Rambøll UK – Heat recovery from hydrogen production.
Globally, it is increasingly recognised by governments and industry that hydrogen has an important role to play in delivering carbon emission reduction ambitions and supporting the transition to Net Zero.
In the UK, hydrogen has been identified by national and devolved governments as a credible key
pathway for achieving Net Zero Targets. Indeed, the UK’s Hydrogen Strategy1
suggests that 250 – 460 TWh of hydrogen could be needed by 2050, making up 20 – 35% of the UK’s final energy consumption. The primary role of this hydrogen would be to replace (or extensively displace) natural gas in parts of the energy system, and / or to act as an energy storage medium.
In the context of this study, only low / zero carbon hydrogen is considered, and in the current
landscape, the associated hydrogen production processes comprise:
- Green hydrogen production (Electrolysis with renewable electricity); and,
- Blue hydrogen production (Steam hydrocarbon (methane) reformation coupled with carbon capture).
Such hydrogen production produces very substantial quantities of waste heat and, to date, very
little attention has been given to this significant by-product, and the opportunities it presents if
captured and utilised.
This study seeks to address this knowledge gap, and the scale thereof. Indeed, as the scale of hydrogen production infrastructure grows, the quantity of available waste heat will also grow.
This presents substantial opportunities, including the decarbonisation of both existing and new
district heating networks, with associated opportunities to:
- Increase energy efficiency and revenue to hydrogen producers; and,
- Increase the availability of low cost, low carbon waste heat for heat users and suppliers (e.g. district heat network operators).
In terms of increasing the availability of low cost, low carbon waste heat for heat users, it has been estimated that by 2050 the quantity of waste heat arising as byproduct of hydrogen production could be between 31 to 144 TWh2.
This is equivalent to:
- Up to 131% of the UK domestic space heating demand3; and,
- Up to 27% of the total UK heating demand4.
Further, the literature review indicated that recovering waste heat from some hydrogen production processes (particularly green hydrogen production) should not have any negative impact on process efficiency. Indeed, various literature sources suggest that the system efficiency of electrolyser plants can increase by 14 to 32% by recovering waste heat. Thanks for staying up to date with Hydrogen Central.
This directly contradicts the opinion that hydrogen production and heat networks are in competition with each other, and these observations suggest there are clear and potentially very significant synergies between the hydrogen and heat sectors.
HEAT RECOVERY FROM HYDROGEN PRODUCTION, December 15, 2021
