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Roy R.,Bengal Engineering and Science University | Ghosh D.,Lahmeyer International India Pvt. Ltd | Bhattacharya G.,Bengal Engineering and Science University
Landslides | Year: 2015

Landslides triggered by moderate to major earthquakes are a recognized seismic hazard. Arias Intensity (Ia) is a key intensity measure of the ground motion, but significant duration is widely used to define strong motion duration. We calculate Newmark’s displacements using earthquake records bracketing a broad range of Arias Intensity and significant duration employing Newmark’s rigid block method and a number of yield accelerations. Total landslide displacement increases with the increase in the energy content of the ground motion (Ia) above a threshold. Such threshold may be expressed as a function of yield acceleration of the slope regardless of the ground motion characteristics. Newmark displacement decreases with increasing duration for earthquakes with similar energy content. The wide scatter in the results converges when using formal dimensional analysis. Self-similar symmetry may facilitate the assessment of the performance of slopes during earthquakes. The mathematical framework for probabilistic determination of landslides displacement may be a useful aid to estimate the likelihood of landslide hazards provided that the geotechnical properties of the slopes are known. © 2015 Springer-Verlag Berlin Heidelberg


Narayanan P.,TERI University | Basistha A.,Lahmeyer International India Pvt. Ltd | Sachdeva K.,TERI University
Weather | Year: 2016

The spatial and temporal variability of rainfall patterns in the northwestern belt of India has been monitored over a period of 60 years (1949–2009). The trends and shifts in the data have been calculated using the Modified Mann-Kendall test (MMK) and the Pettitt-Mann-Whitney test (PMW), respectively. To explain the shifts in rainfall at different stations in the northwestern region, the dominant climate indices were analysed for pre- and post-shift years. The climate indices and rainfall distribution data were subjected to Principal Component Analysis (PCA) in order to understand the nature of rainfall distribution and the dominant indices related to its variability. The analysis of PCA results with respect to season shows that each station is influenced by one or more climatic factors; however, these factors are themselves influenced by other important atmospheric phenomena, such as western disturbances. The preliminary principle component analysis of rainfall data with respect to climatic indices indicates that Niño 3.4 and Pacific Decadal Oscillation (PDO) are the dominant climatic indices that have caused a shift in the rainfall pattern of western India, along with land use/land cover changes. © 2016 Royal Meteorological Society


Purohit I.,Lahmeyer International India Pvt. Ltd. | Purohit P.,International Institute For Applied Systems Analysis
Renewable and Sustainable Energy Reviews | Year: 2015

Solar radiation resource assessment is one of the most important exercises towards implementation of large-scale solar power projects. The quality of resource makes significant impact on the selection of technology to be used at a specific location for solar electricity generation. In this study, inter-comparability of several solar radiation databases (i.e. ground, satellite and statistical) is assessed in Indian context. The long-term measured Global Horizontal Irradiance (GHI) over 23 representative locations is compared with the GHI obtained from satellite and weather databases. Direct Normal Irradiance (DNI) is estimated through long-term measured global horizontal and diffuse irradiance using basic sun-earth geometry and compared with the DNI obtained from different solar radiation and weather databases. It is observed that with respect to long-term measured data of GHI the average range of deviation varied from 0.20% to 22.53% whereas DNI varied from 0.64% to 35.12% across select locations. Impact of the variation due to solar radiation resource assessment on the annual electricity generation and levelized cost of electricity of grid-connected solar power projects is also underlined. © 2015 Elsevier Ltd. All rights reserved.


Narayanan P.,TERI University | Basistha A.,Lahmeyer International India Pvt. Ltd | Sarkar S.,TERI University | Kamna S.,TERI University
Comptes Rendus - Geoscience | Year: 2013

Spatial and temporal variability of rainfall over different seasons influence physical, social and economic parameters. Pre-monsoon (March, April and May - MAM) rainfall over the country is highly variable. Since heat lows and convective rainfall in MAM have an impact on the intensity of the ensuing monsoons, hence the pre-monsoon period was chosen for the study. The pre-whitened Mann Kendall test was used to explore presence of rainfall trend during MAM. The results indicate presence of significant (at 10% level) increasing trend in two stations (Ajmer, Bikaner). The practical significance of the change in rainfall was also explored as percentage changes over long term mean, using Theil and Sen's median slope estimator. Forecast using univariate ARIMA model for pre-monsoon months indicates that there is a significant rise in the pre-monsoon rainfall over the northwest part of the country. © 2013.


Jha A.K.,Lahmeyer International India Pvt. Ltd
Water and Energy International | Year: 2014

Indian Economy is in a critical need for electric power to achieve its cherished goal of faster growth. Hydropower is a critical element in meeting the power need of the economy. The Government has created policies, framework and institutions for a rapid harnessing of the hydropower potential of the country. The private sector too has responded overwhelmingly to this effort by the Government. In spite of all these, hydropower development in India has been slow and marred by teething problems. The sector today appears almost at a crossroad. The problem for this state of things ranges from technical to the contractual to the socio environmental. These have been analysed and presented herein with the perspective of a consultant. © Central Board of Irrigation and Power. All rights reserved.


Purohit I.,Lahmeyer International India Pvt. Ltd. | Purohit P.,International Institute For Applied Systems Analysis | Shekhar S.,TERI University
Energy Policy | Year: 2013

To accelerate the decarburization in the Indian power sector, concentrating solar power (CSP) needs to play an important role. CSP technologies have found significant space in the Jawaharlal Nehru National Solar Mission (JNNSM) of the Indian government in which 20,000. MW grid connected solar power projects have been targeted by 2022 with 50% capacity for CSP. In this study a preliminary attempt has been made to assess the potential of CSP generation in the Northwestern (NW) regions of India; which seems a high potential area as it has the highest annual solar radiation in India, favorable meteorological conditions for CSP and large amount of waste land. The potential of CSP systems in NW India is estimated on the basis of a detailed solar radiation and land resource assessment. The energy yield exercise has been carried out for the representative locations using System Advisor Model for four commercially available CSP technologies namely Parabolic Trough Collector (PTC), Central receiver system (CRS), Linear Fresnel Reflector (LFR) and Parabolic Dish System (PDS). The financial viability of CSP systems at different locations in NW India is also analyzed in this study. On the basis of a detailed solar radiation and land resource assessment, the maximum theoretical potential of CSP in NW India is estimated over 2000GW taking into accounts the viability of different CSP technologies and land suitability criteria. The technical potential is estimated over 1700GW at an annual direct normal incidence (DNI) over 1800kWh/m2 and finally, the economic potential is estimated over 700GW at an annual DNI over 2000kWh/m2 in NW India. It is expected that in near future locations with lower DNI values could also become financially feasible with the development of new technologies, advancement of materials, economy of scale, manufacturing capability along with the enhanced policy measures etc. With an annual DNI over 1600kWh/m2 it is possible to exploit over 2000GW CSP in the NW India. © 2013 Elsevier Ltd.

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