Objective: The electricity-to-hydrogen technology can convert surplus renewable energy electric energy into chemical energy. Hydrogen plays an important role in transportation, power generation, and other fields. Therefore, developing electrochemical (P2X) technology for renewable energy consumption effectively solves renewable energy curtailment.
Methods: The four aspects of market scale, technical route, energy conversion efficiency, and demonstration project progress are reviewed, and the energy efficiency of the four electrochemical technologies is compared, Power consumption, marginal electricity price, equivalent output, and market share five major technical and economic indicators. To analyze the strengths, weaknesses, opportunities, and threats of P2X in China, a literature review survey was conducted, relying on recent two-decade publications from four main publishers: Scopus, Springer, Wiley, and Taylor and Francis. Keywords were selected from the first-hand references based on their impact on P2X or related topics listed in the literature databases. The keywords as Power to X, Power to chemicals, PtX, and P2X were chosen according to their actual involvement or keen interest in P2X projects.
Results: The research results based on the low-temperature electrolysis technology route show that the comprehensive energy efficiency of the electricity-to-methane and electricity-to-gasoline technologies is higher (50%); the electricity-to-gasoline technology is the most economical (marginal electricity price is 0.37 yuan/kWh), but the synthesis process requires carbon monoxide and carbon emissions, And the technical risk is high; the promotion of electricity to ammonia will have the greatest impact on the market (17.18%). Reducing coal consumption by about 22.85 million tons and the environmental protection significance of electricity-to-ammonia conversion (reducing carbon emissions by about 39.1 million tons) are two important directions for future electrochemical technology.
Conclusion: Facing the development of P2X technology in the future, the plan and economics of the high-temperature electrical and chemical technology route based on high-temperature solid oxides were preliminary discussed and prospected.