The role of storage technologies in energy transition pathways towards achieving a fully sustainable energy system for India

In this work, a 100% renewable energy (RE) transition pathway based on an hourly resolved model till 2050 is simulated for India, covering demand by the power, desalination and non-energetic industrial gas sectors. Energy storage technologies: batteries, pumped hydro storage (PHS), adiabatic compressed air energy storage, thermal energy storage and power-to-gas technology are used in the modelling to provide flexibility to the system and balance demand. The optimisation for each time period (transition is modeled in 5 year steps) is carried out on an assumed costs and technological status of all energy technologies involved. Results indicate that a 100% renewable based energy system is achievable in 2050 with the levelised cost of electricity falling from a current level of 58 (sic)/MWh(e) to 52 (sic)/MWh(e) in 2050 in the power scenario. With large scale intermittent renewable energy sources in the system, the demand for storage technologies increases from the current level to 2050. Batteries provide 2596 TWh, PHS provides 12 TWh and gas storage provides 197 TWh of electricity to the total electricity demand. Most of the storage demand will be based on batteries, which provide as much as 42% of the total electricity demand. The synchronised discharging of batteries in the night time and charging of power-to-gas in the early summer and summer months reduces curtailment on the following day, and thus is a part of a least cost solution. The combination of solar photovoltaics (PV) and battery storage evolves as the low-cost backbone of Indian energy supply, resulting in 3.2-4.3 TWp of installed PV capacities, depending on the applied scenario in 2050. During the monsoon period, complementarity of storage technologies and the transmission grid help to achieve uninterrupted power supply. The above results clearly prove that renewable energy options are the most competitive and a least-cost solution for achieving a net zero emission energy system. This is the first study of its kind in full hourly resolution for India. (c) 2017 Elsevier Ltd. All rights reserved.