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Hydrogen production from waste holds promising prospects. Hydrogen generation coupled with power generation involves the direct pyrolysis and gasification of waste during its treatment to obtain hydrogen. Currently, the average moisture content of domestic waste in our country is 50%-60%, which not only increases the costs associated with flue gas treatment for enterprises but also reduces power generation. In the process of hydrogen production via waste gasification, the moisture content of the raw waste does not affect the gasification of the material; on the contrary, it can help increase the proportion of useful gases in the syngas. Furthermore, once economies of scale are achieved, the cost of hydrogen production via waste pyrolysis and gasification is expected to drop below 20 yuan per kilogram, which is comparable to the costs associated with hydrogen production technologies using fossil fuels such as natural gas. On September 14, Dongfang Electric Group Dongfang Boiler Co., Ltd. (hereinafter referred to as “Dongfang Boiler”) signed a letter of intent for cooperation on a demonstration project for waste-to-energy generation combined with hydrogen production in Tongnan District, Chongqing. Eastern Boiler told reporters that the coupled waste-to-energy and hydrogen production process does not involve electrolyzing water to produce hydrogen. Instead, hydrogen is obtained through the pyrolysis and gasification of waste directly. This approach not only enhances the economic and environmental benefits of waste treatment, but also provides a low-carbon and clean source of hydrogen for the hydrogen energy industry. New ways to turn waste into treasure: Currently, the main methods for dealing with waste are landfilling or incineration for power generation. In China, the primary technologies used for incinerating municipal solid waste are grate furnaces and circulating fluidized bed furnaces. These types of equipment require large investments and have high operating costs, and they are mainly used for the treatment of municipal solid waste on a large scale. A staff member from Dongfang Electric, responsible for the waste-to-energy with hydrogen production and hydrogen energy demonstration projects, explained that the compounds generated during grate furnace combustion and circulating fluidized bed combustion, along with fly ash, can easily cause secondary pollution to the environment. It is becoming increasingly difficult to locate sites for such projects, and it is particularly crucial to find ways to process waste in a low-carbon manner. Against this background, pyrolysis gasification technology, as a new type of waste management technique for household waste, is gradually gaining attention. The aforementioned experts stated that the pyrolysis and gasification of waste possess excellent environmental benefits; it enables a significant reduction in the amount of compounds formed as well as in the emissions of fly ash. Organic materials are broken down into simple gas molecules such as carbon monoxide and hydrogen, which can be used as fuels or raw materials in the chemical industry. This approach facilitates the harmless treatment, reduction, and recycling of household waste. According to reports, the average moisture content of untreated municipal solid waste in China currently stands at 50%-60%. This excessively high moisture level not only increases the costs associated with subsequent flue gas treatment for waste incineration facilities, but also reduces the amount of electricity that can be generated from the waste. In the process of hydrogen production via waste gasification, the water content of the raw waste does not affect the gasification of the material; rather, it can help increase the proportion of useful gases in the syngas. Furthermore, municipal solid waste contains large amounts of hydrocarbons, making it a better raw material source for hydrogen production via gasification compared to fossil fuels such as coal. He pointed out that many places in the country have now specified the use of pyrolysis gasification technology when selecting waste disposal methods. Against the backdrop of carbon peak and carbon neutrality, and with the development of hydrogen energy industry in China, there will be a growing demand for low-carbon and clean hydrogen for large-scale use. Accordingly, the application scenarios for producing hydrogen from waste are becoming increasingly clear, offering significant economic and environmental benefits. What are the economic benefits of producing hydrogen from waste? The aforementioned individuals did some calculations for the journalists: the economic evaluation of hydrogen production from waste involves the cost of hydrogen production, equipment depreciation, taxes, labor costs, various fees, and a reasonable profit margin. Under reasonable prices for raw materials and electricity costs, the current production cost per kilogram of hydrogen is around 10 yuan/kg for hydrogen produced from coal; around 17 yuan/kg for hydrogen produced from natural gas, naphtha, heavy oil, or methanol; 21 yuan/kg for hydrogen recovered and purified from industrial by-products; and around 30 yuan/kg for hydrogen produced through water electrolysis. “Excluding subsidies for waste treatment, the production cost of hydrogen in the syngas purification and high-purity hydrogen production sections is 14.94 yuan per kilogram, while in the waste gas processing section, the cost of producing pure hydrogen is 13.80 yuan per kilogram. Therefore, the total production cost of high-purity hydrogen from household waste is approximately 28.74 yuan per kilogram. The cost of producing hydrogen from waste will decrease further when calculating the subsidies for waste disposal. Once scale effects are achieved, the cost of producing hydrogen through waste pyrolysis and gasification is expected to drop below 20 yuan per kilogram, making it comparable to the cost of hydrogen production using fossil fuels such as natural gas. It can be seen that the technology of producing hydrogen through the pyrolysis and gasification of household waste holds great potential for application. ”The aforementioned person said. Furthermore, compared to hydrogen production from fossil fuels, hydrogen production from household waste results in lower carbon emissions, offering significant environmental benefits. The aforementioned individual said, “By using waste to produce hydrogen, carbon dioxide emissions can be reduced by about 23–31 tons per ton of hydrogen produced.” The development of hydrogen production from waste is expected to open up a new pathway for waste treatment technologies, and it will also become a key core technology for the comprehensive environmental management of landfill areas. ” It effectively boosts corporate profits. In July 2019, the Ministry of Finance stated that, on one hand, it planned to continue the existing subsidy policies for existing projects ； On the other hand, given the low efficiency of waste incineration power generation projects and their poor ecological benefits, the proportion of new projects eligible for subsidies will be gradually reduced, in order to encourage support for this industry through market-based mechanisms such as waste disposal fees. It is understood that the main sources of revenue for waste incineration companies in our country come from two aspects: one is the waste disposal fee, which means a fee has to be paid for each ton of waste processed, with the average price in this industry ranging from 50 to 80 yuan. The second source of income is the electricity sales revenue. Data shows that in 2018, waste incineration power generation plants generated an average of 283 kilowatt-hours of electricity per ton of waste, at a uniform benchmark electricity price of 0.65 yuan per kilowatt-hour. This means that, aside from subsidies, the revenue generated from the disposal of one ton of waste is less than 200 yuan. Faced with the gradual reduction of subsidies, waste-to-energy companies urgently need to improve the efficiency of waste treatment in order to overcome their survival challenges. “Currently, under normal circumstances, the price of high-purity hydrogen gas for fuel cells is between 55 and 60 yuan per kilogram. Therefore, compared to waste incineration, using pyrolysis-gasification technology to process municipal solid waste not only enables large-scale reduction of such waste but also generates hydrogen gas of high value suitable for fuel cells during the waste treatment process, thereby effectively increasing the profits of waste-to-energy companies. ”The aforementioned person said. It is worth noting that in countries such as Germany, Japan, and the United States, the application of pyrolysis-gasification technology for municipal waste has evolved from medium-temperature gasification to high-temperature gasification, which offers better environmental benefits. In China, however, this technology is not yet mature, and its industrial application is still in its initial stages; continued attention is needed.