Nuttachat Charuchinda

National Power Supply Co., Ltd. builds, owns, and operates power plants. It specializes in coal, diesel, and nuclear electricity generation. The company was founded on July 7, 1995 and is headquartered in Srimahaphote, Thailand.

PTT Aromatics & Refining Public Co. Ltd. manufactures cyclic organic crudes and intermediates. The company's principal activities are aromatics and refinery businesses. It supplies and refines petroleum products, such as liquefied petroleum gas, light naphtha and reformate, middle distillates including jet fuel and diesel and heavy products including fuel oil. The group is also engaged in the production and sale of aromatics products, which includes benzene, paraxylene, orthoxylene, toluene and mixed xylenes. The company was founded on September 13, 2007 and is headquartered in Bangkok, Thailand.

Bangkok Polyethylene Ltd, a subsidiary of PTT Public Co., Ltd., is an Energy Services Contractor operating in the oil and gas industries for over 20 years. The company is based in Sathorn, Thailand. The Thai company, established in March 2000, has a close collaboration and working relationship with major players in the region. With a workforce of 700 to 1000 personnel, Bangkok Polyethylene provides engineering and technical services across various projects. Bangkok Polyethylene was acquired by PTT Public Co., Ltd. on April 29, 2004 for $129.04 million.

PTT International Co. Ltd. provides petroleum exploration services. It offers petroleum products. The company was founded on October 1, 2007 and is headquartered in Bangkok, Thailand.

PTT Energy Resources Co. Ltd. is a Thai company that provides coal and mining services. The company is based in Bangkok, Thailand and was founded in 2009. The company is ultimately controlled by the Government of Thailand.

Bangkok Mass Transit Authority Ltd. provides local transportation services and is ultimately controlled by the Government of Thailand. The company is based in Bangkok, Thailand. Aek Angsananont has been the CEO of the Thai company since 2014.

Ritta Holdings Co. Ltd. is a construction company based in Bangkok, Thailand. The Thai company specializes in providing details such as direct cost, indirect cost, and overhead & profit necessary for construction through their bill of quantity (BOQ). The private company also engages in various activities such as planting mangrove forests in the Bang Khun Thian mangrove learning center area. The company was founded by five individuals, Mr. Suwat Chaopricha, Mr. Uthorn Phusitkanchana, Mr. Kamol, and others, in a no-frill shophouse in uptown Bangkok.