Towards zero carbon hydrogen: Co-production of photovoltaic electrolysis and natural gas reforming with CCS

Although low emission hydrogen has the prospect of huge growth in the future, the cost challenge hinders the deployment and makes it weak in the global market share. Green hydrogen has the advantage of zero carbon emission and has achieved rapid development with the support of renewable energy. Limited by investment, electricity and technology, the large-scale application of green hydrogen faces challenges in the short term. Blue hydrogen comes from natural gas reforming, and its output is guaranteed. However, its production reaction requires high energy consumption and additional carbon emission treatment, resulting in insufficient sustainability. To solve the problem of high-efficiency and large-scale production of low emission hydrogen, a hydrogen co-production scheme combining photovoltaic electrolysis and natural gas reforming with CCS was proposed in this study. Electrolytic hydrogen production, natural gas autothermal reforming, CO₂ sequestration and saline purification in the cogeneration hydrogen production system are coupled by energy and materials such as electricity, O₂, CO₂ and water. The scheme is applied in Sichuan-Chongqing region to verify the feasibility and effectiveness. The results show that the proposed hydrogen co-production scheme can achieve cost reduction of up to 16.4%, and has long-term development prospects.