IN AN EFFORT TO REACH NET-ZERO emissions by 2050, Canada has focused its attention towards the emerging industry of green hydrogen power as a source of renewable energy. The production of hydrogen is completed through elec- trolysis, whereby electrical energy is applied to split water into oxygen and hydrogen. This process of electrolysis is considered "green" when renewable sources, such as solar and wind power, are used to generate the required electricity.

Having one of the largest freshwater reserves in the world, Can- ada has an opportunity to use green hydrogen power on an indus- trial scale. However, regulatory policies and safeguards should be observed and considered in conjunction with the growing use of hydrogen. In Ontario, certain regulatory safeguards are found under the Ontario Water Resources Act and Ontario Regulation 387/04. For example, Ontario requires individuals to obtain a permit if 50,000 litres or more of water per day is captured from the environment, unless certain exemptions are met. In addition to the regulatory framework, attempting to utilize desalination processes to convert saltwater into freshwater or converting reused wastewater into electrolysis feedstock should be considered when attempting to industrialize hydrogen power. Overall, maintaining legal safeguards is critical in order to ensure the conservation, protection and wise use and management of the waters of each province.

To properly harness hydrogen for industrial use, Canada will require additional investment into its infrastructure. For example, steel transmission pipelines and steel storage vessels are currently used for most methods of gas transportation and storage. How- ever, steel is susceptible to hydrogen embrittlement, whereby the introduction of hydrogen may cause the steel to crack and begin to leak. Although hydrogen escaping from leaking pipelines or storage vessels may not cause direct damage to water sources, con- cern should be raised if other natural gases containing pollutants are transported using the same equipment. New transportation and storage methods being proposed include converting hydrogen to liquid ammonia, which is not corrosive to steel. However, as ammonia is toxic to humans and aquatic organisms, further risk is introduced if ammonia spills occur within the water sources. With this concern in mind, Canada must consider constructing new pipelines and storage vessels with specific coatings or complete substantial modifications to its existing infrastructure in order to prevent future complications.

As green hydrogen power uses progress, continuing to maintain adequate protection of Canada's water sources will be imperative in order to allow for the sustainable utilization of water to power tomorrow's future.

Using hydrogen on an industrial scale will also require consideration of the potential dangers flowing from increased NOx emissions. Although green hydrogen is produced without generating polluting emissions, hydrogen combustion produces NOx emissions in greater quantities than current methane combustion. As a result of increased NOx emissions, poten- tial impacts include the degradation of water quality and the surrounding environment as NOx emissions may contribute to nutrient pollution and acid rain. Although current regulations under the Multi-Sector Air Pollutants Regulations establish limits of allowable NOx emissions in Canada, further evaluation of these regulations will be required if hydrogen power is utilized on an industrial scale. While minimizing NOx production is possible through controlled combustion of after-treatment applications, this may result in reduced power output and increased costs and complexity. With these concerns in mind, hydrogen combustion applications will require further optimi- zation and development to minimize environmental and public health concerns and to derive the greatest benefits from growth in hydrogen use.

While the industrial use of hydrogen poses risks, it may also benefit current infrastructure within Canada. For example, Ontario utilizes a combination of run-of-the-river (ROR) and dam-based (DB) hydroelectric generation plants to produce electricity. However, limitations of ROR plants are that they are considered an "unfirm" source of power, meaning they have limited energy storage capacities. Accounting for this limitation, power produced from ROR plants could be used to provide the electricity required for electrolysis, thereby incen- tivizing further integration, development, and use of ROR and hydrogen production plants. However, as previously discussed, developing safe hydrogen transportation and storage infrastruc- ture around hydropower projects will be necessary in order to ensure that the water sources being utilized remain properly protected.

Overall, the adoption of green hydrogen power as clean renewable energy is still in its infancy, with various significant challenges ahead. Although the transition into green hydrogen power may provide Canada with an alternative to fossil fu- els, innovation will be required to build and strengthen green hydrogen infrastructure for industrial use. As green hydrogen power uses progress, continuing to maintain adequate protection of Canada's water sources will be imperative to allow for the sustainable utilization of water to power tomorrow's future.

Originally published by Water Canada, May/June 2023.

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