Electricidade de Moçambique (EDM) is conducting a feasibility study that could lead to the construction of two new hydropower plants on the Revúe river basin in Manica province — the Tsate plant, with a capacity of 50 megawatts (MW), and Mavuzi II, with an estimated capacity of 28MW.
According to Stélio Leitão, EDM's Director of Production for the Central and Northern regions, rising electricity demand is increasing the urgency to develop new hydropower infrastructure. The existing Chicamba and Mavuzi plants are no longer able to meet demand, driven by the continuous growth of new industries, residential connections, and other consumers.
To safeguard storage capacity at both reservoirs, Leitão called for regular bathymetric surveys at Chicamba and Mavuzi. The objective is to assess the accumulation of soil, sand, waste, and organic matter on the reservoir floors and determine whether dredging is required to restore storage capacity.
EDM is also grappling with the challenge of restoring equipment availability and generation capacity at the plants, both of which have been affected by pollution from artisanal gold mining along the rivers that feed the Chicamba reservoir. Leitão noted that the suspension of mining activities — ordered by the Council of Ministers at the end of September last year — combined with heavy rains from December onwards, has contributed to an improvement in water quality.
Despite this improvement, contamination of the filtration elements at both plants caused frequent short-term shutdowns of generating units for maintenance, driving up production costs. 'At the turbine level, water contamination caused surface wear, the impact of which could be severe in the medium to long term,' Leitão said.
He added that the influx of turbid water into the reservoir led to sediment accumulation, further reducing the dam's storage capacity. The plants also experienced repeated maintenance-related stoppages and production restrictions due to low water levels at the Chicamba dam.
With water quantity and quality now improving, Leitão said maintenance shutdowns have decreased and plant output has increased. 'In terms of generation capacity, with the Chicamba dam at its maximum storage level, the Mavuzi and Chicamba plants together contribute approximately 50% of the electricity consumed in Manica and Sofala provinces,' he said.
The Chicamba plant has an installed capacity of 48MW and four flood-discharge gates, and is currently generating 25MW during peak hours. The measure forms part of EDM's broader efforts to rationalise the use of available water in the reservoir.
Source: Diário Económico
Original article: https://www.diarioeconomico.co.mz/?p=531156
