3. Transmission Line
3.1 500 kV Connections to the Thai Grid
A 500 kV double circuit overhead power transmission connection will be provided to deliver power from the 500 kV switchyard of the Power Plant to the Thai Grid System at the Thai-Lao border approximately 67 km distant from the Power Plant. EGAT is responsible for completing the connection between the Thai-Lao border and the 500 kV connections at the Mae Moh Substation, in a total distance of 250 km.
The transmission lines will be designed and constructed in accordance with EGAT standards. Each phase of the circuits will consist of 4 conductors, designation 1272 MCM ASCR.
3.2 115 kV Connections to the Lao Grid
A 115 kV double circuit overhead power transmission connection will deliver power to a new 115 kV Substation to be constructed near to Hongsa Town. The 115 kV Hongsa Substation will supply power within the Hongsa Valley and to the Lao northern region through Luang Prabang 2 Substation to be constructed by other parties. Power will be delivered to Luang Prabang 2 Substation by double circuit 115 kV transmission lines. Total route length from the Power Plant to Luang Prabang 2 Substation is approximately 115 km. For each circuit, one ACSR 795MCM conductor will be used per phase.
The indicative route for the 115 kV transmission connection from Hongsa Substation to Luang Prabang 2 Substation and the 500kV transmission line from the Power Plant to the Thai-Lao border are shown in the Figure below.
4. Fuel Supply
4.1 Lignite Mine
Lignite is used as primary fuel and diesel is used for start-up, flame stabilisation, and low load operations. Lignite will be supplied from the Mine located adjacent to the Power Plant. There are over 700 million tonnes of lignite in the Hongsa Basin, and within the Planned Mine Area, there are approximately 341.26 million tonnes of lignite reserve. The Mine is expected to produce and store fuel in a stockyard adjacent to and northeast of the Power Plant. The stockyard will serve as a lignite