Energy, Environment and Climate Change

This study investigates the thermal stratification characteristics of a single-medium sensible heat storage tank. The thermal energy storage (TES) system under investigation comprises a vertical cylindrical tank fitted with an immersed discharging coil. The study considers three different discharging coil configurations (helical, conical, and inverted conical). A commercial silicone oil (Hytherm 600) is used as the heat storage medium in the tank, and water serves as the discharging fluid. The thermal characteristics during the simultaneous charging and discharging operation are investigated considering a fixed charging temperature of 90 ℃, an oil flow rate of 1.25 L/min, and two different discharging flow rates (water), 0.5 and 2 L/min, respectively. Results indicate enhanced thermal performance for the helical discharging coil at the discharging flow rate of 2 L/min, with a total discharged energy of 3536.8 kJ, and a discharging efficiency of 54.1%. The highest energy discharged (3546.5 kJ) is realized in the case of the inverted conical coil. However, the losses are higher for this storage configuration, leading to a slightly reduced discharging efficiency (53.6%). The thermocline thickness broadens with increasing water flow rates through the discharging coil side. Eventually, the initial thermocline splits to form a stabilized thermocline thickness of 100 mm in the upper section of the tank for a 2 L/min coil flow rate.

The influence of landslides (LS) on forest structure, composition, and functionality has gained limited scientific attention compared to socioeconomic aspects. This study aims to fill this gap by investigating the dynamics of pre- and post-LS occurrences in and around the Kali Tiger Reserve (KTR), Western Ghats. Our approach integrates multi-source, multi-temporal earth observation data, vegetation indices, field observations, and machine learning techniques. This study identified 245-LS caused due to a catastrophic rainfall event in July 2021 the most severe over a century that impacted the tropical dense forests. The present study highlights the emergence of invasive alien species (IAS), particularly Chromolaena odorata, following these landslide incidents. Field observations revealed a significant loss of large trees, which corroborated with the Global Ecosystem Dynamics Investigation (GEDI) based Canopy Height Model (CHM) and very high-resolution (VHR) data. The affected areas witnessed a significant rise in land surface temperature (LST) and a decrease in vegetation moisture. A comparative analysis  with operational tree loss monitoring using optical (30-m Landsat based Global Forest Watch (GFW), and microwave (L-band Synthetic Aperture Radar (SAR) JICA-JAXA (ALOS-2) Forest Early Warning System) revealed improved performance in mapping small landslides with current approach. These results emphasize the necessity of conducting local and large scale investigations of forest dynamics before and after landslides to meet environmental commitments at various levels. The landslide events will likely induce significant alterations in the forest's microclimate. Our research recommends an immediate action plan to restore affected sites, remove IAS, and encourage the planting of native vegetation for biodiversity conservation.

This paper analyses 556 model scenarios assessed by IPCC’s Working Group-III for the 6th Assessment Report, which have an underlying 10-region classification and correspond to restricting warming levels to 1.5 ℃ and 2 ℃. We show that across all scenarios, the current global inequalities in incomes, energy use, and emissions, are projected to continue even in 2050. Scenarios also project higher per capita fossil fuel use and lower carbon dioxide removal in developed countries in 2050 compared to developing countries. Our results demonstrate the scale and scope of unequal outcomes in these scenarios, that have been anticipated by theoretical critiques of the underlying models. The paper explores the potential reasons for the unequal outcomes of the scenarios focusing on the two key issues of scenario design and modelling framework. Our analysis also suggests that instead of summary assessments focusing on singular median values or percentile ranges, as undertaken in the IPCC report, more could be learned from focusing on differences between models or considering outliers that could present new and innovative solutions to the determination of equitable and efficient future mitigation pathways. Our analysis underlines the need for new frameworks for emissions modelling and scenario building, for constructing possible futures that can also foreground equity and climate justice.

Given India’s continued dependence on coal to supply 24x7 power for industrial and residential consumers at affordable prices, the country needs a unified Coal Mines Environment Authority staffed with multi-disciplinary expertise to assess and minimize the adverse environmental impacts of coal mines with an integrated approach to ensure more efficient, effective and transparent environmental governance.

Given India’s continued dependence on coal to supply 24x7 power for industrial and residential consumers at affordable prices, the country needs a unified Coal Mines Environment Authority staffed with multi-disciplinary expertise to assess and minimize the adverse environmental impacts of coal mines with an integrated approach to ensure more efficient, effective and transparent environmental governance.

The levelized cost of electricity (LCOE) and environmental advantages of coal-CSP hybrid systems are presented by simulating the hybrid system in two modes at three locations in India with contrasting DNI profiles. The cost of additional energy generated due to SAFWH in booster mode is up to 51.4% less as compared to a stand-alone CSP. In the fuel saver mode, up to 40 thousand tons of coal can be annually saved with SAFWH, thus reducing CO2 emissions by 1.7% as compared to a stand-alone coal-fired plant.

The levelized cost of electricity (LCOE) and environmental advantages of coal-CSP hybrid systems are presented by simulating the hybrid system in two modes at three locations in India with contrasting DNI profiles. The cost of additional energy generated due to SAFWH in booster mode is up to 51.4% less as compared to a stand-alone CSP. In the fuel saver mode, up to 40 thousand tons of coal can be annually saved with SAFWH, thus reducing CO2 emissions by 1.7% as compared to a stand-alone coal-fired plant.

Coal mines must incorporate social and ecological sensitivities from the planning stage up to mine closure to meet India’s Sustainable Development Goals. The Normalized Vegetation Difference Index (NDVI) is useful to assess the environmental impacts of mining operations on the air quality and vegetation around coal mines and monitor the progress of post-closure activities.

Coal mines must incorporate social and ecological sensitivities from the planning stage up to mine closure to meet India’s Sustainable Development Goals. The Normalized Vegetation Difference Index (NDVI) is useful to assess the environmental impacts of mining operations on the air quality and vegetation around coal mines and monitor the progress of post-closure activities.

The performance of the State-owned electricity distribution companies (DISCOMs) that distribute 96% of the electricity in India is critical for the country’s energy security. However, the current studies are not suitable for assessing the performance of India’s DISCOMs in an integrated manner since their underlying models are fragmented. This study presents the development and application of an integrated FOBC framework which is a balanced scorecard including 32 key performance indicators related to finance, operations, business processes, and customer service. This framework is used to benchmark the performance of 40 DISCOMs in 17 States on a like-to-like basis leading to the identification of nine DISCOMs for restructuring. The FOBC framework can be used by the regulators and the government to benchmark DISCOM performance in a holistic manner. This study will be useful for policymakers to implement power distribution sector reforms to enhance energy security while decarbonizing the power sector efficiently.

The 2030 Agenda for Sustainable Development, under Goal 6 (SDG 6), aims to ensure universal access to water and sanitation. SDG-6.1 focuses on achieving safe drinking water for all by 2030. India's Jal Jeevan Mission (JJM) targets providing tap water to rural households by 2024. This article discusses a study on water demand and availability in seven villages in Ballari and Raichur districts, North Karnataka. It reveals heavy reliance on groundwater due to inadequate surface water. Only 14% of households meet JJM standards, with projected worsening scarcity. The authors recommended a revised Krishna (Almatti)–Pennar river interlinking project by 2030 to minimize environmental and social impact, which is crucial for North Karnataka's sustainable development.

The 2030 Agenda for Sustainable Development includes Goal 6 (SDG 6): ‘Ensure availability and sustainable management of water and sanitation for all’. SDG target 6.1 aims to achieve by 2030 ‘universal and equitable access to safe and affordable drinking water for all’. The Government of India has also launched the Jal Jeevan Mission (JJM) to provide potable tap water to every rural household by 2024. In this context, this article explains the findings of a study to assess the domestic water demand and the availability of water in seven villages in the Ballari and Raichur districts in North Karnataka. This study indicates that groundwater is predominantly used for domestic purposes in these districts due to the lack of adequate and reliable surface water. Only 14% of households in the study area receive adequate water as per the JJM norms and this water stress is projected to worsen due to the increasing supply–demand mismatch in the future. The authors recommend the implementation of the revised configuration of the Krishna (Almatti)–Pennar river interlinking project by 2030 since this alignment is optimised to reduce project-related deforestation, people displacement, project duration and costs. This is critical for the sustainable development of North Karnataka.

Thermochemical energy storage is emerging as a promising seasonal thermal energy storage technology. Strontium Bromide has recently become one of the most used salt hydrates for the salt-hydrate and moist airbased open thermochemical energy storage system. This article suggests that radial flow fixed bed reactors offer advantageous configurations owing to their lower pressure drop without compromising thermal performance. Four possible configurations of radial flow fixed bed reactors, Inward flow Π-type, Inward flow Z-type, Outward flow Π-type, and Outward flow Z-type, are analyzed in detail. Energy efficiency, exergy efficiency, pressure drop, and non-dimensional constant named non-uniformity are used as performance metrics for comparing the proposed configurations with four different combinations of flow rates and aspect ratios. It is found that the type of the reactor configuration (Π-type or Z-type) has a negligible impact on the performance, with a maximum change of 4% in the energy efficiency during the hydration phase. The inward and outward flow arrangements exhibit considerable differences in performance, with inward flow having 3.5 times higher exergy efficiency than outward flow. The π-type configuration shows the highest non-uniformity of -0.22 for an aspect ratio of four, with a flow rate of 50 m3/h.

This study experimentally investigates the scarcely studied stratified, oil-based sensible thermal energy storage (STES) tank, to examine the heat retention capability of Hytherm-600 silicone oil during the standalone period and its heat dispatchability during the discharging process. To conduct an experimental study on the thermic oil, a vertical cylindrical tank with a helical discharging coil fitted inside is used. Three different oil charging temperatures (50, 70, and 90 °C), and three different discharging flow rates (water) through the helical coil (0.5, 1.25, and 2 L/min) have been considered. The thermal stratification phenomena in oil and the evolution of thermocline have been investigated. Results indicate the formation of a thermocline zone of 154 mm thickness in the lower portion of the tank within 3 h from the commencement of the stand-alone period. The discharging operation fluctuates the thermocline stability in the storage medium (i.e., commercial thermic oil Hytherm-600). During the discharging operation, a water flow rate of 0.5 L/min through the helical coil led to higher discharging efficiencies owing to better heat transfer attributable to the higher water residence time inside the coil. For the aforesaid water flow rate, the average discharging efficiencies are 85.6%, 75.6%, and 81.6% for the charging temperatures of 50, 70, and 90 °C, respectively. Finally, the primary thermocline thickness is found to be constant at 82 mm following the splitting of the initial thermocline during the discharging operation.

A large-scale socio-cultural transition such as the ‘shift toward eCooking’ is a process (or a journey) rather than a destination. Apart from the business potential it offers, it would potentially create a large number of aware and educated citizens. Strengthening appliance and vessel manufacture would reinforce the country’s domestic MSME sector. Improved eCooking appliance safety culture would enhance manufacturers’ competitiveness (and also acceptability) globally. Academic training on energy efficiency, environmental benefits, nutritional benefits associated with eCooking, and hands-on training for appliance manufacturing, demonstration, servicing, and repairing, will lead to large capacity building in the country. The formation of efficient public relations channels would help improve the transparency of communication across the whole ecosystem encompassing industry, entrepreneurs, innovators, educators, policymakers, and consumers.

Methane (CH4) is one of the most abundant organic trace gases in the atmosphere having a strong global warming potential of 28 in 100 years, is a significant GHGs, and has a vital role in atmospheric chemistry and climate change. India is home to the largest number of livestock in the world and is responsible for higher methane emissions from enteric fermentation and manure management. In the present study, the methane emissions from Indian livestock, i.e., enteric fermentation, is estimated to be 11.63 Tg yr-1 in 2019 using IPCC methodology and recent census livestock activity data from the Department of Animal Husbandry and Dairying, Govt. of India, and corresponding country-specific revised emission factors. The CH4 emissions from livestock manure management system was found to be 1.11 Tg yr-1, resulting in 12.74 Tg yr-1 of CH4 emission from the Indian livestock sector. The district-level spatial CH4 emission pattern was developed to identify the potential emission hotspots across the country. Initial findings suggest that changing livestock population patterns plays an important role in governing methane emissions in rural India. The information generated could be important tools for policymakers to control methane emissions across the country.

Hazardous pollutants like Mercury (Hg) have emerged as a pressing challenge in recent times where the expanding industrial sector is regarded as the major source in developing country India. In this study, we are trying to identify all possible industrial sectors at district level to quantify Hg emission load across India for the year 2019 using IPCC methodology where the country-specific technological emission factors are used. We have included 5 major sectors out of which emission from coal combustion in thermal power plants accounts for 186.5 t/yr of Hg emission followed by non-ferrous metal production (88.3 t/yr), captive power plants (65.5 t/yr) and fly ash generation from various manufacturing industries (45.9 t/yr). A total of 459.4 t/yr of Hg is released into the ecosystem in 2019 with an uncertainty of ± 48%. This study also estimated that about 233 million people living in and around 10 km periphery of major industrial zones with as many as 17 million people residing near the 10 major hotspots are susceptible to hazardous Hg emissions directly or indirectly. This information would be quite useful in formulating future Hg emission control strategies in India.

The 2030 Agenda for Sustainable Development, under Goal 6 (SDG 6), aims to ensure universal access to water and sanitation. SDG-6.1 focuses on achieving safe drinking water for all by 2030. India's Jal Jeevan Mission (JJM) targets providing tap water to rural households by 2024. This article discusses a study on water demand and availability in seven villages in Ballari and Raichur districts, North Karnataka. It reveals heavy reliance on groundwater due to inadequate surface water. Only 14% of households meet JJM standards, with projected worsening scarcity. The authors recommended a revised Krishna (Almatti)–Pennar river interlinking project by 2030 to minimize environmental and social impact, which is crucial for North Karnataka's sustainable development.

The renowned seismologists C.P. Rajendran and Kusala Rajendran offer a riveting story of the Indian earthquakes, their science, history and impact. Like all other natural phenomena, earthquakes are part of life-sustaining forces-- the creators of the mountains, valleys and springs or even deserts on Earth-- a theatre where the show never ends.

The book takes the readers to some exciting parts of India to show how earthquakes change the topography where a sea existed not far in the past-- now a salt marsh, affecting the social life, trade and livelihood. The book discusses the likelihood of the next big earthquake in the Himalayas against the backdrop of the devastating earlier ones revealed by archaeology, history and geology. It probes the causes and aftermath of the devastating Indian Ocean tsunami of 2004 and gives a glimpse of the past.

The high-impact earthquakes will happen, but they need not always end up as human catastrophes. The authors have spent much of their professional lives studying the earthquakes in India and abroad. They tell us from their vast experience how to negotiate the impacts of earthquakes and related hazards by following science-based strategies.

The green mobility aspirations of India have necessitated substituting conventional vehicles with electric motor-driven counterparts. The rare earth permanent magnet-based motor is the dominant solution for electric vehicle motor architectures as it ensures energy efficiency with reduced kerb weight and increased vehicle range. This study estimates the magnet-based rare earth demand for the realistic aspirational growth trajectories of electric four-wheelers up to 2030. During the first phase (2021-25), a high year-on-year growth rate for the e-car segment is assumed, which creates the base for electric vehicle penetration, whilst the second phase (2026-30) envisages a rapid product substitution at the cumulative level by 2030. The estimated total demand for rare earth materials during 2021-30 is between 1434 and 3584 tonnes. Analysis indicates that India could leverage its strong position in the global automotive market and geopolitical proximity to the favourable global powers for collaboration in research and development, technology transfer, and securing raw material supply.

Simultaneous charging and discharging operations of thermal energy storages render effective energy-harnessing features. However, it leads to thermocline formation due to the dynamic interplay between energy input, energy extraction, and losses. Reliable retention of good thermodynamic quality of energy is realized by minimizing the energy degradation and thermocline thickness. Near real-time tracking of heat content degradation is a tedious task for real-sized storage systems, which involves accurate quantification of the temporal evolution of thermocline thickness. A few simplified, one-dimensional energy-based models are available for tracking the movement of the thermocline layer inside the thermal energy storage tank. However, these models largely assume the thermocline layer to be a thin horizontal plane within the tank, without quantifying the thermocline thickness. In this study, a reduced-order realistic stratification (RS) model has been developed for the vertical cylindrical tank equipped with an immersed helical discharging coil, working under dual-dynamic mode. For evaluating the thermocline thickness, the prediction equations for the average temperatures in the upper and the lower regions of the tank are formed using a machine-learning-based technique, considering a reasonably wide range of operating and geometrical parameters. The developed model utilizes approximate formulations for the average temperatures of the upper and lower regions of fluid within the storage tank, coil outlet temperature, and the overall average temperature of working fluid. For the larger storage tank (155 L), the thermocline thickness predicted by the new RS model is 738.26 mm at the end of simultaneous charging and discharging operation, whereas that estimated by detailed numerical simulation is 798.12 mm. This improved model reduces the computational time by about 80 % owing to effective approximations and can be used for a reasonably accurate rapid assessment of thermal degradation in the storages deployed for low-temperature solar thermal applications, including domestic hot water systems.

The transition trajectory of India's two-wheeler (2W) vehicle segment is studied using a sequential modelling framework for projecting sub-segment-wise 2W fleet, energy demand, and associated CO2 emissions. Road density per capita was identified as a more significant explanatory variable than GDP per capita in estimating 2W fleet size in India. The elasticity method was used to evaluate the 2W vehicle saturation level based on five different indirect parameters. It was found that population density had the highest impact (48%), followed by urbanization (31%) and adult population share (16%). The impact of the total cost of ownership was negligible. The mean 2W vehicle saturation level was calculated to be 314 while the ownership was found to be 207, 265, and 297 vehicles per 1000 people by 2030, 2040, and 2050, respectively. Scooters were found to be leading the e-transition of 2Ws but a successful e-transition of India's 2Ws would not be achieved without transitioning the motorcycles. Two motorcycle clusters were identified that offer economies of scale towards e-transitioning. Closer scrutiny of six plausible e-transition scenarios showed that a 50% penetration of E−2Ws is unattainable before 2045. The biggest obstacle in achieving high E−2W penetration in India would be the limited capacity to supply indigenously produced vehicles. A high import dependence on battery technology and critical raw materials would limit the energy transition and diversification of the Indian road transport sector. India should follow the mass adoption-driven diffusion pathway in the short-to-medium term and the affordability-constraint diffusion pathway in the long term to achieve the best results in terms of reduction in energy demand and associated emissions for the 2W segment. The gains from the e-transition of the road transport sector would not be substantial without a simultaneous transition in the country's electricity generation mix away from coal-based thermal power.

In this study, the evaluation of carbonaceous fine particulate matter (C-PM) was conducted using the SAFAR-India regional model. Two emission inventories were utilized: the newly developed SAFAR inventory and the global EDGAR-HTAP inventory, both for the year 2018. The simulation aimed to capture the seasonal and spatial patterns of black carbon (BC) and organic carbon (OC) concentrations. To validate model results, surface meteorological parameters, and C-PM concentrations were compared with the MERRA reanalysis data for the Indian region. Model simulated surface C-PM concentration with SAFAR emission inventory is found to be slightly overestimated (1.10), whereas simulated results with EDGAR emission inventory is significantly underestimated as compared to MERRA data. Model-simulated meteorological parameters showed a better correlation with MERRA reanalysis. Simulated geographical patterns of seasonal mean C-PM with SAFAR emission inventory exhibit quite a better comparison with MERRA reanalysis as against EDGAR simulated results. However, some differences in the present results are visible, particularly over the IGP region, as compared to MERRA data, but they are mainly attributed to a significant difference in the special resolution of present results (much finer) as compared to coarser MERRA data. In the Indo-Gangetic Plain (IGP) region, the concentration of BCSF and OCSF (BC and OC with SAFAR emission, respectively) show the peak during the winter, followed by the post-monsoon season. Although the correlation coefficients of hourly time series of surface BCSF and OCSF concentrations with MERRA over India are high (0.92 and 0.88), the poor RMSE, is attributed mainly to different scales of resolution. The model simulated BC, and OC concentrations with SAFAR emission input capture the pattern of spatial distribution reasonably well. The present evolution of BC and OC will help to better quantify their impact on climate and atmospheric conditions over the Indian region.

The escalated demand for rare earth materials is anticipated as a major roadblock to the aspirational ‘green and energy-efficient transition’ since it could lead to raw material shortage. Therefore, recycling essential components from the air conditioner units is envisaged as a suitable solution for sustaining the product supply chain.

The Variable Energy Cyclotron Center (VECC) at Kolkata has a K130 room-temperature cyclotron that has been operating since 1977, a K500 Cyclotron operating since 2009, a K30 medical cyclotron and a radioactive ion beam facililty. It has a large number of very high voltage or very high current power supplies, liquid helium plants, and very many vacuum pumps sophisticated and delicate equipment. Yet, in the last more than 5 decades of its operation there have been no serious accidents or leakage of radioactivity. This has been possible by a strict regime of retraining and strict adherence to standard security precaution, and an active and understanding leadership. This chapter describes some of these efforts.

This study evaluates the performance of the vertical cylindrical annular reactor configuration, considering innovative radial airflow configurations. From a detailed parametric study, the most suitable reactor geometry and flow arrangement have been identified based on standard performance metrics.

Considering the need to identify the sources of air pollution in smart city Bhubaneswar, a non-attainment city in India, a high-resolution comprehensive gridded emission inventory (EI) of eight primary air pollutants has been developed for the base year 2018. The inventory involves detailed activity data with ~0.4 km × ~0.4 km resolution covering the city using a Geographical Information System (GIS) based statistical approach. In total, ~17 major and minor sectors are responsible for the city’s air pollution crisis. Windblown road dust, transport sector, and residential cooking activities emerged as the dominating sources. Emissions of CO, NOx, SO2, VOC, PM2.5, PM10, BC, and OC are estimated to be 112 Gg yr–1, 44 Gg yr–1, 11 Gg yr–1, 73 Gg yr–1, 9 Gg yr–1, 17 Gg yr–1, 5 Gg yr–1 and 0.8 Gg yr–1 respectively. Nearly 14% and 12% area of the entire study domain are found to be responsible for almost half of PM10 and NOx emissions respectively. The central region of the city with the presence of national highways, major roads, and nearby industrial belts, experiences maximum emission of pollutants. The present gridded surface emission dataset is an essential requirement in framing new mitigation strategies to combat ongoing and future air pollution crises and achieve better air quality.

The Indian capital megacity of Delhi is reeling under deteriorating air quality, and control measures are not yielding any significant changes, mainly due to a poor understanding of sources of emissions; hence, priority option in mitigation planning is lacking. In this paper, we have made an attempt to develop a spatially resolved technological high-resolution gridded () emission inventory for eight major pollutants of the Delhi region where high-resolution activity data of all possible major and unattended minor sources are generated by organizing a mega-campaign involving hundreds of volunteers. It is for the first time that we are able to estimate the decadal growth in emissions of various pollutants by comparing newly developed 2020 emissions with SAFAR (System of Air Quality and Weather Forecasting and Research) emissions of 2010 using the identical methodology and quantum of activity data. The estimated annual emissions for PM2.5, PM10, CO, NOx, VOC, SO2, BC, and OC over the Delhi National Capital Region (NCR) are estimated to be 123.8, 243.6, 799.0, 488.9, 730.0, 425.8, 33.6, and 20.3 Gg yr−1, respectively, for the year 2020. The decadal growth (2010–2020) in PM2.5 and PM10 is found to be marginal at 31 % and 3 %, respectively. The maximum growth is found to be in the transport sector followed by the industrial and other sectors. Maximum decadal growth found for the pollutants BC, OC, and NOx is 57 %, 34 %, and 91 %, respectively. The decadal shift of sectorial emissions with changing policies is examined. The complete dataset is available on Zenodo at https://doi.org/10.5281/zenodo.7715595 (Sahu et al., 2023).

Saroj Kumar Sahu, Poonam Mangaraj

The performance of the State-owned electricity distribution companies (DISCOMs) that distribute 96% of the electricity in India is critical for the country’s energy security. However, the current studies are not suitable for assessing the performance of India’s DISCOMs in an integrated manner since their underlying models are fragmented. This study presents the development and application of an integrated FOBC framework which is a balanced scorecard including 32 key performance indicators related to finance, operations, business processes, and customer service. This framework is used to benchmark the performance of 40 DISCOMs in 17 States on a like-to-like basis leading to the identification of nine DISCOMs for restructuring. The FOBC framework can be used by the regulators and the government to benchmark DISCOM performance in a holistic manner. This study will be useful for policymakers to implement power distribution sector reforms to enhance energy security while decarbonizing the power sector efficiently.

 It is necessary to consider alternate fuels for ICE-based vehicles to achieve decarbonization in India’s road transport sector. This study discusses the ICE-based alternate fuel options (natural gas, auto-gas and hydrogen) in the light of 28 identified parameters under the 4A framework of energy security, encompassing technical availability, resource availability, infrastructure accessibility, price affordability, social acceptability and environmental acceptability.

Air pollution is serious and most talked about issue in India as impacts are fast realized in a shorter time, unlike climate change. North India including the Indian capital experience extreme levels of pollution during winters due to extreme weather compounded by biomass burning episodes. On the other hand, Western India often witnesses pollution extremes during summer due to intercontinental dust flows whereas the peninsular and east India relatively remain better, but the frequency of weather extremes is increasing, and climate change is impacting the delicate balance. It is resulting in deteriorating health and food security. The problem is well recognized, but information and actions are fragmented warranting an integrated approach to build a resource framework for air quality in a mission mode. Network of specialists working on various aspects of air pollution and knowledge sharing for optimal and broad-scale results that benefit all. To address this gap, the National Institute of Advanced Study (NIAS, IISc Campus, Bengaluru) organized the brainstorming workshop for stakeholders along with the office of Principal Scientific Advisor to Govt. of India to help develop pathways for dialogue and knowledge sharing for air pollution information, alerts, capacity building, effective mitigation, and policy at the national level. The current strategic document is an outcome of this effort. This NARFI aims to build an integrated framework in air quality for a sustainable future by bringing together researchers, practitioners, and experts from diverse sectors and disciplines – air quality monitoring, health, and social inclusion, livelihoods, knowledge management, and communication, as well as those dealing with open burning, transport sectors, etc. Also, regional pollution issues like stubble burning, smog, and fog –to share their knowledge and experience on air pollution. The framework will support the public-industry partnership in air quality management that has the potential to influence decision-makers.

The auxiliary power required in the form of electrical energy for blowing the air through the packed bed reactor is an important consideration since it depends on various design parameters of the system. A radial flow annular reactor configuration is proposed in the present study. It shows a 65%-80% reduction in the flow work requirement. The parameters, such as the flow direction and flow rate, need to be optimized for better performance and to ensure lesser flow work requirements.

The nature and origin of organic aerosol in the atmosphere remain unclear. Paper proposes a mechanism and parameterization of them in a high resolution air quality model for India for improved accuracy.

First National level emission inventory development of Toxic Greenhouse gas Black Carbon (BC) and regular pollutant Organic Carbon (OC). The BC has double wampy, a greenhouse gas for climate change and deadly pollutant for health

Fine particulate matter (PM2.5) pollution is a primary global public health concern. Exposure to PM2.5 pollution beyond the safe limits of exposure is associated inter alia with respiratory and cardio-vascular mortality and morbidity. However, the baseline and background levels of PM2.5 concentration in megacities in India are significantly higher than the WHO Air Quality Guidelines which are based on studies conducted in regions with very low ambient PM concentrations. Human susceptibility to air pollution may vary based on age distribution, nutritional intake, access to health care, meteorological conditions, and any natural immunity. Therefore, it is essential to study the exposure-response function(s) specific to India using the local air pollution exposure studies.

On the other hand, the air quality monitoring stations used to measure ambient PM2.5 concentration are sparse and non-uniformly distributed in urban areas and nearly-absent in rural areas leading to the misclassification of exposure in India.

Therefore, the authors have developed a Linear Mixed Effects model in the present study to estimate PM2.5 levels in four major cities in peninsular India at a spatial resolution of 1 km x 1 km. Bengaluru (801 grids), Hyderabad (873 grids), Madurai (81 grids), and Vijayawada (88 grids) have been selected for this study since they are useful to estimate air pollution exposures for cities with different geographical, climatical, demographic and topographical conditions.

dictate the efficacy of low-to-medium temperature hot water applications. This study uses a three-dimensional
numerical model to investigate the thermal characteristics of three storage configurations for simultaneous
charging and discharging. The same tank volume and height, as well as the same coil tube dimensions, are
considered for three different configurations - cylindrical tank with a helical discharging coil, as well as circular
truncated cone-shaped and paraboloidal tanks with conical discharging coils. The discharging flow rate is varied
for a deeper understanding of the realistic interplay between energy demand and supply. Results obtained for the
cylindrical tank are found to have good agreement with the observations from the in-house experiments. The
energy stored, discharging coil outlet temperature, and the extent of thermal stratification decrease with
increasing coil flow rate, whilst discharging efficiency and primary thermocline thickness increase. The paraboloidal
tank equipped with a conical discharging coil exhibited the highest cumulative energy stored (8821 kJ)
just before the commencement of dynamic dual operation, owing to the minimal thermal losses attributable to
the lowest surface-area-to-volume ratio. Thermocline thickness is found to expand with time for all the cases, and
the highest thermocline thickness expansion rate of 0.208 mm/s is found for the cylindrical tank indicating a
higher degree of energy degradation. The peak values for the cumulative energy discharged (9788 kJ), and
average discharging efficiency (0.36) occurred for the paraboloidal tank with the conical discharging coil
configuration. Based on the detailed analyses, the paraboloidal storage tank configuration is found to exhibit
better system reliability and energy management, leading to more efficient heat dispatch controllability due to
the enhanced energy harnessing features.

Air quality and health co-benefits of climate change mitigation and adaptation actions by 2030: An interdisciplinary modelling study in Ahmedabad, India

Traditionally coal has been extensively used as a dominating fossil fuel in a wide range of industries due to its abundance. In India, industries like thermal power plants, cement industries, iron, and steel industries along with many captive power plants consume a huge quantity of coal each year to meet energy demand. The potential radionuclide hotspot regions across the nation are identified, which could be used as an important tool to assess its impact on the chronic exposure of millions of residents living near these sources. Cleaner or green energy could be the best alternative to combat the unseen health disaster. More effective and safe utilization of fly ash can minimize the hazardous effect of radionuclides emission.

Near real-time monitoring of major air pollutants, i.e., particulate matter (PM10, PM2.5, PM1), trace gases (O3, CO, NO, NO2, NOx, NH3, CO2, SO2) and Volatile Organic Compounds (VOCs: benzene, ethylbenzene, m-, p-xylene, o-xylene and toluene) along with climatological parameters was done in eight-cities field campaigns during the rabi (wheat) crop residue burning period in the northwest of Indo-Gangetic Plain (IGP) region. This multi-city study observed that semi-urban regions have the most compromised air quality during the rabi crop residue burning and need attention to address the air quality issues in the IGP region.

Coal-based power generation in the EU will increase for the second consecutive year in 2022 after recording an increase of 20% in 2021 while natural gas production in the U.S. during 2022 has reached an all-time high of 2.7 billion cubic meters per day. India depends on coal for 72% of its electricity generation and it is critical for the country to expedite medium-term and long-term strategies to ensure the sustainability of India’s coal & power sectors without hampering our energy security and human development. These strategies are explained in this report.

Our analysis of IPCC Sixth Assessment scenarios shows that they disregard both the historical responsibility of the Global North for carbon emissions as well as the future energy needs of the Global South required to meet developmental goals. The burden of climate change mitigation is placed squarely on less developed countries, while developed countries continue to increase their energy consumption unhindered by constraints on the use of fossil fuels.

At the COP 27 summit in Sharm El Sheikh, Egypt (beginning November 6, 2022), the global South must put the question of its energy poverty and the severe global inequalities in energy access squarely at the centre of all discussions.

At the COP 27 summit in Sharm El Sheikh, Egypt (beginning November 6, 2022), the global South must put the question of its energy poverty and the severe global inequalities in energy access squarely at the centre of all discussions.

The Permanent Court of Arbitration (PCA) acted as a registry in four inter-state proceedings, 105 investor-state arbitrations, and sixty-five cases under contracts or other agreements involving a state or other public entities in 2021. The cases with environmental and natural resource aspects are addressed and highlighted in this study. 

Coal mines must incorporate social and ecological sensitivities from the planning stage up to mine closure to meet India’s Sustainable Development Goals. The Normalized Vegetation Difference Index (NDVI) is useful to assess the environmental impacts of mining operations on the air quality and vegetation around coal mines and monitor the progress of post-closure activities.

The increase in Sun’s Ultraviolet radiation flux during lockdown led to reduced infections and death as the UV radiation breaks the genetic structure of the SARS-CoV-2 virus and deactivates it. 

The accumulated losses of all State-owned power distribution companies (DISCOMs) have crossed Rs.5 lakh crore even after more than Rs.2 Trillion of their debt was taken over by the respective State Governments in FY 2015-16. The Government of India wants to pump in another Rs.3 trillion into these DISCOMs. This approach flags serious managerial deficiencies within the State-owned DISCOMs and the effectiveness of the electricity regulators in India. This report summarises the deliberations in a NIAS stakeholder consultation workshop. and the way forward for the power distribution sector.

The levelized cost of electricity (LCOE) and environmental advantages of coal-CSP hybrid systems are presented by simulating the hybrid system in two modes at three locations in India with contrasting DNI profiles. The cost of additional energy generated due to SAFWH in booster mode is up to 51.4% less as compared to a stand-alone CSP. In the fuel saver mode, up to 40 thousand tons of coal can be annually saved with SAFWH, thus reducing CO2 emissions by 1.7% as compared to a stand-alone coal-fired plant.

The study describes the creation of four simple metrics to estimate: 1. the ratio of ‘green’ vegetated areas to the ‘blue’ water spread areas, defined as the ‘Green-blue ratio’ (GBA); 2. The ratio of ‘blue’ water spread areas to ‘built-up’ ratio around the lakes, defined as the ‘Blue to Built-up ratio’ (BBA), 3. the percentage of impervious surface area (ISA) and 4. the pace of urbanisation in the dynamic zones (DZ) of urban lake environments.

A case study from Odisha, India on the socio-technical constraints among fishers to utilise the services of marine fishery advisories provided to them.

An analysis of the transformational processes, habitat fragmentation and resilience of Pulicat lake, India, a coastal ecosystem is presented in this co-authored publication. 

This edited book discusses Blue-Green Infrastructure (BGI) from conception to implementation in building resilience and urban sustainability. The book emphasizes on infrastructures, institutions, and perceptions as three main pillars of implementing and managing successful BGI, with a special focus on Asia.

India's overambitious targets for solar energy could destabilize its power sector and threaten energy security. Rather than 'green' political posturing, the country must plan an energy transition based on its developmental interests.

The present work reports the actual ground conditions prevalent at a fish landing center in Northern Odisha, namely, Talsari in the aftermath of the cyclone “Yaas”, which made landfall on May 26th, 2021. The coastal vulnerability and the impacts of the cyclone are discussed.

Power generation from Thermal Power Plants (TPP) in India forms the backbone of the power system. In this study, the dispersion of particulate matter and sulphur dioxide from a TPP with a 275 m-high stack are studied under different atmospheric conditions up to a distance of 30 km from the stack. Based on the results, policy changes that need to be implemented are suggested.

The dynamic performance of a hybrid power plant configuration comprising of a ground heat exchanger and an organic Rankine cycle (ORC) for power generation at the load end is studied. The simulation of dynamic characteristics demonstrates that the proposed geothermal-ORC hybrid system is capable of producing a steady power output of approximately 86.3 kWt. The exergy efficiency of U-shaped BHE without insulation is found to be the maximum.

This paper analyses the power supply situation in Southern India for the year 2018 to evaluate the impact of renewable energy policies on energy costs and the resulting cost of avoided carbon. An optimization model is built using GAMS. Validating the model results against actual data for the year 2018 suggests that regulatory constraints and policy interventions have reduced the solution space for reasonable cost-based optimization in Southern India.

Given India’s continued dependence on coal to supply 24x7 power for industrial and residential consumers at affordable prices, the country needs a unified Coal Mines Environment Authority staffed with multi-disciplinary expertise to assess and minimize the adverse environmental impacts of coal mines with an integrated approach to ensure more efficient, effective and transparent environmental governance.

The World Health Organization (WHO) recently (Sep 2021) released its revised Air Quality Guidelines (AQGs) which have been made more stringent compared to their earlier guidelines. This raises the question whether India’s National Ambient Air Quality Standards (NAAQS) notified by the MoEFCC in 2009 are adequate and whether the revised WHO AQGs are relevant for India. The natural corollary to this is to identify the policies and actions required to strengthen the science of risk assessment and develop rational estimates of mortality and morbidity attributed to air pollution amongst the population in India. These issues have been examined in the NIAS Policy Brief to recommend the way forward.

The levelized cost of electricity (LCOE) and environmental advantages of coal-CSP hybrid systems are presented by simulating the hybrid system in two modes at three locations in India with contrasting DNI profiles. The cost of additional energy generated due to SAFWH in booster mode is up to 51.4% less as compared to a stand-alone CSP. In the fuel saver mode, up to 40 thousand tons of coal can be annually saved with SAFWH, thus reducing CO2 emissions by 1.7% as compared to a stand-alone coal-fired plant.

The authors propose a “Sustainable Coal Mining (SCM) Bill” to constitute a unified authority named “Coal Mines Environment Authority” to enhance the effectiveness, efficiency, and transparency of the environmental regulation of coal mines. Besides the draft SCM Bill, the authors also explain the enabling amendments required in the existing environment, forest, and mining Laws to enact the SCM Bill.

This report describes the research conducted by NIAS to develop an optimal transition plan for India’s power sector and concludes with policy recommendations for an orderly transition to a more environment-friendly generation mix for South India by 2030.

The research report focuses on the Spatio-temporal trends in air quality, vegetation, and water quality before, during, and after the closure of opencast coal mines in India. Besides, Aerosol Optical Depth and Normalised Difference Vegetation Index have also been extracted to study the long-term trends in Particulate Matter concentrations and vegetation cover, respectively. The report concludes with policy recommendations to improve the sustainability of the coal sector.

The NIAS Transition plan for India’s power sector involving the progressive retirement of 36 GW of capacity in 211 obsolete Thermal Power Plants (TPP)s based on key performance parameters and shifting their load to upcoming modern TPPs and Nuclear Power Plants. Implementation of the NIAS Transition Plan will enable the National Grid to meet the peak demand up to March 2030 with lower Capex and tariffs while reducing coal consumption, water requirement, air pollution, and CO2 emissions.

Power distribution companies (DISCOMs) in India are experiencing financial stress. The high cost of power procurement is one of the key reasons for this financial stress. This is mainly due to a fragmented approach to power sector reforms. The authors offer insights and propose recommendations to address this situation.

Thermal stratification characteristics are investigated and analyzed in detail for three chosen shapes of TES, namely truncated-cone, paraboloid, and cylinder, using a two-dimensional unsteady numerical model. Results of the numerical model on cylindrical TES is found to have good agreement with the findings of the in-house experiments. . At every AR investigated for the two shapes of TES, Richardson number for the paraboloid TES is greater than that of the truncated-cone TES, qualitatively suggesting a better temperature stratification in the paraboloid TES.

As part of a SERB-funded research Project, NIAS drafted proposals for a “Sustainable Coal Mining Bill” and an “Environment, Forest, and Mineral Laws (Amendment) Bill,” to create a unified, empowered, and inter-disciplinary environmental regulator for coal mines. These proposals were discussed during a virtual stakeholder consultation workshop on September 5, 2020.

The paper analyses the proposed Electricity (Amendment) Bill, 2020 which is aimed at reducing subsidies and encouraging privatization, especially in the distribution segment of the power sector. The paper argues that the central government must hold off on passing any hasty legislation on the subject and adopt a more scientific and less ideological approach to deal with the travails of the power sector.

The NIAS Transition Plan for Thermal Power Plants (TPPs) recommends the progressive retirement of obsolete TPPs while shifting the load to existing and under-construction, modern TPPs and Nuclear Power Plants (NPPs) instead of retrofitting them with costly Flue Gas Desulfurisers (FGDs). Stack heights mandated for TPPs in India are designed to disperse SO2 emissions to ensure that ambient air SO2 levels comply with National standards. FGDs must be mandated only for TPPs in urban or sensitive or highly polluted areas since they increase specific CO2 emissions and water requirements and also hike tariffs. TPPs can use washed coal and retrofit high-performance Electrostatic Precipitators to reduce Particulate Matter (PM) emissions by 99.97 per cent without major capex.

This paper analyses the economic impact of Covid-19 in India. It documents the trajectory of infections and the lockdown and evaluates the extent of economic losses due to the lockdown. It also critically assesses the economic response of the Indian government to the pandemic and the lockdown.

In line with the recent research on coastal ecosystems, the present investigation details the changes in environmental parameters modeled as a function of their spatial and temporal distributions (dry and wet seasons) in a transitional aquatic ecosystem in South India, Pulicat lagoon using a geochemical model and saturation indices.

India's overambitious targets for solar energy could destabilize its power sector and threaten energy security. Rather than 'green' political posturing, the country must plan an energy transition based on its developmental interests.

This paper demonstrates the use of a linear Input-Output (IO) model to estimate the economic losses in India due to COVID-19. The results show that depending on the duration of the lockdown, the Indian economy is likely to face a loss of about 10–31% of its GDP. The paper also discusses the impacts of COVID-19 on the demand and supply of electricity and CO2 emissions from the power sector. The cost of avoided carbon is approximately 186–264 $/tCO2.

This paper is an analysis of the economic impact of the Covid-19 pandemic in India. The economic crisis after March 2020 affected all the sectors of the Indian economy and led to a loss of employment to the tune of at least 15 million. Using an Input-Output (I-O) framework, we create four scenarios of losses to the Indian economy. We estimate that India’s GDP growth rate in 2020-2021 may range from –4.3% to –15%.

In this study, a simplified energy equations-based dynamic model is used to develop working relationships for calculating the collector dimensions and the optimum heat transfer fluid (HTF) mass flow rate for achieving a predefined thermal efficiency. The computational results for the geometrical configuration corresponding to an average DNI, calculated from actual solar radiation data, indicate that to achieve a fixed temperature and a collector efficiency, the required HTF mass flow rate increases with an increasing level of solar radiation.