Energy efficiency and conservation values in a variable renewable electricity system

To address climate change, most world energy systems must convert to carbon-free sources including variable sources such as solar and wind power. Currently there are few examples of such systems, and their economics are not well understood. In this study we consider how much energy efficiency and conservation are optimal in a system relying on variable renewable sources. Modeling a renewable electricity system for Mauritius, we demonstrate that marginal benefits of energy efficiency are greater than average costs of electricity, and that the value of energy conservation at specific times of limited electricity supply can be more than double the average cost of electricity production. This suggests important roles for energy efficiency and conservation in future renewable electricity systems.