In this paper we consider optimal timing (starting and ending) of the lockdown as an optimal stopping problem with entry and exit decisions as well as decisions relating to restriction on the social economic activities. The model involves a trade-off between economic activities and human health cares. Optimal threshold policies are shown when payoff functions are linear under specific assumptions. We also explore properties of the upper and lower threshold numerically with respect to parameters.

The main problems associated with the spread of renewable energy hinder further decarbonization, especially regarding the electricity supply-demand balance. The current practical solution for these problems is continuous investment in thermal power generation. In this study, we focus on investment decisions in new thermal power plants under uncertainty and capacity mechanism, and analyze the effectiveness of the mechanism and its future design, by applying the real options approach. We found that the capacity mechanism provides incentives for investment in a situation where renewable energy diffusion reduces thermal generation utilization and increases uncertainty in electricity prices.