The design and operation of cost-effective power systems and high penetration of renewable energy and energy storage require a modeling approach that simultaneously reflects the system's reality. Although power systems with high penetration of renewable energy and energy storage have been analyzed in the past, more systematic analysis are in need to determine the impact of generation units' techno-economic parameters on the model's accuracy. This study investigated the effects of the techno-economic and spatial-temporal parameters, which will be referred to as combined techno-economic parameters, via seven scenarios. The combined techno-economic effects were demonstrated on optimal generation mix, renewable curtailments, variability status of storage units, and energy cost. The omission of combined techno-economic parameters results in the renewable generation to be more visible and with less curtailment while significantly decreasing the share of energy storage and decreasing the energy cost by 1.53 USD/MWh. As a result, if power systems assessment dismissed the evolving techno-economic and spatial-temporal parameters, the precision of cost-benefit analysis can be compromised, thus affecting the decision-making in terms of directing projects, regulations, and policies within the power industry.