(471f) Co-Optimized Power and H2 Infrastructure Planning for Multi-Sector Decarbonization

The past decade has seen significant progress in CO₂ emission reduction in the power sector, while progress in other sectors has remained sluggish. With cost reductions in fuel cell and electrolysis technologies and power sector decarbonization, Hydrogen (H₂) is becoming an increasingly appealing option for reducing emissions from other end-use sectors, like heavy-duty transport, heating and industry, where electrification may be challenging. Meeting spatially and temporally varying H₂ demand requires significant infrastructure investments in H₂ generation,storage and transport. To date, most studies on hydrogen infrastructure planning have focused on H₂ use in transportation and on evaluating the trade-offs within the H₂ supply chain, without consideration to the dynamics of its interactions with the electricity sector. The latter could include: a) H₂-based energy storage to manage wind, solar, and demand variability at multiple time-scales, b) flexible electrolytic H₂ production coordinated with electricity adequacy and c) transporting H₂ or derived carriers instead of electricity to balance spatial variations in energy supply and demand. Understanding the implications of these interactions on the overall cost competitiveness of H₂ use requires developing scalable decision-support frameworks with adequate representation of temporal and spatial variability in cross-sectoral interactions.

We have developed a framework for power and H₂ infrastructure planning that determines the least-cost mix of electricity and H₂ generation, storage, and transmission infrastructures to meet power and H₂ demands subject to a variety of operational and policy constraints. Notably, the model includes hourly representation of power and H₂ system operation, that is made computationally tractable using judicious approximations and offline time-domain reduction strategies. The developed optimization model can represent a wide range of power and H₂ technology options, including renewables, carbon capture and storage (CCS) applied to power and H₂ generation, and truck (gaseous and liquid) and pipelines for H₂ transportation.

We apply the model to study future electricity and H₂ infrastructure needs for the U.S. Northeast region under various carbon policy and H₂ demand scenarios. The study reveals several interesting insights. First, CCS is deployed for H₂ production via steam methane reforming at lower CO₂ prices (< $100/tonne-CO₂) than for power generation (~ $200/tonne-CO₂). Second, for scenarios with relatively small H₂ demand, the operational synergies between the power and H₂ sectors, especially at times when electricity prices are low or high, reduces the cost of power sector decarbonization compared to the case without H₂ demand. These findings indicate the importance for joint planning of electricity and hydrogen infrastructure for cost-effective energy system decarbonization.