The Role of Hydrogen Value Chains in Decarbonised Energy Systems

: (Alternative format thesis)

Abstract

Decarbonisation presents numerous challenges to energy systems. For example, renewable electricity sources such as wind and solar can provide low-carbon energy, but are variable, so new methods must be found to balance energy demand and supply. Furthermore, heating, transport and industry also require decarbonisation.
As a low-carbon and relatively energy-dense energy carrier, hydrogen could be used to aid energy decarbonisation, by providing electricity storage, as a transport fuel, heating buildings, or as a chemical feedstock. However, with multiple production pathways and applications, it is unclear how hydrogen should be implemented to provide the best support to decarbonisation. Modelling of energy systems can help to assess this.
In this thesis, a review of power-to-gas projects identifies the growing interest in hydrogen globally, and identifies key requirements for modelling hydrogen in energy systems. Hydrogen can provide energy flexibility in several different energy sectors, or even enable coupling between them. Therefore, hydrogen must be modelled with sufficient spatial, temporal and technological detail so that these synergies can be identified. This thesis argues that many influential global energy scenarios lack these details, which may explain the mixed coverage of hydrogen in the scenario results.
Value chain optimisation is used to explore how hydrogen can assist in energy decarbonisation. A value chain model of a national energy system is presented, and configured in the thesis in order to represent hydrogen and associated technologies within evolving energy systems. From data gathered from existing energy systems and emerging technologies, a series of scenarios are designed that explore the role of hydrogen in the supply, management and demand of energy.
The scenario results show that hydrogen could be valuable for providing flexibility to energy systems, for example balancing supplies and demands of electricity and moving energy between sectors and regions. However, bulk hydrogen production is relatively expensive, due to the costs of the energy feedstock, and losses in the conversion to hydrogen. Therefore the flexibility benefits of hydrogen may not be sufficient for it to be competitive in current markets. With policy support, for example in industry or for partial injection into gas grids, hydrogen supply chains could become established, and then hydrogen can begin to provide wider energy system benefits.

Date of Award	20 Jan 2021
Original language	English
Awarding Institution	University of Bath
Supervisor	Sheila Samsatli (Supervisor), Semali Perera (Supervisor), Ian Llewellyn (Supervisor) & Jose Bermudez (Supervisor)