A trilemma is a situation that presents three possible choices to a complex challenge. Due to mutual exclusivity of the available choices, achieving them simultaneously is always a daunting task. The overarching objective is to achieve the three possible solutions in a balanced manner.
Energy trilemma refers to the need to find a balance between reliability, affordability, and sustainability for a given country, utility, or power pool as illustrated in Figure 1. Very reliable energy is not of much use if it is very expensive. On the other hand, affordable energy is not good for an economy if it is rarely available or is generated and transmitted in ways that destroy the environment.