Assessing the Impact of Natural Gas and Hydrogen Blending in Integrated Energy System Modeling

This paper assesses the impact of natural gas and hydrogen blending in integrated energy system modeling based on a novel blending transport problem (B-TP). In contrast to a standard transport problem which oversimplifies technical realities of pipeline gas flows in the context of blending, the B-TP (mixed-integer linear program) ensures compliance with the maximum hydrogen blending rate and that natural gas and hydrogen flow in the same direction in a pipeline. To assess the impact of the B-TP, we formulate an expansion planning optimization model of the integrated power, natural gas, and hydrogen sectors based on the objective of minimizing total system cost. Our case study shows that the gas flow formulation strongly influences investment decisions in the power and hydrogen sectors and that omitting the technical realities of blending can ultimately lead to suboptimal infrastructure planning (represented in the model as “regret’’ in the form of non-supplied hydrogen).