Hydrogen is a necessary element in the transition to
sustainable
energy systems and plays a crucial role in achieving net zero emission
targets. However, the current methods of hydrogen production are characterized
by high carbon emission intensities. For instance, the production
of hydrogen is responsible for approximately 1.05 billion tons of
CO2 annually. This equates to about 11 kg of CO2 emitted per kg of hydrogen produced, significantly higher than many
other industrial processes like ammonia, iron and steel, methanol,
ethylene, and cement production. To address the urgent need to meet
global decarbonization goals, it is crucial to develop and scale up
low-carbon hydrogen production technologies, especially given the
significant carbon emissions currently associated with existing methods.
This review investigates to strategies for decarbonizing the steam
methane reforming (SMR) process, exploring multiple pathways to significantly
reduce its carbon footprint. These approaches include SMR with carbon
capture and storage, SMR with electrolyzer, standalone electrolyzer,
electrification of SMR (e-SMR), and improving energy efficiency within
existing SMR infrastructures. Additionally, alternative methods such
as dry methane reforming and methane pyrolysis are emerging techniques
that utilize natural gas to produce low-carbon hydrogen, offering
reductions in carbon emissions compared to traditional SMR. This study
presents a comprehensive analysis of low-carbon hydrogen production,
offering valuable insights into the pathways for achieving this goal.
It identifies the key opportunities and challenges in commercializing
these technologies and provides strategic recommendations to enhance
their feasibility and market adoption, which are enhanced by ongoing
research and development efforts. Achieving low-carbon hydrogen production
can be realized through the integration of carbon capture and utilization
and the use of low- or high-temperature electrolyzers, which significantly
reduce the overall carbon footprint per unit of hydrogen in the short
term. In the medium to long term, low-carbon hydrogen can be produced
effectively via water electrolysis or e-SMR. The strategic integration
of these technologies offers a sustainable pathway for hydrogen production,
aligning with environmental and economic goals.
