Real options approach to renewable energy investments in Mongolia
Neal Detert Koji Kotani
Many developing nations are in transition from non-renewable to renewable energy in electricity generation. This research analyzes this type of changing investment environment for renewable energy projects such as wind farms and solar-thermal plants with the application of real options theory. The main intent is to explore the potential and to provide further insights for such a transition in developing economies through studying the case of Mongolia under coal price uncertainty. To evaluate the comparative attractiveness of either continuing to use non-renewable (coal-based) infrastructure or switching to renewable energy, we formulate social revenue functions for the two environments under the assumptions that coal-based operations generate negative externalities and renewable energy is externality-free. Framing the problem as a type of real options, we arrive at the optimal trigger prices of coal for switching technologies. With this analytical framework, we further pose some possible scenarios with respect to electricity price as well as negative externality valuation, and characterize when renewable energy investments become attractive. In sharp contrast to conventional wisdom in real options theory, we identify some situations where option values for switching technologies become negative in some price domains, and welfare losses are incurred. Overall, the result raises the possible risks in developing nations that waiting to switch energy sources yields huge losses under input price uncertainty. To avoid such a case in Mongolia, the government should remove coal subsidies and increase electricity prices or switch to renewable energy earlier rather than holding the option to wait, especially when people are willing to pay more for the removal of negative externalities.