In this research, a hybrid decision support system that combines the fuzzy risk scoring and Net Present Value (NPV) based methodology is presented for enhancing capital investment decisions under uncertainty. The conventional evaluation of investment on infrastructure is usually based on deterministic financial indicators and subjective opinion, which does not make sense for modeling the fuzziness and uncertainty associated with infrastructure. To overcome such a limitation, we used the fuzzy logic approach to analyze qualitative risk factors in order to convert the uncertain risk assessment by experts into quantitative risk scores. While the NPV approach is useful in quantifying a project’s worth in terms of the expected cash flow. The hybrid model balances the evaluation of financial performance and uncertainty–based risk by integrating these two frameworks. Simulation results show that the proposed model has significant superiority in predictive precision, considering higher R-WES, smaller RMSE and more robust under different investment situations than other usual models. The results suggest that this fuzzy–NPV integration can be practically useful for evidence-based decision-making, as a more robust and transparent approach to managing capital investment in real-world uncertain conditions, especially for the planning of power grid infrastructure.