This work introduces a comparison between the conventional single-rotor wind turbine, and a twin-rotor wind turbine. Multi-Rotor wind turbine concept solves many drawbacks of the single-rotor, including ease of transport, installation, and maintenance, in addition to reduced mass of the whole turbine. In this work, the NREL 5MW wind turbine has been scaled down to a single rotor configuration of 40 cm diameter, and a twin-rotor configuration with two 20 cm diameter rotors, such that both configurations have the same span. Blade Element Momentum (BEM) theory has been used for simulations to calculate aerodynamic loads and produced power. The BEM algorithm was verified by performing a simulation on the original NREL 5MW rotor and compared to the definition report of the turbine. Simulations on the scaled-down single and twin rotor configurations have shown that although the produced power by the twin-rotor is 50% of that of the single-rotor, but the thrust load is 50%, rotor torque is 20%, and overall mass is 25% of the single-rotor configuration. The reduced inertial and aerodynamic load indicate lower cost of energy, and hence the twin-rotor is superior to the single-rotor of the same span size.