This research determines the techno-economic feasibility of valorizing as biofertilizer the nitrogen (N) and the phosphorus (P) from a municipal wastewater effluent using the microalgae Scenedesmus sp., contributing to phosphorus recycling, resource optimization, and diminishing eutrophication by capturing 74% of N, 97% of P, and 41% of chemical oxygen demand in effluents. The inoculum was conditioned in 20 L photobioreactors by weekly harvesting and refilling at room temperature (25 °C day, 12 °C night) with a 12:12 photoperiod and 4 L/min atmospheric air bubbling. The improved operational conditions were obtained using a Box–Behnken experimental design, establishing that 70% wastewater concentration (vol./vol.), 4.5% nutrient addition, and 3 days’ harvesting time were the best conditions. The estimated biomass production was 176 tons/year, and this represents a maximum net present value of 1.5 MUSD for a 6.8 Ha plant, capturing 10% of municipal wastewater effluent, which serves 64000 inhabitants. The representative operational costs (OPEX) were 32% for utilities, 30% labor costs, and 25% for raw materials, and the required capital expenditures (CAPEX) were 11 MUSD and are related to photobioreactors (64%) and land (21%). The findings demonstrate the potential of microalgae-based systems as a feasible and profitable approach to wastewater valorization, while also highlighting the need for scale-up validation and integration with existing treatment infrastructures, where land requirements and photobioreactor installation will be relevant for financial feasibility.

Currently, developing new or more efficient ways of producing bioenergy has caused governments from around the world to formulate compromises. These compromises translate, on a national scale, into government policies and strategies that aim to decarbonize the energy matrix of each country. The first step for efficient development is the quantification and energy-potential characterization of the available biomass. Using this framework, this study establishes the energy potential of the residual biomass produced by agricultural, agro-industrial, and forestry processes in Colombia, with gasification being the selected transformation technology. For this purpose, data from primary and secondary sources were analyzed. Next, some biomasses were prioritized according to their availability and physicochemical properties. Then, the theoretical energy potential of the total biomass produced in these productive sectors was estimated by using its physicochemical properties. The technical biomass–energy potential of the country (204.8–235.3 PJ) was estimated by considering the current level of unused biomass and evaluating the logistics and conditioning requirements of the gasification process, while accounting for the peaks and off-peaks of production in the country. Thus, if all the biomasses were processed in a gasification plant (22.2–24.0% efficiency), as proposed in this study, then the installed capacity—if the plant-use factor was 85%—would range between 1696.7–2111.3 MW. The results of the present research were validated by representatives of unions, companies, and government entities.