In this study, different momentum models for vertical axis wind turbines (VAWTs) are investigated and compared for different operating parameters. The performance over different rotor solidities and aspect ratios is studied to find the best configuration of the turbine. By comparing different models, the merit of double multiple streamtube model is established. Three different airfoils were investigated using the parameters of reference turbines from the literature. NACA0015 is found to be advantageous among NACA0012 and NACA0021. Also, the effect of different number of blades is studied and it is found that two-bladed rotor with NACA0015 airfoil provides excellent performance. By studying the turbine aspect ratio, it is found that a VAWT of 5.1 m height and 4.25 m diameter will generate a maximum power coefficient of 36.13% at TSR of 5.51 with good starting behavior.