As more countries across Asia prioritise decarbonisation and the integration of more renewable energy into their power grids, gas conversions of power plants are becoming an increasingly popular solution. Find out how gas converted power plants are helping to reduce emissions and provide the grid stability needed for energy transition across the region.
How gas firing power plants can support energy transition
In this episode of Rethinking Energy in Southeast Asia, Chuipin Chiu, Managing Director, Wärtsilä Taiwan and Welson Hong, Business Development Manager, Projects and Agreements, Middle East & Asia discuss the benefits of gas conversions and how it can support the ongoing transition towards cleaner and more efficient energy production. Hong starts by explaining how gas conversions of internal combustion engines can significantly reduce emissions. ‘‘Wärtsilä Energy has an extensive track record of successful conversion projects having completed gas conversions of over 100 engines worldwide.
The annual NOx emissions eliminated through our gas conversions is equivalent to the annual emissions of approximately 134 million cars. The annual greenhouse gas emissions eliminated through our gas conversions equals the annual emissions of approximately 1 million cars.’’
As well as reducing emissions, gas conversions reduce operational costs and increases fuel flexibility allowing the use of either gas, or both gas and liquid fuel.
The role of gas fired power plants in Taiwan
Taiwan plans to have an energy mix of 20% renewables, 50% gas fuelled energy generation and 30% coal fuelled energy production by 2025. The main drivers behind this are commitments to reducing air pollution and the planned phase-out of nuclear power.
As Chiu explains, ‘‘emission regulation is getting stricter, discouraging the use of liquid fuel, like heavy fuel oil, to generate power. At the same time, Taiwan Grid, Taipower Corporation, is also retiring the old nuclear power plants. Due to a reliable supply of natural gas and affordable gas prices, gas fired power plants are able to play an important role by replacing liquid fuel power plants and retired nuclear power plants to generate the required power.’’
Why the Ta-Yuan Cogeneration plant is converting to gas
In February 2021, Ta-Yuan Cogen Co. Ltd announced the signing of an EPC project with Wärtsilä. Wärtsilä will cover the engineering, shipping, all gas conversion parts, gas operation auxiliaries, gas safety equipment, electrical and automation upgrade and site work like installation and commissioning. Wärtilä is also guaranteeing the efficiency and power output of the gas engines after the conversion, providing absolute assurance to the customer.
The Ta-Yuan Cogeneration plant is located in Taoyuan City, Taiwan, and was originally equipped with three Wärtsilä 46 engines in 1998 running on heavy fuel oil. The gas conversion project will convert the engines to Wärtsilä 50DF dual-fuel engines providing a total power output of 32 MW. The electricity produced will be delivered both to the grid and to local industrial consumers, while the generated steam will be supplied to local companies.
Hong highlights four key benefits that will come from the gas conversion project.
‘‘The first benefit is the fuel flexibility. The heavy fuel oil engines will be converted to dual fuel engines and capable of running on either natural gas or diesel. In a normal situation the engines will run on natural gas but if there is an issue with gas supply, the engines are able to switch to diesel fuel without shutting down. This fuel flexibility will bring power stability to our Ta-Yuan Cogen customer.
The second benefit is lower emissions. Engines running on gas can reduce SOx and particulate emissions by 99%, NOx by 75-80% and CO2 by 20-25% compared to heavy fuel oil. As part of the decarbonisation strategy it will be more environmentally friendly and sustainable.
The third benefit is lower overall maintenance costs. The gas conversion will replace the engines’ major parts, obsolete electrical and automation system and provide new gas operation auxiliaries. The gas converted engines will start the engine maintenance from 0 running hour. Hence, the overall maintenance cost will be low after gas conversion project.
The fourth benefit is lower levelised cost of electricity (LCOE), which is achieved due to higher power plant efficiency after the gas conversion, fuel price difference, cheaper maintenance costs, and lower reagent costs like UREA for selective catalyst reduction (SCR) to reduce the NOx levels due to emission regulation. The gas engines will emit less emissions and requires lesser UREA for SCR to meet the emission regulation.
In short, the gas conversion will help to rejuvenate the power plant and make it more competitive and sustainable for the future.’’
Chiu adds that the gas engines’ ability to ramp up and down rapidly and provide full load capacity in 90 seconds will provide greater stability as more renewables are added to the grid.
The challenges and opportunities for gas conversion across Asia
Looking beyond Taiwan, Hong suggests that gas conversion has the potential to enhance the power grids of other countries across Asia. In countries like Timor Leste, where the baseload power generation is provided by diesel running power plants, there is an opportunity to both reduce emissions and lower the LCOE. However, the challenge for Timor Leste is a lack of LNG infrastructure.
The Philippines and Indonesia have smaller power plants running on liquid fuel, scattered across their many islands. Again, infrastructure needs to be addressed as the cost of LNG receiving terminals and long pipelines would be prohibitive for these smaller power plants. A more viable solution is to create a virtual gas pipeline using LNG ISO containers. LNG ISO containers can be transported via ships, barges, or trucks and therefore eliminating the need for a LNG receiving terminal or long gas pipeline.
Chiu concludes that gas conversions can extend the lifespan of engines running on liquid fuels by ten to fifteen years while also lowering the LCOE. This all makes gas conversions a strong proposition for Asia as it looks to reduce emissions and decarbonise its energy systems.
Find out more about gas conversion by watching the full webcast above.