This paper dives into the complex world of economic analysis in the context of medium voltage optimal planning, examining the extensive consequences of various discount rates from a variety of countries and scenarios. With a particular emphasis on multi-period investment strategies, renewable resource remuneration, and the persistent presence of uncertainty, this study seeks to illuminate the interplay of these factors and their cumulative impact on decision-making processes. The research uses a thorough analytical approach that includes various discount rate scenarios to highlight the intricate trade-offs and ramifications for parties involved in medium voltage infrastructure development by studying significant indicators such as Net Present Value, Internal Rate of Return and Payback. This research provides practical insights critical for guiding informed policy formulations and strategic planning in the domain of energy infrastructure development. The model is applied to a 180-bus realistic network that is primarily reliant on renewable energy sources. The results indicate the discrepancy between highly and lesser developed countries, in the way they value their future investments. The high discount rates make it less appealing for investors to profit from long-term projects in lesser developed countries.