Failures of overhead power lines caused by gales, hurricanes or storms very often transform into numerous network failures of a significant scale and extent. The end result of the failure is the lack of power supply to thousands of electricity consumers. During the failure of the 110 kV power line Goleniów - Moracz #EltelNetworksTeam professionally rose to the occasion and despite the difficult terrain conditions (marshy forest areas) and unfavourable weather conditions, it completed the entrusted task - removing the power failure - in a record time of 36 hours!
Marek Zglejc
Construction manager
Eltel Networks Energetyka SA
FACTS
Investor: ENEA Operator Sp. z o.o. Network Maintenance Department
Location: Miękowo, West Pomeranian Voivodship
Investment cost: PLN 464.365
Completion: 2022
LINE DETAILS (Failure range)
- replacement of 3000 m of OPGW wire
- assembly of 2 fibre optic joints
- taking measurements of optical fibres
- replacement of 1 tower with foundations
- restoration of the ring earthing
- repair of 3 steel structures
- repair of work wires in two spans
CHALLENGE
ENEA Operator Szczecin asked us if we were able to remove the failure caused by bad weather conditions in the vicinity of tower no. 32 of the 110 kV Goleniów - Moracz overhead power line in the shortest possible time. After an on-site visit by Eltel Networks field employees, the client was informed about the scope of work to be performed in order to immediately restore the power supply and about the time to remove the failure (maximum 48 hours). For the client, the time of re-energizing the power line and the precise determination of the required scope of work for the further safe operation of the high-voltage (HV) line played the most important role.
This is due to the fact that 110 kV overhead lines are a very important element of the power grid infrastructure. It is a preliminary distribution network, and any reduction of interruptions in electricity supply is a priority in emergencies.
EFFECT
The time to remove the power failure was a record 36 hours. During this time, we managed to mobilize equipment, brigades, necessary materials and remove the damage that threatened the stabilization of the energy distribution network. During emergency repair of the overhead power line:
- fallen trees were removed from the work and lightning wires of the 110 kV Goleniów – Moracz power line
- protection of the work wires was commenced for the time of replacement of tower stand no. 32
- the damaged tower stand no. 32 was dismantled
- assembly of the new EJ 24P+0 tower was carried out, including the adjustment of the foundation spacing to the new tower
As a result of the weather anomalies, fallen trees also damaged the work wires and the OPGW wire. The work wires were repaired by using an insert with dedicated press connectors and repair braids. The OPGW wire was replaced in the entire section with a length of 3000 m. The last stage of works included the replacement of the existing structural elements of the E24P tower no. 31, 33 and 36 of the 110 kV Goleniów - Moracz power line, which were also damaged as a result of fallen trees.
Eltel Networks restored the power supply to the 110 kV Goleniów - Moracz overhead power line effectively, safely and in a very short time (less than two days from receiving the order). The failure occurred in hard-to-reach, marshy forest areas, and additionally, our electricians and construction workers worked in particularly unfavourable weather conditions until late at night to complete the entrusted task on time and restore power to thousands of customers.
During the emergency repair of the 110 kV Goleniów - Moracz overhead power line, we gained practical experience of working under strong time pressure, which resulted in obtaining further orders to remove failures in the area of ENEA Operator Szczecin's distribution networks.
