Sensitivity analysis of feed-in tariff in joint generation and transmission expansion planning considering the inertia requirement of the grid

The need for a cleaner environment with lesser fossil fuel-fired generators has increased the call for higher share of renewable energy generators (REGs) in the grid. To achieve this, various economic incentive schemes have now been introduced by the government to speed up investment in renewable energy technologies. However, it is important to also consider the stability of the grid even as more REGs are being integrated. To this end, this paper proposes a novel feed-in tariff (FiT) and inertia integrated generation and transmission expansion planning (GTEP) optimization model, which maximizes the FiT incentive scheme and the overall system inertia, while minimizing cost and CO 2 emissions. The proposed model is then implemented on an IEEE 6-bus system and solved using CPLEX solver in GAMS under three study cases. The model simulation result obtained reveals that the introduction of FiT into the GTEP model reduces the overall system cost by 11.9% (599 M$ to 526 M$), while the integration of system inertia into the GTEP model increases the overall system inertia by 8% (5.680 s to 6.139 s). In addition, sensitivity analysis results reveal that as the penetration of REGs into the grid increases, the total system cost, and FiT received also increase, however, the fraction of FiT payment received relative to the total investment cost decreases after 50% REGs penetration level for the same FiT rate. Finally, comparing the model results with other soft computing optimization techniques showed its superiority in terms of speedy convergence and computation time.