19,683 research outputs found
Technology portfolio analysis for residential lighting
electricity forces the electricity utilities to increase their generating capacity. The huge investments on generation, transmission and distribution (at the cost of alternative development projects) adversely affect India's scarce capital resources. Also, internal energy resources like coal are utilised with a great risk to the environment. This paper attempts to show analytically the benefits of shift in the focus from supply augmentation to demand management through a case study of replacement of inefficient devices with efficient ones for residential lighting. This is being done by analyzing the economics of various alternatives and developing an optimal portfolio for meeting the lighting requirement of a typical household in Maharashtra State in India. A mixed integer-programming model has been used for developing the optimal portfolio and a comparison of annual returns is made. Finally, the results for the typical household have been extended to the state of Maharashtra and the cost and benefits are estimated. The results show that the optimal lighting portfolio provides a far higher return at a lower risk compared to other investment alternatives like the stock market while providing substantial savings both in terms of energy and peak demand.Demand management, electricity consumption, energy resources, mixed integer-programming model, rate of return
Hydrogen Energy For Indian Transport Sector - A Well-To-Wheel Techno-Economic and Environmental Feasibility Analysis
With the alarming rate of growth in vehicle population and travel demand, the energy consumption has increased significantly contributing to the rise of GHG emissions. Therefore, the development of a viable environmentally benign technology/fuel, which minimises both global and local environmental impacts, is the need of the hour. There are four interconnected reasons for propagating a shift towards alternative fuels/technologies : (i) Energy Supply : world oil reserves are rapidly diminishing, (ii) Environment : local pollution from vehicles is creating an atmosphere that is increasingly damaging public health and environment, (iii) Economic competitiveness : the cost of producing oil and regulating the by-products of oil consumption continues to increase, and (iv) Energy security : the military and political costs of maintaining energy security in international markets are becoming untenable. Hydrogen energy has been demonstrated as a viable alternative automotive fuel in three technological modes : internal combustion engines connected mechanically to conventional vehicles; fuel cells that produce electricity to power electric vehicles; and hybrids that involve combinations of engines or fuel cells with electrical storage systems, such as batteries The present study provides a well-to-wheel analysis of the economic and environmental implications of technologies to deliver the hydrogen energy to the vehicles. The main objectives of the study are : (i) prioritization of technologies of hydrogen production, transportation, storage and refueling, (ii) economic analysis of prioritized technology alternatives to estimate the delivered cost of hydrogen at the end-use point, and (iii) estimating the environmental impacts. To achieve the desired objectives, various quantitative life-cycle-cost analyses have been carried out for numerous pathways (i.e. technologies and processes) for hydrogen production, storage, transportation/distribution and dispensing. The total cost implications are arrived at by combining the costs of hydrogen (at end-use point) and the estimated demand for hydrogen for transport. The environmental benefits (potential to abate GHG emissions) of alternative hydrogen energy technology pathways have been worked out by using the standard emission factors. Finally, the GHG emission levels of hydrogen supply pathways are compared with those of diesel and petrol pathways. The application of this systematic methodology will simulate a realistic decision-making process.Hydrogen Energy, Indian Transport Sector, Feasibility Analysis
Commercialisation of Sustainable Energy Technologies
Commercialization efforts to diffuse sustainable energy technologies (SETs) need to be sustainable in terms of replication, spread and longevity, and should promote goal of sustainable development. Limited success of diffusion through government driven pathways illustrates the need for market-based approaches to SET commercialization. This paper presents a detailed treatment of the pre-requisites for adopting a private sector driven business model approach for successful diffusion of SETs. This is expected to integrate the processes of market transformation and entrepreneurship development with innovative regulatory, marketing, financing, incentive and intermediary mechanisms. Further, it envisages a public-private partnership driven-mechanism as a framework for diffusion leading to technology commercialization.Commercialisation, Energy, Financing, technology, Sustainable
Technology portfolio analysis for residential lighting
Electricity consumption in India is increasing rapidly over the years. The increased demand for electricity forces the electricity utilities to increase their generating capacity. The huge investments on generation, transmission and distribution (at the cost of alternative development projects) adversely affect India's scarce capital resources. Also, internal energy resources like coal are utilised with a great risk to the environment. This paper attempts to show analytically the benefits of shift in the focus from supply augmentation to demand management through a case study of replacement of inefficient devices with efficient ones for residential lighting. This is being done by analyzing the economics of various alternatives and developing an optimal portfolio for meeting the lighting requirement of a typical household in Maharashtra State in India. A mixed integer-programming model has been used for developing the optimal portfolio and a comparison of annual returns is made. Finally, the results for the typical household have been extended to the state of Maharashtra and the cost and benefits are estimated. The results show that the optimal lighting portfolio provides a far higher return at a lower risk compared to other investment alternatives like the stock market while providing substantial savings both in terms of energy and peak demand.Demand management, electricity consumption, energy resources, mixed integer-programming model, rate of return
Hydrogen energy for Indian transport sector: A Well-to-wheel techno-economic and environmental feasibility analysis
With the alarming rate of growth in vehicle population and travel demand, the energy consumption has increased significantly contributing to the rise of GHG emissions. Therefore, the development of a viable environmentally benign technology/fuel, which minimises both global and local environmental impacts, is the need of the hour. There are four interconnected reasons for propagating a shift towards alternative fuels/technologies: (i) Energy Supply: world oil reserves are rapidly diminishing, (ii) Environment: local pollution from vehicles is creating an atmosphere that is increasingly damaging public health and environment, (iii) Economic competitiveness: the cost of producing oil and regulating the by-products of oil consumption continues to increase, and (iv) Energy security: the military and political costs of maintaining energy security in international markets are becoming untenable. Hydrogen energy has been demonstrated as a viable alternative automotive fuel in three technological modes: internal combustion engines connected mechanically to conventional vehicles; fuel cells that produce electricity to power electric vehicles; and hybrids that involve combinations of engines or fuel cells with electrical storage systems, such as batteries The present study provides a well-to-wheel analysis of the economic and environmental implications of technologies to deliver the hydrogen energy to the vehicles. The main objectives of the study are: (i) prioritization of technologies of hydrogen production, transportation, storage and refueling, (ii) economic analysis of prioritized technology alternatives to estimate the delivered cost of hydrogen at the end-use point, and (iii) estimating the environmental impacts. To achieve the desired objectives, various quantitative life-cycle-cost analyses have been carried out for numerous pathways (i.e. technologies and processes) for hydrogen production, storage, transportation/distribution and dispensing. The total cost implications are arrived at by combining the costs of hydrogen (at end-use point) and the estimated demand for hydrogen for transport. The environmental benefits (potential to abate GHG emissions) of alternative hydrogen energy technology pathways have been worked out by using the standard emission factors. Finally, the GHG emission levels of hydrogen supply pathways are compared with those of diesel and petrol pathways. The application of this systematic methodology will simulate a realistic decision-making process.
A Note On Line Graphs
In this note we define two generalizations of the line graph and obtain some
results. Also, we mark some open problems
Superconductivity in doped FeTe1-xSx (x= 0.00 to 0.25) single crystals
We report self flux growth and characterization of FeTe1-xSx (x= 0.00 to
0.25) single crystal series. Surface X-ray diffraction (XRD) exhibited
crystalline nature with growth in (00l) plane. Micro-structural (electron
microscopy) images of representative crystals showed the slab-like morphology
and near stoichiometric composition. Powder XRD analysis (Rietveld) of single
crystals exhibited tetragonal structure with P4/nmm space group and decreasing
a and c lattice parameters with increase in x. Electrical resistivity
measurements (R-T) showed superconductivity with Tconset at 9.5K and 8.5K for x
=0.10 and x =0.25 respectively. The un-doped crystal exhibited known step like
anomaly at around 70K. Upper critical field Hc2(0), as calculated from magneto
transport for x =0.25 crystal is around 60Tesla and 45Tesla in H//ab and H//c
directions. Thermal activation energy [U0(H)] calculated for x =0.10 and 0.25
crystals followed weak power law, indicating single vortex pinning at low
fields. Mossbauer spectra for FeTe1-xSx crystals at 300K and 5K are compared
with non superconducting FeTe. Both quadrupole splitting (QS) and isomer shift
(IS) for S doped crystals were found to decrease. Also at 5K the hyperfine
field for x =0.10 superconducting crystal is decreased substantially from
10.6Tesla (FeTe) to 7.2Tesla. For x =0.25 crystal, though small quantity of
un-reacted Fe is visible at room temperature, but unlike x =0.10, the low
temperature (5K) ordered FeTe hyperfine field is nearly zero.Comment: 20 Pages Text + Figs: Accepted Mat. Res. Exp, Mat. Rex. Exp. (2018
The Stability of Non Newtonian Fluid Between the Two Rotating Porous Cylinders (Wide Gap Case)
This paper is primarily concerned with the stability of the non Newtonian fluid between two porous cylinders in the case of wide gap. The problem is discussed for Mhu>0,Mhu=0 and Mhu,0. The results show that the Taylor number depends on the gap size in the case of non Newtonian fluids and the presence of suction stabilizes the flow whereas the injection destabilizes the flow. Its is found the stability of the fluid decreases when the gap increases. The non Newtonian fluid is less stable when compared to the Newtonian fluid in the case of wide gap. It is also found in the case of wide gap(for non Newtonian fluid and the cylinders are counter rotating equally) the application of injection at the outer cylinder disturbs the radial velocity will not effect any appreciable change or disturbance in the vortex cell pattern at the onset of instability
Stability of a Non Newtonian Fluid Between Two Concentric Rotating Porous Cylinders
The stability of non-Newtonian fluid confined between two concentric rotating porous cylinders has been examined. The critical determines the on set of instability has been determined as a function of 'a' (wave length) and S (cross viscous parameter). The variation of the critical Taylor number with S, suction parameter lambda and radial velocity distribution have been shown. It has been found that the effect of suction at the outer cylinder is to stabilize the flow whereas the injection destabilizes the flow. The presence of suction or injection does not affect radial velocity curves or vortex cells
- âŚ