This paper Techno-economic design of a standalone solar PV system with case study, TY Danjuma conference building, Rivers State University (RSU) Port-Harcourt provides alternative electric power services to the building. The area or building under consideration uses the off-grid power generation model having identified the inadequacy and irregular power supply which causes man-hour loss during the working period. There is enough solar energy to generate emission-free power. In literature, it has been seen that researchers are advocating for the utilization of these abundant natural resources to generate power. The long-run operational benefits cannot be neglected. To achieve the aim and objectives of this research, an analytical (components-wise) method was adopted. The various components required to provide green energy services were thoroughly and chronologically computed. The analysis provides specifications for the components as mentioned in the materials section and concerning the load demanded. Without a thorough load audit, the required solar PV and its delivery gadgetry would not be adequate. Hence, load survey, assumption and design calculations, etc., to achieve the 42kWp with 140 numbers of panels; 48 numbers of 200Ah, 12V deep cycle batteries, 25kVA inverter (or with two sets of inverters, 15kVA and 10kVA, 48Vdc/220Vac), 6 numbers of 150Amp, 48V solar charge controllers or a single 900Amp,48V solar charge controller was evaluated. The specification evaluated and presented was based on the load computed and the prevailing market for available components. From the techno-economic viewpoint of using solar-powered systems or diesel-powered generators, it was obvious that the solar-powered system has many more advantages in terms of daily, monthly or yearly running and maintenance costs as comparable to diesel-generator systems. Thus, it will be interesting to note that adequate utilization of renewable energy for electricity generation will be the best practice in the socioeconomic development of a state or a nation.