HYDROCARBON GREENWASHING
Study reveals potential of blue hydrogen to play key role in energy transition
THE KENNEY UCP PLAN
The application of modern carbon capture technologies that limit emissions associated with the production of blue hydrogen can play a crucial role in its success as a 'bridging technology' in the energy transition.
Less expensive than carbon-neutral green hydrogen, and therefore better suited to being used at scale in the short term, blue hydrogen is produced from natural gas, with the resulting CO2 emissions captured and stored permanently underground in a process known as carbon capture and storage (CCS).
Recent studies have questioned the value of blue hydrogen in reducing emissions, chiefly because of inefficiencies in the production process causing CO2 to escape.
However, a newly published international study involving researchers from the University of Aberdeen and led by the Paul Scherrer Institute (PSI) in Switzerland and Heriot-Watt University has identified several key responsible factors in what causes CO2 to escape.
Crucially, the study has also shown that the application of modern carbon capture technologies can play a crucial role in mitigating this risk.
Professor Russell McKenna from the University of Aberdeen's School of Engineering is one of the researchers who have contributed to the study, which has been published in Royal Society of Chemistry's journal Sustainable Energy & Fuels.
He said: "Hydrogen is widely seen as one of the building blocks for a sustainable energy system, and if produced sustainably it represents a highly versatile means of long-term energy storage, with a variety of applications across the economy.
"The ultimate goal is to use green hydrogen, produced from renewable electricity thorough electrolysis, but this is currently prohibitively expensive.
"Blue hydrogen has been identified as a potential bridging technology, until green hydrogen can be scaled up and costs come down, however questions remain over its environmental impact and whether emissions associated with production cancel out any environmental benefit.
"What this study has shown is that the environmental impact of blue hydrogen depends on two key aspects—namely the amount of methane emissions in the natural gas supply chain, for example through gas flaring, and the CO2 capture rate in the plant.
"It identifies that if these parameters are made favorable, for example through the application of technologies that keep methane emissions low and capture rates high, then blue hydrogen can have a favorable environmental impact and offer an attractive bridging technology."'Serious threat' of fugitive emissions with hydrogen plan
More information: Christian Bauer et al, On the climate impacts of blue hydrogen production, Sustainable Energy & Fuels (2021). DOI: 10.1039/D1SE01508G
Provided by University of Aberdeen
Is hydrogen fuel really the clean energy climate change targets need?
Newly published research shows that blue H2 produces “substantial” emissions even with carbon capture.
Since COP26, hydrogen news headline s have been hot topics, but according to recently published research, the form most countries are leaning on as their clean energy future actually produces “substantial” emissions.
Blue H2 uses fossil fuels (other than coal) to power its production, followed by CCS.
Despite the positive attention blue hydrogen fuel has been getting from countries that are releasing their H2 strategies, new research shows that it may not be nearly as clean as all the hype suggests. This form of H2 is produced by processes powered by fossil fuels, most commonly natural gas. If the process stopped there, it would be called gray H2. What makes it blue is the carbon capture and storage (CCS) that is meant to keep the greenhouse gas emissions out of the atmosphere.
Blue H2 has been a major focus in the clean energy strategies of countries and regions around the world such as the United States, Canada, the European Union, Australia, and Japan, among others. However, a paper published in the Applied Energy journal suggests that the CCS technology isn’t as good as most of those countries had hoped. The research determined that “substantial” greenhouse gas emissions occur even when efforts are made to capture the carbon dioxide and store it underground before it can be released into the atmosphere.
Blue hydrogen fuel may not offer nearly the emissions reduction offered by green H2.
“Hydrogen made from natural gas leads to more fugitive emissions — methane that is leaked into the environment during the extraction and processing of natural gas — compared to just burning natural gas directly,” said the peer-reviewed paper’s co-author Fiona Beck of the Australian National University. “Including [carbon capture and storage] in the process actually increases fugitive emissions further, as more natural gas is needed to fuel the process.”
Over 100 countries, including the United States committed to a Global Methane Pledge at COP26, the UN climate summit in Glasgow, Scotland, which took place earlier this month. The commitment was to slash methane emissions by 30 percent by 2030 when compared to levels recorded in 2020. Methane is an exceptionally potent greenhouse gas, making it an important focus in efforts to reduce the impact of emissions on climate change. For many countries, reaching that goal relies on the use of hydrogen fuel instead of fossil fuels.
Hydrogen fuel made with natural gas may still be highly polluting even with carbon capture and storage.
Though green hydrogen fuel, produced using renewable energy such as wind and solar power, is considered cleaner, it comes with substantial hurdles in its way. This process of splitting water comes with a higher price tag and often requires new electricity generation to be constructed from the ground up instead of using fossil fuel-based power already in place. As a result, it is typically associated with considerably higher prices.
The research examining the emissions from blue H2 follows one published in August by Cornell and Stanford University. They found that blue H2 pollutes 20 percent more greenhouse gas than burning gas or coal for heat. In the new study, researchers from Australian National University compared both the financial cost and the emissions resulting from producing hydrogen fuel using fossil fuels with those made with renewable energy.
Recent studies have been looking into the various technologies employed, commonly assuming that high carbon capture rates are in place. That said, those studies have not assessed the impact of fugitive emissions and lower capture rates on the total emissions released and the costs associated with production, said the researchers.
Green hydrogen fuel may be cheaper than blue within the Australian market.
While producing green hydrogen fuel is associated with higher costs because renewable energy sources such as solar and wind are not yet locally established, that could change, said the researchers. They pointed out that if they invest heavily in clean energy, such as solar that would take advantage of the abundant sunshine in Australia, as well as its powerful winds and vast amounts of land available, the cost of clean H2 could rapidly fall once those power sources are in place.
“Our work highlights that large investment in fossil-fuel-based hydrogen with CCS could be risky, locking in a new fossil fuel industry with significant emissions, and one that is likely to be out-competed by renewable technologies in the future,” said Beck.
About Australian National University
The Australian National University is a public research university that boasts seven teaching and research colleges on top of a number of national institutes and academies.
No comments:
Post a Comment