Energy-saving Action Plans

According to the inventory data, 35% of the OUCC greenhouse gas emissions came from electricity. As a response, we set a "power-saving" goal by promoting a series of power-saving measures, looking for suitable fuel- and steam-saving solutions. With effective management, the actual annual power saved was about 10.4644 million kWh in 2024, with a 2.37% power-saving rate.

Actively Promote Energy Saving at Linyuan 

The feasibility of a high-efficiency low-carbon heat and electricity cogeneration system at the Linyuan Plant is being evaluated, in the hope that the electricity and steam will fulfill all the requirements for production. 

In accordance with the large-scale electricity user clause, the company purchased approx. 7,675,000 kWh of renewable energy in 2023, representing 10% of the contracted capacity. The company's mandatory installed capacity in 2024 is 5,115.06 kWh. In addition to 108.78 kWh of the solar system installed, the company also purchased 6,160 kWh of renewable solar power and certificates, equivalent to 7,700,000 kWh, for a total committed capacity of 6,268.78 kWh, meeting regulatory requirements.

In addition, OUCC makes full use of technological advantages to promote clean processes, coupled with a cloud based "plant power monitoring system platform" to monitor energy utilization at plant area with the structured approach in search of energy-saving opportunities to enhance energy efficiency and carbon reduction; while at the office area, we promote electronic administrative operations, photocopying control and paperless systems to effectively reduce carbon emissions and improve operational efficiency.

OUCC's Linyuan Plant has changed the fuel of the coal fired furnace and the regenerative thermal oxidizer (RTO) systems to clean low-carbon fuel (natural gas). We also installed high-efficiency waste heat recovery technology to reduce fuel consumption and environmental pollution.

Expected Benefits

• Converting the medium-heat heating furnaces and the regenerative thermal oxidizer (RTO-I/RTO-II) incinerators to natural gas burners and deactivating the diesel pumps are estimated to save 8,169 kWh of electricity and reduce diesel consumption by 600 kL annually. The projects were completed by the end of January 2021.
• 2021-2024: The cumulative carbon reduction was about 2,104 t-CO₂e。

  To beautify the factory surroundings as well as to reduce the long-term problem of flooding, the paving at production processing sites of Linyuan were completed, and underground discharge pipelines were laid and modified at the EOG plant, which included the following:

1. Rain and polluted water diversion was established at the leaked wastewater collecting pit of EO loading station / EG / EA filling stations and the recovery system. Modifications were made to the draining chutes to ensure the separation of rain and polluted water.

2. The drainage system surrounding the plant was reconstructed and a flood retention pond was built.

Expected Benefits

• The paving at each processing area optimizes the surrounding of the Plant area.
• Both the rain and polluted water were diverted to reduce environmental and industrial safety issues, reducing the occurrence of penalty incidents.
• The drainage system surrounding the plant was reconstructed, which solved the long-term flooding problem, and a flood retention pond was also built to cope with the impact of climate change.

Due to the outdated design of the gas circulating cooler and cooling water tower of EOG plant, there was no way for maintenance personnel to get into the tower to fix an abnormal fan on account of the high temperature resulted from the lack of interior isolation. It would cause the cooling water temperature to rise and require the reaction zone to reduce production.
After reconfirming the overall water distribution and thermal loading of EOG, the water supply of circulating water coolers (TT-201N/TT-201) were replaced by the #2 cooling water tower (where the inside can be isolated and repaired). 

Expected Benefits 

• The annual electricity saved totaled 6 million kWh, with NT$20.15 million saved.
• The system reduces greenhouse gas emissions by approx. 3,218 t-CO₂e per year.
• 2019-2024: The cumulative electricity saved totaled 36 million kWh, with NT$91.76 million saved, and greenhouse gas emission of 19,308 t-CO₂e reduced.

(1) Photovoltaic system:  Installment of a photovoltaic system on the rooftop of the semiconductor CO₂ plant at Linyuan was completed by Q1/2023, with capacity of 108.78 kWp and annual average power generation of 153,000 kWh. As renewable energy is self-generated and used, the renewable energy certificate can be obtained. 

(2) Co-generation system: Become partial self-sufficiency in terms of electricity, re-adjust the heat and electricity ratio, and plan a high-efficiency and low-carbon co-generation system in response to future energy structure changes.

(3) Medium and long-term plan: Actively evaluate options such as “setup of renewable energy facility (rooftop photovoltaic system),” “purchase green power and RECs,” and “setup of energy storage equipment.” We procured green power and RECs per year starting December 2023 to conform with the regulated requirement of 10% contracted power capacity of green energy.

In order to save energy, the excess steam emitted at Linyuan Plant will be recovered and reused to replace the old screw type chiller unit for air conditioning at EOG control room, the laboratory and R&D buildings, with estimated annual electricity savings of 2.07 million kWh, and reduction of 1,040 t-CO2e per year.
The cumulative energy savings from 2021 to 2024 amounted to approximately 8.28 million kWh, resulting in a reduction of 4,160 t-CO₂e.