T&D
The Ceylon Electricity Board (CEB) of Sri Lanka has produced a master plan to maximize the effectiveness of its T&D system.
The plan stresses reducing the system losses currently running at 22 per cent. This loss represents wastage of 500 GWh. These system losses come from shotcomings in the T&D systems, which are not sufficiently equipped for instant transfer of electricity from the hydropower plants in the country’s hills and the thermal plants closer to the capital city. Sources claim that extending the transmission system and reconfiguring the the primary (33 kV and 11 kV) and the secondary (400/230 V) distribution systems should minimize losses and improve quality and reliability.
The current grid has some areas that are nearly 50 years old. Sri Lanka’s first transmission line was built at 66 kV, which was outdated even when it was built. The next batch of lines were built at 132 kV. The plan is to replace these lines with 400 kV lines, which would reduce transmission losses, have a higher load capability, better voltage regulation over long distances, and would be cheaper per MWe delivered than 220 kV lines. In addition, Sri Lanka has one of the highest rates of lightning strikes in the world, and the 400 kV lines would be best able to deal with this.
It is also argued that wood distribution poles be used to replace concrete poles, given the high lightning frequency.
The medium-term plan would also have the goal of building a national grid.
The CEB acts as the national supply authority, concerned with generation and transmission, with distribution shared between CEB and Lanka Electricity Company (LECO).