AN INTEGRATED ASSESSMENT OF THE FUTURE “HYDROGEN ECONOMY”: DECARBONIZATION POTENTIAL, SOCIETAL IMPLICATIONS, AND POLICY APPROACHES

Abstract

Recently clean hydrogen has captured the attention of policy communities, as evidenced by the publication of hydrogen “roadmaps” or “strategies” by dozens of nations. This is partly because it can be produced from numerous primary energy resources and utilized in a plethora of ways to enable decarbonization. However, there remain open questions as to how the energy carrier should contribute toward carbon dioxide (CO2) mitigation. Additionally, less is known about its impacts on other societal objectives and whether government plans for hydrogen are driven by realistic expectations regarding its ability to facilitate emissions reductions. This dissertation involves three studies which simulate energy transitions within the Global Change Analysis Model (GCAM), each aiming to help illuminate hydrogen’s potential impact on society. First, clean hydrogen supply and demand within the context of decarbonization is investigated. In this research, it is found that hydrogen could be a decentralized energy carrier, as a large portion of its production is enabled by onsite production (i.e., at the location of the end user). In terms of demand, although it will represent a smaller portion of global final energy compared to alternatives, hydrogen enables CO2 mitigation in difficult-to-electrify end uses (e.g., satiating demand for industrial high-temperature heat). The second topic of this dissertation examines hydrogen’s potential implications for the water-energy-food nexus. It is found that clean hydrogen production is unlikely to be a large source of water demand, however, its availability in the forthcoming energy transition could cause larger indirect changes in water demand for many regions of the world. Additionally, clean hydrogen availability is found to enable lower staple crop prices, as it provides a method of reducing CO2 associated with fertilizer manufacturing. Lastly, this dissertation analyzed the Japanese and Korean national hydrogen plans. Aligning with the results from the first research topic of this work, hydrogen’s use within their economies is lower than alternative decarbonization strategies (e.g., direct electrification). As a result, the national plans of both nations are found to be overestimating the scale of hydrogen supply. Further, both countries are generally setting numerical goals for hydrogen deployment in areas of the economy that are less economically efficient compared to alternative sectors where it could both facilitate decarbonization as well as bolster their economies.