The paper presents some critical remarks on a commercial pre-feasibility study for various concepts of hydrogen generation from dewatered sewage sludge. Three commercial offers (two from the European and one from the U.S. market) have been analysed in terms of chemical reactions and energy balance of the process. The analysis was done for a typical municipal wastewater treatment plant sized Population Equivalent (PE) = 160,000. It has been shown that one of the offers (despite being provided by a representative of a major European process engineering company) is incorrect regarding both the possible production resulting from chemical reactions and from the point of view of energy balance. Another commercial offer is thermodynamically correct however it excludes the unavoidable and crucial energy demand for drying of the sludge before processing. Based on these observations corrected values of hydrogen yield and energy consumption have been determined and process efficiencies have been calculated. It has been found that Technology#1 represents an impossible application due to major inconsistencies in the energy balance. The obtained efficiency for Technology#2 and Technology #3 equals 31.4% and 41.2%, respectively. Since the market for sludge-to-hydrogen conversion technologies is not well developed, and the information provided from the market is not fully reliable, it is recommended to gradually build the final solution starting from hydrothermal carbonization of sewage sludge, which can be used as the first step towards hydrogen production, but is also useful as an independent solution.