CONCO is due to complete a major turnkey project undertaken for Tanzanian Electricity Supply Authority (TANESCO), before the end of May. The company has been constructing and rehabilitating several substations in the Kilimanjaro and Arusha areas of the country.
The main objective of the project is to improve the quality and reliability of the power supply of TANESCO’s 33/11-kV distribution system and to capture the unmet power demands in the main supply centers of Arusha and Kilimanjaro.
Under the World Bank-funded Tanzania Energy Development and Access Project (TEDAP), CONCO is required to adhere to International Electrotechnical Commission (IEC) standards. Equipment was imported from manufacturers in Spain, India, Germany, France, Italy and South Africa to meet the high standards.
Other factors such as cable size needed were given careful consideration to ensure the correct current carrying capacity due to present and future electricity demand. The majority are indoor substations housing 33kV Gas Insulted Switchgear (GIS) and 11kV Air Insulated Switchgear (AIS), with the exception of the outdoor transformers.
During the new construction works and dismantling of the old equipment, temporary measures were in place to ensure power supply outages were kept to a minimum, such as temporary cable connections between incoming lines and power transformers, and step-by-step changeover from old to new transformers, to name a few. Where substations were rehabilitated, it was also necessary for CONCO to determine the usefulness of existing equipment and transport it to TANESCO’s storage facility.
“It has logistically been a challenge to manage and co-ordinate a project of this nature,” said CONCO Project Engineer, Eugene Marais, “particularly with all substations being constructed in parallel and in most cases within the existing live substations. The substations were designed from the ground up and varying soil conditions and altitude meant that each substation was not merely a replication of each other; each site layout was different. For example, in the case of the substations near Kilimanjaro, seismic activity had to be taken into account particularly due to the earthquake that occurred in the past, which was as recent as 2016, just 80 to 100 kilometres from our nearest site.”
“A project of this complexity would not have been possible without the assistance and guidance of the consulting firm, Fichtner, as well as our team headed up by our country manager Mr Derek Phillips, based at our Tanzania office in Dar-es-Salaam. We are indebted to TANESCO for entrusting this very important project to CONCO,” concluded Marais.