Scenarios for different 'Future Indias': sharpening energy and climate modelling tools

India is crucial to the future of the global energy system, and hence to efforts to mitigate climate change. However, projecting India's energy future is challenging because of a number of structural uncertainties related to its still emergent development process - there are multiple 'future Indias'. This is particularly so given India's unusual historical development pattern and economic structure. This paper reviews more than 40 energy system scenarios for India to 2050 including scenarios of different policy stringency. This analysis suggests that the task of drawing policy insights is hampered by widely divergent, often non-transparent and insufficiently discussed, assumptions about GDP and its structural attributes as implied by sectoral energy consumption, industrial intensity of GDP, and sectoral demand patterns. It is these assumptions that crucially drive the divergence in scenario results, even more than assumptions about energy and climate policy per se. While divergent results are important for exploring the range of possible future pathways, policy insights can only be generated if scenario producers adequately convey a sense of causality, probability and desirability underpinning their scenarios. This requires linking more detailed socio-economic scenario storylines with the input assumptions and output results of energy system scenarios. To improve modelling for policy insight, the paper proposes that more attention be devoted to developing overarching socio-economic development scenarios, linking these to sector dynamics, and unpacking and interpreting model results. Key policy insights India's development pathway is characterized by a relatively low level of industrialization, precocious growth of services, and low and slow urbanization compared to similar countries. The unusual features of India's development pathway have a material impact on its energy system. There is a wide range of uncertainty pertaining both to India's future rate of GDP growth, but also to the persistence or reversal of the aforementioned structural characteristics. Existing modelling studies do not adequately detail and contextualize assumptions about India's macro-scale development pathway, and its links to micro-scale patterns of sectoral energy demand and supply, leading to a wide divergence of results and uncertainty over how to interpret them. Addressing these lacunae requires enhanced transparency and discussion of overarching socio-economic development scenarios for development, linking these to sector dynamics, and unpacking and interpreting model results.