An environmental and economic assessment of solar photovoltaics and nuclear energy in Maharashtra, India

Abstract

Maharashtra, the second largest state in India in terms of population and area, is a fast-developing economy and meeting its electricity demand is crucial for its economic growth. Currently, power production is causing severe environmental and security issues mainly because of the reliance on coal plants in the state. In order to meet SDG 7 “affordable and clean energy” proposed by UN, a government think tank called NITI Aayog helps set polices and targets for sustainable development of electricity production in states of India. However, the stakeholders are hindered to address the problems of sustainability dimensions due to a significant knowledge gap causing discrepancies in power policies. There is a need for a comprehensive approach which involves life cycle thinking and integration of the sustainability dimensions. Hence, this study adopts an integrated approach of environmental and economic dimensions of power sector in Maharashtra for suggesting NITI Aayog on policies and framework which can be used in the expansion of electricity generation capacity.
The framework followed in this study consisted of the four steps, indicator selection, environmental performance evaluation, economic performance evaluation, integration and policy implications. For this work, solar PV and nuclear technologies were selected and then the dimensions of technologies were integrated with respect to the predominant technology, coal.
Firstly, in order select indicators which relevant to SDG 7 and our case study, a literature study was conducted based on several criteria. After the analysis on the studies selected, GWP and LCOE indicators for environmental and economic dimensions were selected.
Furthermore, for evaluating the environmental performance of the technologies, LCA studies were used to quantify GHG emissions and to identify hotspots in life cycle stages. A methodology was followed to harmonise the published results of the selected studies to reflect the current status of Maharashtra conditions. The GHG emissions of solar PV was found to be 39 g CO2 eq/kWh of which 89% was contributed from manufacturing phase of the modules whereas GHG emissions of nuclear energy was estimated to be 12.5 CO2 eq/kWh in which 75% of the emissions is during HW production. Over time, solar PV emissions tend to decrease because of the improvements in the system efficiency while nuclear energy emissions tend to increase because of decreasing uranium ore grades.
Thirdly, evaluation of economic performance of both technologies was carried out by using LCOE tool. DCF method was used to bring the future costs to NPV and after calculating LCOE, a sensitivity analysis was performed to know the influential parameters. Under the defined system boundaries, LCOE of solar PV was estimated to be 0.045 USD/kWh in which 85% of the costs are capital costs. whereas LCOE of nuclear energy was calculated to be 0.055 USD/kWh in which capital costs and O&M costs account to 50 and 37% respectively. Over time, the LCOE of solar energy tends to decrease with improvements in technology while LCOE of nuclear tend to increase because of the increasing safety standards and inflation.
Lastly, an MCDA method, weighted sum approach was chosen for integration of two aspects as it provides platform for stakeholder participation and provides a transparent, inclusive and organised framework. Three scenarios were considered in which even extreme weights were considered for calculation of sustainability scores and the overall ranking of technologies remained same in the given scenarios. Clearly, solar energy is the winner in the range of the assumed extreme weights and is followed by nuclear and coal energy.
Based on the outcomes of LCA and MCDA of this study, policy implications were discussed. On economic front, electricity bundling of solar and nuclear energy is recommended to reduce the overall cost and to solve the issue of intermittency of solar energy. On the environmental front, GHG hotspot phases in both solar PV and nuclear energy were identified and policy recommendations were discussed. Overall, policies should be aimed at lowering or phasing out the fossil fuels and at providing enabling environment for increasing the low carbon technologies into the energy mix.
As far as LCA and MCDA framework in this research is concerned, the sustainability scores of the technologies help ranking the technologies. More than ranking the technologies, the deliberative process makes stakeholders come together on a platform to formulate problem, discuss trade-offs and come up with unique solutions to reduce the impacts. NITI Aayog can use the framework not only for the case of Maharashtra, but also for different states. The framework allows to arrive at a customised solution according to the preferences of all stakeholders while still be able to measure and compare the improvements in the sustainability aspect.