Abstract: This study develops an integrated evaluation framework covering wind-resource matching,engineering feasibility,reliability,net electricity delivered to the grid,market electricity prices,and life-cycle cash flow for 6 MW,8 MW,and 10 MW turbines in low-to medium-wind-speed onshore projects.Low-wind-speed power curves,wake effects,availability,curtailment,and auxiliary-power losses are converted into net electricity delivered to the grid.Equipment,foundations,roads,lifting,operation and maintenance,and major-component risks are incorporated into discounted cash flow.Levelized cost of electricity,net present value,internal rate of return,and simple payback period are used to compare alternatives,while incremental net present value and break-even additional generation identify the economic boundary of turbine upscaling.Under the base case of 5.5 m/s annual mean wind speed,a 100 MW-class onshore wind farm,20 years of operation,a 6%discount rate,and an electricity price of 0.30 yuan/(kW·h),the 8 MW scheme delivers the best overall economics.The proposed criterion provides quantitative support for capacity-upgrade decisions.