May 17, 2020

China's air pollution response threatens water

4 min
Man covers his mouth against smog
By Hua Wen, Tianyi Luo and Tien Shiao Record-setting levels of smog this weekshut down Harbin, a city of 11 million people in northeast China. Official...

By Hua Wen, Tianyi Luo and Tien Shiao

Record-setting levels of smog this week shut down Harbin, a city of 11 million people in northeast China. Officials blamed increased coal consumption during the first days of winter heating, underscoring the urgency of the China State Council’s recently announced initiative to address persistent smog in major cities.

But while the Air Pollution Control Action Plan has ambitious goals—cutting air particulates and coal consumption—it may create unintended problems for the country’s water supply.

The Plan aims to reduce particulate matter in the North China Plain by 25 percent and reduce coal’s share of the national energy mix to 65 percent by 2017. One of the plan’s key recommendations is to replace coal with cleaner natural gas, including synthetic natural gas (SNG) converted from coal. Converting coal to natural gas, however, is an extremely water-intensive process. One cubic meter of SNG requires 6 to 10 liters (1.58-2.6 gallons) of freshwater to produce. So in an attempt to control urban air pollution in the east, China might jeopardize its water supplies elsewhere.

Using WRI’s Aqueduct Water Risk Atlas, we overlaid the locations of these approved SNG plants on our water stress maps to assess the potential water risks. Many of these plants are located in water-stressed regions, and could exacerbate water scarcity. Read on for our major findings.

Chinese SNG Industry Faces High Water Risk

As of September 2013, the Chinese government approved 18 large-scale SNG plants with a total capacity of 75.1 billion cubic meters of natural gas per year (see full project list in appendix). SNG plants require water for cooling, production, and to remove contaminants post-production. China’s proposed SNG plants, most of them located in arid and semi-arid regions in Xinjiang and Inner Mongolia, together will consume a total of 500 to 700 million cubic meters of freshwater annually at full operating capacity. That’s almost 20 percent of the region’s total industrial water use in 2011. The plants would therefore significantly exacerbate stress in areas already experiencing chronic water shortages.

What Is Water Consumption?

When we refer to "consumption," we mean the portion of an area’s total water use that is not returned to the original water source. While coal production and synthetic natural gas facilities return most of the water they need to the source, a noticeable percentage of water is evaporated during the process of converting coal into natural gas—in other words, that evaporated water does not return to the source, and is therefore consumed.

Other findings include:

  • More than 76 percent of the proposed SNG capacity will face high or extremely high baseline water stress, meaning each of the locations either competes with many other users for limited available water supplies, or has very little water available at all.
  • 11 of the approved plants, eight from Xinjiang Province and three from Inner Mongolia, are located in catchments that do not have major reservoirs. They also face medium-to-high or high risk from seasonal variability. So, in the dry season, those plants may have to reduce production capacity or experience temporary outages due to the lack of resilience in water supply.
  • Under a memorandum of understanding with the Inner Mongolia Government, Beijing will become the first Chinese city powered by SNG, receiving at least 4 billion cubic meters of the fuel annually. This production would consume more than 32 billion liters of freshwater, enough to meet one million Inner Mongolians’ domestic needs for an entire year.

SNG development around the city of Ordos illustrates how these water-intensive plants can disrupt regional water security. In the middle of the Mu Us Desert, Ordos’ booming coal-to-gas bases face severe competition for water between domestic and industrial users. Our analysis found that Ordos’ five approved SNG plants will need approximately 140 million cubic meters of freshwater annually, which is around 10 percent of Ordos’ total water supply, or 40 percent of the region’s industrial water use as of 2011. Once these SNG plants are completed, they could further disrupt water supplies for farmers, herders, and other industries.

SNG’s Other Environmental Implications

While SNG emits fewer particulates into the air than burning coal, it releases significantly more greenhouse gases than mainstream fossil fuels. Peer-reviewed studies in the journal Energy Policy estimate that life-cycle CO2 emissions are 36–108 percent higher than coal when coal-based SNG is used for cooking, heating, and power generation. Rapidly deploying SNG projects might, therefore, be a step backward for China’s low-carbon energy strategy.

Seeking Solutions

China’s government will need to think carefully about whether SNG’s air pollution benefits outweigh its water and climate change costs. Additionally, since water risks will likely disrupt SNG production and new plants would further strain already stressed water resources, the national government must engage with the nation’s water authorities—in this decision, and in future energy planning. The Ministry of Water Resources and Ministry of Environmental Protection are good places to start. Meanwhile, water authorities should consider tightening caps on industrial water withdrawal and water-pollutant discharge or introducing stricter local environmental standards in high water-risk areas.

But to ensure a sustainable future, it’s important for China to prioritize energy projects that face fewer environmental risks, especially from water and greenhouse gas emissions. Only then will China more successfully manage its conflict between economic growth and resource demands and find lasting energy security.

Source:  World Resources Institute

Photo credit: TonyV3112 /

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Apr 16, 2021

Hydrostor receives $4m funding for A-CAES facility in Canada

Dominic Ellis
2 min
The funding will be used to complete essential engineering and planning, and enable Hydrostor to take critical steps toward construction
The funding will be used to complete essential engineering and planning, and enable Hydrostor to take critical steps toward construction...

Hydrostor has received $4m funding to develop a 300-500MW Advanced Compressed Air Energy Storage (A-CAES) facility in Canada.

The funding will be used to complete essential engineering and planning, and enable Hydrostor to plan construction. 

The project will be modeled on Hydrostor’s commercially operating Goderich storage facility, providing up to 12 hours of energy storage.

The project has support from Natural Resources Canada’s Energy Innovation Program and Sustainable Development Technology Canada.

Hydrostor’s A-CAES system supports Canada’s green economic transition by designing, building, and operating emissions-free energy storage facilities, and employing people, suppliers, and technologies from the oil and gas sector.

The Honorable Seamus O’Regan, Jr. Minister of Natural Resources, said: “Investing in clean technology will lower emissions and increase our competitiveness. This is how we get to net zero by 2050.”

A-CAES has the potential to lower greenhouse gas emissions by enabling the transition to a cleaner and more flexible electricity grid. Specifically, the low-impact and cost-effective technology will reduce the use of fossil fuels and will provide reliable and bankable energy storage solutions for utilities and regulators, while integrating renewable energy for sustainable growth. 

Curtis VanWalleghem, Hydrostor’s Chief Executive Officer, said: “We are grateful for the federal government’s support of our long duration energy storage solution that is critical to enabling the clean energy transition. This made-in-Canada solution, with the support of NRCan and Sustainable Development Technology Canada, is ready to be widely deployed within Canada and globally to lower electricity rates and decarbonize the electricity sector."

The Rosamond A-CAES 500MW Project is under advanced development and targeting a 2024 launch. It is designed to turn California’s growing solar and wind resources into on-demand peak capacity while allowing for closure of fossil fuel generating stations.

Hydrostor closed US$37 million (C$49 million) in growth financing in September 2019. 

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