Introduction. The wastewater treatment process generates two byproducts biogas and biosolid. Biosolid is sewage sludge which has a high moisture content and low organic material. Currently, the biosolid is utilized as fertilizer to sustainably improve and maintain productive soils and stimulate plant growth, however there are some studies that show high heavy metal and pathogens content that turn the use of biosolid into a hazard for other species and the humankind. Objective. This paper shows another way for using this residual byproduct; The paper shows a technical and economical assessment about two power generation technologies as Dual-fuel Engines [DE] and Gas Engines [GE], using the syngas obtained from biosolid gasification as fuel. Materials and methods. In this study the scale-up factor method and the correlation method were used by determination of generation plants and gasification process cost, respectively. The variables studied were: investment cost, Syngas cost, M&O cost and generated energy cost, and the economical assessment was made with the financial factors Net Present Value [NPV] and Internal Rate of Return [IRR] with a project lifetime of 15 years. result. The main result of this study drew that a generation over 545 kWe with GE technology brings a best profit-earning capacity for the project. conclusion. The total capital investment