中央研究院淨零科技

Background

For a long time, thermal power generation has accounted for more than 80% of Taiwan's total power generation ^[1] , providing a stable power supply, yet at the same time, thermal power has become one of the main sources of carbon emissions in Taiwan. At present, coal-burning power generation accounts for approximately 50% of thermal power generation and about 30% of Taiwan's carbon emissions. With mature technology, both natural gas power generation and coal-fired power generation can provide stable and large amounts of baseload power. However, the carbon emissions of natural gas power generation are 44% of those of coal-fired power generation ^[2] . Hence, in recent years, the primary energy transition strategy adopted by the government of Taiwan has been to reduce coal-fired power generation and increase natural gas power generation, so as to reduce carbon emissions in the power sector ^[3] . However, in the long run, natural gas power generation still emits carbon. It is thus essential to effectively reduce carbon emissions from natural gas power generation (i.e., changing the approaches of gas-fired power generation) to ensure that natural gas remains an important energy source for Taiwan.

Two possible technologies can help us change conventional gas-fired power generation. The first is carbon capture and storage (CCS), which captures the carbon dioxide produced during the gas-burning process and stores it in carbon sequestration sites. This approach can reduce carbon emissions; however, identifying suitable carbon sequestration sites in Taiwan may be challenging, and the amount of carbon to be stored remains unknown. Therefore, there is a high degree of uncertainty with this technology. Another possible technology is methane pyrolysis (Methane Pyrolysis to Power, MPTP), which cracks natural gas into hydrogen and solid-state carbon, utilizing the hydrogen for combustion to generate electricity, thereby addressing the carbon emission issue associated with natural gas power generation. Academia Sinica is hence actively developing MPTP technology, hoping to meet the dual goals of stable power supply and net-zero carbon emissions.

Introduction of the technology

"MPTP Technology" combines two technologies to remove carbon, produce hydrogen and use hydrogen for power generation. At the power plant, natural gas is decomposed into hydrogen and solid carbon under anaerobic conditions through a process called methane pyrolysis (Figure 1). The generated hydrogen is directly delivered to the gas turbine for combustion and power generation on-site, thus requiring almost no transportation or storage. This process does not emit carbon dioxide and helps solve the problem of expensive hydrogen transportation and storage. It is a good approach to generate zero-carbon electricity and can be regarded as an application of hydrogen power generation.

^[1] Since 2000, thermal power generation has accounted for 75%-80% of total power generation in Taiwan. After 2015, as the proportion of nuclear power dropped from 16% to 14% and continued to decline, thermal power generation has consistently accounted for 80% of total power generation over the past decade.

^[2] Important Policies, Ministry of Economic Affairs https://www.moea.gotw/MNS/populace/Policy/Policy.aspx?menu_id=32800&policy_id=9

^[3] National Council for Sustainable Development, Council Executive Yuan (2024). Taipower: Taichung Power Plant's phase II gas-fired units are expected to reduce air pollution, carbon emissions and coal consumption.https://ncsd.ndc.gov.tw/Fore/News_detail/cc973575-4233-4c13-8df7-69a2dfeba3d2