Natural gas is simple to adore, with half the pollutants of coal, a cheaper price tag, and nearly no particles.
For many Asian countries, it is still the preferred fossil fuel. Some countries, like Brunei and Singapore, rely nearly entirely on it. Natural gas, a combination of methane and other vapors created from age-old biomass underground and marketed as a clean-enough “transition” fuel, has been a popular alternative, and its usage has been expanding at the cost of oil and coal.
Between 2011 and 2019, nearly 100 power facilities in the United States transitioned from coal to natural gas. In the following years, Asia is anticipated to follow suit.
However, the case for relying on fossil fuels, in the long run, is becoming increasingly weak. As costs fall, zero-carbon energy sources such as solar and wind are becoming more practical. With present rules, the US Energy Information Administration projects that natural gas-generated energy would reach a worldwide peak around 2030.
According to the International Energy Agency (IEA), natural gas power output must drop by 90% by 2040 in order for the world to achieve net-zero emissions by mid-century. Much will hinge on whether the Asia-Pacific area, which currently uses a lot of natural gas, can wean itself off of it in the coming years. By 2050, demand from the region may have doubled.
As a result of these demands, leading gas turbine manufacturers are constantly improving their technology to make them hydrogen-compatible. The world’s lightest gas combusts similarly to natural gas, creating waste heat that turns generators (much as in standard combined cycle plants), but without emitting carbon dioxide. This stipulation provides a lifeline to current natural gas plant investments.
“Because of the possibility to gradually replace natural gas with hydrogen, investments in gas power plants today will have exceptional asset resilience,” said Andreas Pistauer, head of generation at Siemens Energy Asia Pacific. He describes how “[this] eliminates the need to expend vast amounts of resources to create whole new facilities” while arguing for keeping natural gas plants with a hydrogen swap.
The majority of hydrogen generated today is produced using fossil fuels such as coal and natural gas, resulting in emissions. However, there has been a growing interest in more environmentally friendly hydrogen manufacturing processes. In a net-zero society, cleaner manufacturing methods like as ‘blue hydrogen’ and ‘green hydrogen,’ for example, are predicted to be widely used. Carbon emissions are absorbed and stored in the manufacture of blue hydrogen, whereas green hydrogen is produced using sustainable energy sources such as solar.
Pistauer is optimistic that such turbines will reap carbon savings in the short-to-medium term while also allowing time for the groundwork and infrastructure to be put in place for the smooth integration of hydrogen facilities in the long run, as he explains how this mode of hybridization supports the shift to low-carbon fuels.
Still, for the time being, progress will be sluggish. Green hydrogen is now priced between $3 and $7.50 per kilogram, which is significantly pricier than natural gas. With greater technology and economies of scale, its cost is likely to decline in the future years, although rapid expansion is not expected until around 2035.
Because power is required to manufacture hydrogen fuel from water in the first place, using hydrogen to generate electricity may raise some questions. However, according to Pistauer, hydrogen may be used to provide backup power for intermittent energy sources such as the wind and sun.
When it comes to complementing, or even enabling, the fast rise of renewable, but variable, capacity, the flexibility of gas power plants to deliver flexible load is critical. While efficient, this flexibility is also necessary for the system to accommodate huge amounts of renewable energy. The gas may also be stored for months, allowing for the utilization of extrasolar energy generated in the summer during the dark winter months.
There are also technical difficulties to contend with. Hydrogen burns at a temperature of 300 degrees Celsius higher than natural gas, making it more difficult to regulate. Some turbines may belch nitrogen oxides, a major source of urban air pollution and acid rain, due to the extreme heat.
Siemens Energy noted in a white paper that gas turbines may need to be changed or replaced to properly manage high hydrogen fuels. To guarantee safety, other sections of the power plant, such as pipelines and flame monitoring systems, may need to be tweaked as well. Each update will need to be site-specific and will necessitate a thorough investigation.
For the time being, corporations are concentrating on blending modest quantities of hydrogen into the natural gas feed of power plants, with studies now underway in the United States and Australia. Their projects tap into a broader industry and regulatory interest in experimenting with hydrogen transport in existing natural gas pipelines.
According to the European Association of Gas and Steam Turbine Manufacturers, Siemens Energy intends to supply 100% hydrogen turbines by 2030.
Meanwhile, natural gas appears to be here to stay. Natural gas is unlikely to be totally phased out by 2050, according to the IEA’s net-zero scenario. Natural gas demand in Asia-Pacific is likely to lead the post-pandemic recovery.
“Fossil fuels will continue to dominate baseload production in most Asian countries in the next years,” Pistauer said. “Natural gas, when locally accessible or imported as LNG, will play a critical role in meeting the rising need for reliable baseload power.”
Siemens Energy said it is tackling the problem of fossil-fuel emissions by upgrading equipment and digitizing its operations. Gas turbines can now convert roughly 35% of natural gas energy to electricity, while improved systems with over 60% efficiency are being developed. Siemens Energy, according to Pistauer, is also employing 3D printing to speed up the development and manufacture of innovative components and devices, such as higher-temperature-tolerance turbines.
Plant-emission carbon dioxide capture technology is also being developed. Despite the fact that it is costly and now used by no gas plants throughout the world, this might change if governments around the world re-invest in carbon capture technology.
The only thing left is to address methane leaks from natural gas production, storage, and transportation. Despite the fact that methane only lasts approximately a decade in the atmosphere, it is about 80 times more effective than carbon dioxide in terms of warming the Earth and now accounts for a fourth of current global warming.
Several significant emitters from Asia, including India, Iran, and China, did not join the promise, however, China has indicated it will explore how to reduce methane emissions, particularly from the natural gas industry, during the recent COP26 meetings.
At the last COP26, almost 100 nations singled out methane and vowed to reduce emissions by 30% by 2030.
The United States, which is now one of the largest emitters of methane gas, seeks to reduce its emissions by more than half by enacting stronger requirements on equipment updates and well monitoring. As a result of this policy, the government has removed almost 2% of methane-rich natural gas from its supply chain. In the European Union, similar restrictions have been proposed.
“The energy transition is a worldwide phenomenon that necessitates close coordination between governments, the commercial sector, and society as a whole,” said Pistauer, who added that hydrogen-capable gas infrastructure might help in the meanwhile as countries work toward more sustainable energy futures.
