The rapidly evolving energy sector needs a feature-rich, publicly accessible and usable analytical framework to examine and understand the sector to inform policy, investments etc. Prayas (Energy Group) has built an open-source, generic, customisable, free-to-use demand-oriented energy systems modelling platform called Rumi with this motivation, and built the PIER (Perspectives on Indian Energy based on Rumi) energy model of India through the decade of the 2020s.

The PIER modelling exercise identifies some interesting trends and policy insights for the Indian energy sector. There is a need for urgent policy attention to increase usage of modern cooking fuels, particularly in some states and regions. Systemic improvements in energy efficiency can help do ‘more-with-less’ in the form of providing better energy services with lesser energy. Consumer behaviour is identified as a key lever, since small changes in behavioural choices can significantly impact the country’s energy demand and supply mix. Regarding electricity supply, the study suggests caution in future coal capacity addition beyond what is in the pipeline as it could lead to undesirable lock-ins if India achieves its renewables targets. The PIER exercise also suggests that it may be desirable to revisit the relative shares of solar and wind in its planned renewables portfolio. These insights, along with a detailed description of the model inputs and structure are described in the attached report.

In addition to the above insights, the report presents various other results that may be of interest, such as the share of space cooling in residential demand and peak demand, the electricity generation mix in future years and India’s import dependence for various energy sources.

Rumi can be downloaded and used from, and PIER can be downloaded and used from In addition, the set of key outputs from PIER are available for download as a spreadsheet from this page.

We hope that the energy modelling community finds Rumi and PIER useful and will enrich them further using their own assumptions, data and methodology.

Note: Included is a list of corrigenda in the original report. None of these corrections change any of the results or conclusions of the original report.