PTT invests in refining business through its 5 subsidiaries with total refining capacity of 1,040,000 barrels per day. PTT not only supplies crude which is procured from both domestic and international sources for all those refineries but also off-takes petroleum products from them, in term of PTT shareholding ratio in each refinery.
In spite of the existing up-to-date technology and high efficiency of production, PTT Group still attempts to enhance the competitiveness of its refining business by investing in related businesses which are petrochemical, lube base, electrical generation, marine shipping, and alternative fuels such as ethanol and bio-diesel.