Development of Green Hydrogen Technology
Green hydrogen energy technology is to use renewable energy to produce hydrogen, convert renewable energy into electrical energy through solar cells, fans, water pumps and other generator sets, and electrical energy is converted into hydrogen through water electrolysis hydrogen production equipment, and the hydrogen is stored or directly transported to hydrogen applications Terminals, as power or transportation fuels, chemical raw materials, etc. to meet the needs of various industries for hydrogen energy. In addition to the traditional hydrogen production from water electrolysis, some new hydrogen production technologies that are still in the laboratory research stage have also been derived in recent years, such as solar hydrogen production, biomass hydrogen production, and nuclear energy thermal utilization.
Water electrolysis hydrogen producting is the most mature green hydrogen production technology. Hydrogen and oxygen are generated by electrolysis, and no carbon-containing compounds are discharged during the hydrogen production process, which is in line with the concept of green and sustainable development. The obtained hydrogen is converted into electric energy and integrated into the power grid or directly supplied to the load, which improves the comprehensive utilization efficiency of the energy system, helps to solve the problem of new energy consumption, and ensures the safe and stable operation of the power system. Due to its relatively high cost, low efficiency, high energy consumption and other factors, the commercialization of water electrolysis hydrogen production technology is restricted due to its simple equipment, mature technology and no pollution.
According to the different types of electrolytes, typical water electrolysis hydrogen production technologies are mainly divided into the following categories: alkaline electrolysis(ALK Hydrogen production technology), proton exchange membrane electrolysis (PEM Hydrogen production technology), solid polymer anion exchange membrane electrolysis (SPAEM technology), solid oxide electrolyze cells (SOEC technology).
At present, the alkaline electrolysis water hydrogen production technology is the most mature, and the hydrogen production cost is relatively low. It has basically achieved industrial large-scale application, but the energy efficiency is low; the PEM hydrogen production technology has a wider operating power range and a shorter start-up time. It can realize high current density electrolysis, low power consumption, small volume, high purity of generated gas, easy to achieve high pressure, and can well adapt to the volatility of renewable energy.
Some studies have found that SOEC can work under dynamic power output without obvious attenuation. The cost reduction of alkaline water electrolysis hydrogen production and PEM hydrogen production technology is limited, and the later research will focus on the balance between cost, efficiency and flexibility. The solid oxide water electrolysis hydrogen production technology is the electrolytic water hydrogen production technology with the lowest energy consumption and the highest energy conversion efficiency.