The olefins plants also yield various by-products, such as pyrolysis gasoline, mixed C4, tail gas, cracker bottom, and hydrogen. GC enriches the values of these by-products through synergy with the refinery and aromatics plants. For example, pyrolysis gasoline is turned into aromatics products; cracker bottom is mixed with fuel oil into higher valued products; hydrogen is used in the refinery as a substitute for hydrogen produced by the Hydrogen Manufacturing Unit (HMU), which otherwise requires a higher production cost; and mixed C4 is turned into butadiene and butene-1 at the by-product value-added plant. GC also produces utilities (electricity, steam, and industrial water) for our own use, which enhances its production capability and competitiveness. Surplus volumes of the utilities are sold to Electricity Generating Author i ty of Thai land (EGAT) and neighbor ing petrochemical plants. GC has five olefins plants. In 2021, olefins plant unit 4 (Olefins Reconfiguration Project) began commercial production project, and increase overall nameplate capacity to 3,738 thousand tons per year. The details are shown in the table below: FEEDSTOCK SOURCING The primary feedstocks for GC’s olefins production are ethane, propane, LPG, and NGL, which are natural gases. In 2021, GC secured 65% of these feedstocks from PTT and used more internally produced feedstocks. While GC relied heavily on PTT, PTT also has a high capacity to deliver these feedstocks as it operates five gas separation plants in Map Ta Phut, which are unlikely to halt production at the same time. PTT also has feedstock reserves, which enable PTT to deliver feedstocks to its customers. In addition, GC and PTT also work closely to ensure feedstocks are delivered as planned. GC has also entered into a long-term olefins purchase agreement with PTT to procure feedstock for its olefins plants at market prices. In addition to the aforementioned feedstocks, GC also uses light naphtha and LPG, which are by-products from GC’s refinery and aromatics plants. GC’s feedstock security derives from flexibility in feedstock choice, which allows GC to produce olefins products with consistently high stability and meet the needs of downstream industries. In 2021, GC’s olefins plants use natural gases and naphtha approximately in a ratio of 80:20. POLICY AND MARKETING GC’s policy is to build its competitiveness on par with international standards by using diverse feedstocks, controlling costs to a competitive level, and increasing business opportunities from upstream to downstream businesses to give GC stability and management options. GC’s domestic and international competitive capabilities have allowed for more agile marketing polices and increased options in selling its products, especially during times of high volatility. In addition, GC seeks opportunities to create the synergy within PTT Group, such as by sourcing quality feedstock at competitive prices and exchanging knowledge to jointly develop best practices. Olefin products are primari ly used to produce downstream petrochemical products for expanding and value adding to olefins products, while the rest is sold to its affiliated and domestic customers, such as GC Glycol Co., Ltd. (Glycol), HMC Polymers Co., Ltd. (HMC), Vinythai PLC (VNT), GC Oxirane Co., Ltd. (GCO) and other companies in Map Ta Phut Industrial Estate. GC’s domestic market shares for ethylene and propylene are 38% and 48% respectively. The remaining products are exported. GC continuously seeks for opportunities through corporation with PTT groups to strengthen the marking strategy and distribute these products in worldwide market. Company Product Nameplate Capacity (thousand tons per year) GC Ethylene 2,876 Propylene 762 Butadiene 75 Butene-1 25 41 BUSINESS OPERATION AND PERFORMANCE CORPORATE GOVERNANCE FINANCIAL REPORTS AND FINANCIAL STATEMENTS APPENDIX