflow is half of the long-term average. So it's not just an average year, but a poor year. What that means is that if we have another poor inflow next year, we will have problems,” he said.
“We should anticipate a poor inflow next year looking back on the patterns year-on- year. We are likely to have an average or below average year. If that happens and we don't do things to protect the lake, we will have real problems in 2015.”
Mr. Awortwi said the seasonality of water in the Akosombo Lake and high generation of hydro -electric power from the dam threatens its long-term sustainability, forcing the Authority to resort to generating more thermal power in order to preserve the lake.
“In the short-term, we are actually seeing a different issue. We have been over-generating the hydro in the last three years thumb is the Akosombo reservoir has three to four good years, followed by two or three bad years. If you look back in history, you will see it.”
The country currently generates the bulk of its energy requirement of 1,800 megawatts from hydroelectric sources — mainly Akosombo (1,020 megawatts), Kpong (145 megawatts) and recently Bui (133 megawatts).
The Authority is however taking steps to avert any impact from a potential shortfall of water inflow in the lake come next year. “We really have an obligation to the hydro. The first thing we will do is to run a lot less hydro than we planned.
“We have run a lot of simulations to see the probability [of a shortfall] and put in place mitigation measures so that if we have a bad year in 2014 we will be protected. We are deploying some of the emergency plants to run at different times at peak hours to preserve the hydro."