Assessment of hydrogen embrittlement in pipelines due to hydrogen/natural gas blending

In alignment with Canada's 2050 net-zero emissions, natural gas utilities companies are exploring ways to provide cleaner energy. For example, Enbridge is undertaking a $5.2M project to pilot the blending of 2% renewable hydrogen with natural gas in their natural gas distribution network. When burned, hydrogen does not emit carbon dioxide, hence, cleaner energy. This low carbon hydrogen-blending project is the first of its kind in North America and is an important step in greening the gas supply. However, higher hydrogen content needs to be blended with natural gas for a significant reduction in greenhouse gas emissions. Implementation of hydrogen blends into the natural gas network for homes and industrial applications can impact existing and new pipeline networks. Hydrogen can induce an environmentally assisted failure of steel gas pipelines that results mostly due to the combined action of hydrogen and residual and applied stress. This phenomenon is known as hydrogen embrittlement and may lead to catastrophic failures. The objective of this project is to assess the effect of blending hydrogen with natural gas on pipe steels and determine the maximum blending limits in new and existing gas distribution networks for the safe operation of gas pipelines. The proposed project is in collaboration with the National Research Council of Canada and Enbridge Gas Inc. Hydrogen is a versatile and unique energy carrier that enables economic and environmental benefits and can play a significant role in cleaning of energy systems. Furthermore, the installation, operation, and maintenance of the natural gas/hydrogen blend distribution pipeline networks across Canada is expected to generate thousands of new skilled workers and engineering jobs. Hence, sets the path to economic recovery post pandemic.