GHG emissions from power generation, industrial facilities, commercial and residential buildings, and transportation are major sources of emissions in many developing countries. In Central Asia, the use of combined heat and power plants provides another source of emissions and provide opportunity for low-cost gains in energy efficiency and GHG emissions reductions. Expanding energy efficiency (EE) is consistently found to be a least cost resource for countries, utilities, and consumers to manage increasing demand and reduced GHG emissions. EE measures can reduce a country’s need for expensive peak generation and work in tandem with RE to reduce emissions. By accessing EE as a source of operational flexibility in the power system, this can improve integration of RE into power systems as a whole.