Regionalized Life Cycle Inventory of Power Producing Technologies and Power Grids in India

Abstract

Indian electricity production mix, power plant technological level and local production conditions vary considerably on the state level across the 29 Indian states and 7 union territories. Hence, national-level Life Cycle Inventory of Indian power producing technologies and power systems as presented in ecoinvent v3.2 may not represent well this high variability. The aim of this study is to create a consistent regionalized model of Indian power systems in order to evaluate the necessity of such regionalized inventory. Data collection covers state-specific key parameters of domestic power production and distribution, and inter-exchanges among the regional grids and with other countries in 2012-2013. Such regionalization work faces some data availability challenges. Power plant parameter data (e.g. efficiency, fuel quality, exact technology used) are mostly unavailable on plant level: if at all, relevant data are available on a state level. Moreover, local emission data are also mostly unavailable except emissions of CO2. Emission values for other important emissions (NOx, SOx, CH4, CO, PM) are, therefore, calculated based on assumptions and literature information. The impact assessment results show high variations among the various power grids due to different grid mixes, key parameter values and electricity losses during transmission and transformation (T&T). As an example, power from the Eastern grid shows nearly four times higher Global Warming Potential (GWP 100a, in kg CO2-eq/kWh) scores (1.6) than the North-eastern grid (0.4) and also considerably higher than the Northern (1.1) and Southern grid (1.2). The Western grid also corresponds to relatively high GWP score (1.4). Moreover, relatively high T&T losses have been inventoried. For example, in the Eastern grid, GWP scores for high, medium, and low voltage grids are 1.7, 1.8, and 2.1, respectively, which corresponds to up to 17% technical losses along the chain from gross production. To compare, in ecoinvent v3.2, the GWP score for the national-average of Indian electricity supplied at high voltage is 1.3 which is off the both highest and lowest regional score. This confirms the need of regionalized inventories for countries with large mix and key parameter variations in order to achieve higher accuracy in life cycle studies.