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Quantification of greenhouse gas emissions is a critical research gap for space cooling and refrigeration applications in Indian commercial buildings. This is especially relevant as these services are expected to grow rapidly in future driven by economic growth and urbanisation. This paper focuses on these two applications which are highly energy and emission intensive, and quantifies their carbon dioxide (CO) and hydrofluorocarbon (HFC) emissions through soft-linking a top-down model with a bottom-up approach. An integrated assessment modelling framework Global Change Assessment Model (GCAM)-IIM is used for modelling energy-related emissions under a business-as-usual scenario. In addition to CO emissions occurring from electricity use, cooling and refrigeration in commercial buildings emit another set of highly potent greenhouse gases, emanating from application of HFCs as coolant. HFCs substitute their ozone-depleting precursors in these applications. Countries across the world have agreed to phase down HFCs under the Montreal Protocol. Before we can analyse cost-effective options to bring down these emissions, it is important to quantify and assess the amount of emissions that could be avoided in the future. Our research sets up a baseline for carbon dioxide and HFC emissions from India for the commercial air-conditioning and refrigeration sectors and finds the potential HFC emission mitigation due to the Kigali Amendment. A detailed bottom-up modelling of these emissions is undertaken and it is found that, if unabated, the HFC emissions from commercial sector will surge from mere 1.8 million tonne (Mt) COe in 2015 to 211 Mt COe in 2050, whereas energy-related CO emissions from commercial air-conditioning and refrigeration will rise from 37 to 297 Mt COe in the same period. We also highlight the role of management practices and regulation for curbing HFC emissions which is especially relevant for the commercial building sector. [ABSTRACT FROM AUTHOR]

High temperature and humidity of many reason of India in the summer season is the major challenge for human comfort also in the drying. In the present work, experiments have been performed to examine the cooling and dehumidification process in the summer season for human comfort and industrial application with the help of calcium chloride (CaCl2) based desiccant material solid desiccant wheel integrated with solar heating arrangements. In this study experimental findings are also evaluated by the mathematical model. During the dehumidification of air in the process unit humidity changes from 17.75 to 29.03 g H2O/kg dry air to 2.8–3.9, 6.8–8.15, 8.92–10.9 & 9.79–11.87 g H2O/kg dry air for flow rate at 1, 2, 3 & 4 m/s, respectively. The process air outlet temperature is increased in the range of 2.58–3.53 K for all air flow rates. After humidification of process outlet air, human comfort condition (HCC) is produced with temperature and humidity in the range of 30–33 °C and 7.77–12.47 g H2O/kg dry air for different air flow rates. Overall airflow for velocity 2–4 m/s can be recommended for the HCC condition. The proposed modelled expression indicates less than 10 % error between the actual and modelled value for different sections. [ABSTRACT FROM AUTHOR]

The term “polygeneration” is referred to as “an energy supply system, which delivers more than one form of energy to the final user”, for example: electricity, heating/cooling, desalination can be delivered from polygeneration process. The polygeneration demonstrates unique integration of energy efficiency and renewable energy. It is the next generation energy production technique with a potential to overcome intermittence of renewable energy, reduce cost of power generation and greenhouse gas emissions. The feasibility study of this paper is divided in three sections: In first section of this study, solar and biomass have been arranged to produce steam for power generation. In the second section, cooling is produced by vapor absorption refrigeration (VAR; LiBr-H 2 O) system as per demand load requirement using steam, extracted from pass-out turbine. In the last section of this paper, multi effect dehumidification (MED) water desalination is produced by using limited amount of heat from water vapor (refrigerant; H 2 O) through HE1 of VAR cooling system. [ABSTRACT FROM AUTHOR]

For better use of evaporative cooling techniques in humid climate, a desiccant cooling system (DCS) can be an alternative option in place of a conventional cooling system. This paper presents a theoretical comparative study of the performance of a DCS for four different climatic conditions of India (i.e. hot and dry, warm and humid, moderate and composite climates). From the analysis, it was found that the performance of a DCS is suitable in warm and humid climate. The thermodynamic equations of intermediate states of the desiccant cooling cycle are also presented. Effects of some parameters such as outdoor specific humidity, R/P ratio (regeneration air flow/process air flow) and power required to regenerate the desiccant wheel have been studied. The theoretical minimum R/P ratio has been computed for the maximum coefficient of performance (COP) of a DCS and its value was found to be 0.55 in Mumbai (warm and humid climate) for the 80% effectiveness of ECW. This paper also presents the relationship between COP and regeneration power with the different values of R/P ratios. [ABSTRACT FROM AUTHOR]

Abstract: A lecture theatre with dimension 16m×8.4m×3.6m located at Roorkee (28.58°N, 77.20°E) in the northern region of India, is selected to calculate the monthly and annual cooling load (kWh) and cooling capacity of air conditioning system by a computer simulation. The paper also presents the results of a study investigating the effect of different glazing systems on windows and the reduction in building cooling load. DesignBuilder software has been used for the computer simulation for calculating the cooling load. The paper aims to investigate the reduction in thermal gains and cooling load requirements by varying the U-values of different glazing types, insulating the ceiling, providing cool roofs, interior and exterior insulation on walls, and replacing the conventional fluorescent tube lamp (FTL) by energy efficient compact fluorescent lamp (CFL). Installation of false ceiling, wall insulation, different glazing types and lighting systems are cost effective with normalized annual saving ranging from 17% to 19.8% from this retrofitting project. Furthermore, the study also highlights the potential of reducing the emission of CO2 and equivalent carbon credit. Retrofitting techniques strongly influence the level of energy saving, although the payback period is generally quite long of order 8years. [Copyright &y& Elsevier]

Abstract: This paper deals with an experimental outdoor annual performance evaluation of 2.32kWP photovoltaic (PV) power system located at solar energy park in New Delhi composite climatic conditions. This PV system operates the daily electrical load nearly 10kWh/day which comprises of various applications such as electric air blower of an earth to air heat exchanger (EAHE) used for heating/cooling of adobe house, ceiling fan, fluorescent tube-light, computer, submersible water pump, etc. The outdoor efficiencies, power generated and lost in PV system components were determined using hourly experimental measured data for 1year on typical clear day in each month. These realistic data are useful for design engineers for outdoor assessment of PV system components. The energy conservation, mitigation of CO2 emission and carbon credit potential of the existing PV integrated EAHE system is presented in this paper. Also, the energy payback time (EPBT) and unit cost of electricity were determined for both stand-alone PV (SAPV) and building roof integrated PV (BIPV) systems. [Copyright &y& Elsevier]

Thermal performance of Earth Air Tunnel Heat Exchanger (EATHE) system is found to be highly dependent on thermal properties of soil and soil with poor thermal properties require longer buried pipe for desired heat exchange between air and sub-soil. In densely populated country like India, EATHE systems are rarely used due to the limited ground space (higher aspect ratio in terms of length) in most of the residential and commercial applications. Therefore, in this paper, problem of space limitation for the installation of straight EATHE system is attempted by proposing new spiral shaped EATHE system. The developed EATHE systems were used to determine cooling and heating potential individually and COP were 5.94 and 6.24 in summer; 1.92 and 2.11 in winter for straight and spiral respectively. A transient numerical model has been developed to investigate the performance of both systems. The COP were 4.23 and 4.48 in summer; 5.0 and 5.16 in winter for straight and spiral respectively. The experimental and numerical results suggested that the thermal performance of these two systems are comparable can be interchanged based on available site conditions. [ABSTRACT FROM AUTHOR]

Climate models predict an intensification of precipitation extremes as a result of a warmer and moister atmosphere at the rate of 7 % K -1. However, observations in tropical regions show contrastingly negative precipitation–temperature scaling at temperatures above 23–25 ∘ C. We use observations from India and show that this negative scaling can be explained by the radiative effects of clouds on surface temperatures. Cloud radiative cooling during precipitation events make observed temperatures covary with precipitation, with wetter periods and heavier precipitation having a stronger cooling effect. We remove this confounding effect of clouds from temperatures using a surface energy balance approach constrained by thermodynamics. We then find a diametric change in precipitation scaling with rates becoming positive and coming closer to the Clausius–Clapeyron (CC) scaling rate (7 % K -1). Our findings imply that the intensification of precipitation extremes with warmer temperatures expected with global warming is consistent with observations from tropical regions when the radiative effect of clouds on surface temperatures and the resulting covariation with precipitation is accounted for. [ABSTRACT FROM AUTHOR]

Abstract: In the past two decades, ground source heat pump (GSHP) system has made good impact on energy saving in the Western and European countries in heating/cooling and industrial applications. Their potential for reduction in CO2 emission has been very well utilized by these countries to contribute to a green environment. In this paper an attempt is made to give an overview about how India can benefit from this technology. The economic growth of India has huge impact on energy and environment of the country. Though Indian building sector is growing in multifold, still there is a demand for electricity to meet the needs of people. Any technology to reduce energy consumption will have great impact on people's life and economy. In this way a study has been carried out to estimate, to what extend the ground source heat pump technology can help India to reduce its energy demand and also save the environment. This study covers 10 provinces of northern part of India which require both heating and cooling. Based on the topography of the states, they are classified into severe winter states and moderate winter states for heating requirement. During winter period the conventional electric heaters consume electricity between 1416 and 7085GW annually and for the same heating load GSHP consumes only 471–1416GW. In summer months the electricity consumed by conventional air conditioner ranges between 5506 and 27,532GW and by GSHP it varies from 4811 to 14,440GW. The annual CO2 emission by the conventional systems used for heating and cooling vary between 5270 and 26,352millionkg of CO2. In the case of GSHP CO2 emission lies between 4022 and 12,071millionkg. It is estimated that by employing GSHP technology India can save annually a minimum electricity of 1639–18,700GW and CO2 emission of 1.3–14.2 million tons. [Copyright &y& Elsevier]

Abstract: This is the property of earth that at a depth of about 1.5 to 2m, the temperature of ground remains almost constant throughout the year. This constant temperature is called earth’s undisturbed temperature which remains higher than surface temperature of earth in winter season and vice versa in summer. For effective utilization of heat capacity of earth, the earth–air heat exchanger (EAHE) has to be designed. The EAHEs are considered as an effective passive heating/cooling medium for buildings. This is basically a series of metallic, plastic or concrete pipes buried underground at a particular depth through which the fresh atmospheric air flows and gets heated in winter and supplied to the building if at sufficiently high temperature and vice versa in summer. Till date many researchers have carried out a number of studies in designing, modeling and testing of EAHEs systems. This paper reviews on the experimental and analytical studies of EAHE systems around the world but the studies are mainly focused on EAHE systems at the Indian universities as of the end June, 2012. [Copyright &y& Elsevier]

Abstract: This paper presents the results of ship cruise and land observations of columnar aerosol characteristics over the Arabian Sea (AS) and at an in-land urban station Pune, in the western part of India, during the pre-monsoon 2006. Aerosol loading is found to decrease significantly from Pune and west coast of India to far away from the Indian west coast over AS. Relative dominance of coarse-mode particles is observed over pristine oceans, while dominance of fine-mode aerosols is noticed under certain occasions. Curvature of multi-spectral AOT variations is also found to be larger over Far AS (FAS) and Mid AS (MAS) regions, where the aerosol loading seems to be very low, compared to that over Coastal AS (CAS) region. Predominance of coarse- and fine-mode aerosols is found over Northern AS (NAS) and Southern AS (SAS) regions, respectively, along the meridional direction of AS. Surface radiative cooling due to aerosols is found to be more intense over CAS and NAS regions. It is shown that the combination of Angstrom exponent (α) and its second order (α′) could delineate aerosol type and loading. [Copyright &y& Elsevier]

The present paper presents the simulation of a solar powered absorption cooling system with an absorption working pair of lithium bromide and water. The system consists of a flat plate solar collector, a lithium bromide water absorption chiller, an auxiliary energy source and a hot water storage tank. Initially, the thermodynamic behaviour of the cooling system cycle is simulated under various ambient conditions to determine the working conditions of the absorption cooling system compatible with the capacity of the flat plate collector. Computer modelling of a solar absorption cooling system using a flat plate collector was undertaken for all possible climatic conditions of Bahal, India. The results have shown that for each ton of refrigeration a minimum collector area of 26·02 m2 with an optimal water storage tank capacity ranging from 1000 to 1500 L is required, so that the system can operate solely on solar energy for ∼7 h a day. [ABSTRACT FROM AUTHOR]

Electric power demand is growing at an exponential rate due to establishment of industries and economic growth in the country. Central electricity authority of India (CEA) has estimated per capita electricity consumption will increase at a rate of 6 percent per annum, this will increase the load on the transmission and distribution system. Limitations of Right of Way (ROW) has made it difficult to construct new lines, particularly in metropolitan and densely populated cities, hence high temperature low sag (HTLS) conductors are being used adopted, several projects in the country are being executed to overcome the problem of burdening of transmission/distribution system. HTLS conductors operate at 2–3 times higher ampacity and thermal rating, hence can be used for higher power transmission without upgrading the existing towers and infrastructure. The present investigation aims to understand and estimate the conductor temperature and ampacity dependent on different parameters like wind velocity, wind angle, emissivity and fault current level. The investigation highlights the dynamic thermal rating of HTLS conductor with change in wind velocity and angle, thermal performance of conductor during fault condition and thermal rating with emissivity, absorptivity and ambient temperature during flow of fault current is presented. A new experimental setup is established to investigate the performance of HTLS and Traction copper conductor in the laboratory, attempt has been made to study effect of magnetic fields and conduct EBSD analysis, some important conclusions drawn from the investigations are analyzed and presented. [ABSTRACT FROM AUTHOR]

Determination of the peak thermal condition is vital in order to understand tectono-thermal evolution of the Himalayan belt. The Lesser Himalayan Sequence (LHS) in the Western Arunachal Pradesh, being rich in carbonaceous material (CM), facilitates the determination of peak metamorphic temperature based on Raman spectroscopy of carbonaceous material (RSCM). In this study, we have used RSCM method of Beyssac et al. (J Metamorph Geol 20:859-871, ) and Rahl et al. (Earth Planet Sci Lett 240:339-354, ) to estimate the thermal history of LHS and Siwalik foreland from the western Arunachal Pradesh. The study indicates that the temperature of 700-800 °C in the Greater Himalayan Sequence (GHS) decreases to 650-700 °C in the main central thrust zone (MCTZ) and decreases further to <200 °C in the Mio-Pliocene sequence of Siwaliks. The work demonstrates greater reliability of Rahl et al.'s (Earth Planet Sci Lett 240:339-354, ) RSCM method for temperatures >600 and <340 °C. We show that the higher and lower zones of Bomdila Gneiss (BG) experienced temperature of ~600 °C and exhumed at different stages along the Bomdila Thrust (BT) and Upper Main Boundary Thrust (U.MBT). Pyrolysis analysis of the CM together with the Fission Track ages from upper Siwaliks corroborates the RSCM thermometry estimate of ~240 °C. The results indicate that the Permian sequence north of Lower MBT was deposited at greater depths (>12 km) than the upper Siwalik sediments to its south at depths <8 km before they were exhumed. The Ar/Ar ages suggest that the upper zones of Se La evolved ~13-15 Ma. The middle zone exhumed at ~11 Ma and lower zone close to ~8 Ma indicating erosional unroofing of the MCT sheet. The footwall of MCTZ cooled between 6 and 8 Ma. Analyses of P- T path imply that LHS between MCT and U.MBT zone falls within the kyanite stability field with near isobaric condition. At higher structural level, the temperatures increase gradually with P- T conditions in the sillimanite stability field. The near isothermal (700-800 °C) condition in the GHS, isobaric condition in the MCTZ together with T- t path evidence of GHS that experienced relatively longer duration of near peak temperatures and rapid cooling towards MCTZ, compares the evolution of GHS and inverted metamorphic gradient closely to channel flow predictions. [ABSTRACT FROM AUTHOR]

Green roof is a passive cooling technique that stops incoming solar radiation from reaching the building structure below. Many studies have been conducted over the past 10 years to consider the potential building energy benefits of green roofs and have shown that they can offer benefits in energy reduction for winter heating as well as summer cooling. Green roofs have many benefits over conventional roofs: they reduce storm water run-off, the heat island effect in cities and energy requirements for cooling; all of this while sequestering some CO2 from the atmosphere. But because of their expense, the building industry has yet to fully embrace their large-scale implementation. Over the summer', two test structures, one with a green roof and the other with an RCC roof, were built and tested at the Ujjain Engineering College, Ujjain, RGPV University, to determine their cooling potential. Results indicate that the test cell with the green roof consistently performs better than those with the conventional cement RCC roof. [ABSTRACT FROM AUTHOR]

Trials in developed countries have shown that therapeutic hypothermia reduces the risk of death or severe disability in infants with neonatal encephalopathy. Cooling has been adopted as a standard of care in some parts of the world. Some Indian neonatal units have considered or even embarked upon cooling encephalopathic term newborn infants. In this article we discuss some of the potential ethical questions that should be considered before introducing therapeutic hypothermia in an Indian setting. Eviden ce from previous trials may not be relevant given significant differences in the epidemiology of neonatal encephalopathy in countries like India. There is a possibility that hypothermia would be ineffective or harmful. The most appropriate way to answer these concerns would be to perform a large randomized controlled trial of cooling in India. However, such trials will also raise potential ethical challenges. Cooling may also affect decisions about treatment withdrawal, and may create uncertainty about prognosis. It may exacerbate ethical problems relating to lack of neonatal intensive care bed space. [ABSTRACT FROM AUTHOR]