Electricity Generating : 15 August 2022 Notification of Commercial Operation Date of Nam Theun 1 Hydropower Project under Power Purchase Agreement with Electricity Generating Authority of Thailand

No. EGCO 110/160

Date : August 15, 2022

Attn : President of the Stock Exchange of Thailand

Subject : Notification of Commercial Operation Date of Nam Theun 1 Hydropower Project under Power Purchase Agreement with Electricity Generating Authority of Thailand

The Electricity Generating Public Company Limited ("EGCO") would like to inform the Stock Exchange of Thailand that Nam Theun 1 Hydropower Project ("the Project") managed by Nam Theun 1 Power Company Limited, a 25% ownership interest of EGCO, commenced its Commercial Operation to supply electricity to Electricity Generating Authority of Thailand ("EGAT") on August 12, 2022.

The Project is a reservoir hydro power plant, located on the Nam Kading River in Bolikhamxay Province, Lao PDR, and consists of 3 units with the total installed capacity of 650 MW. The Project sells 514.3 MW electricity output to EGAT and 130.8 MW electricity output to Electricite Du Laos ("EDL"). The Power Purchase Agreements with EGAT and EDL were signed for 27-year term.

The Project will contribute additional stable revenue sources to EGCO, starting from the 3rd quarter of year 2022 onwards and an increase of EGCO's renewable portfolio, gearing to the target of 30% of further renewable energy in 2030. Apart from this, the Project will promote the reliability of the national grid and consumption of clean energy. Also, it helps reduce the CO2 emission aligning with EGCO Group's initiative for Cleaner, Smarter and Stronger to Drive Sustainability Growth, supporting the target of carbon emission intensity by 10% in 2030 towards carbon neutral by 2050.

Please be informed accordingly and kindly disseminate the information herein to investors.

Yours sincerely,

Thepparat Theppitak

President

Corporate Secretary Division

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