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1.
An analysis of the effects of providing a single adjustable mirror booster, hinged on a box type solar cooker, is made. The mirror is hinged on one side and points toward the south. The total energy falling on the cooker aperture is calculated for a latitude of 18°N (Warangal City) and for five different declinations of the sun (five different days in a year). The effects of mirror adjustment are analysed under three categories to determine the energy boost. The calculations clearly demonstrate the choice among intermittent adjustment, continuous adjustment and fixed orientation of the mirror. Only beam radiation is considered in the calculations.  相似文献   

2.
Energy supplies particularly in remote and far-flung rural areas are in pathetic situation. Leave aside other needs, most of the rural communities still use wood as a source of energy for cooking. Burning of wood is not only an inefficient method, but also hazardousness for the person working on the stove. People have been working for cleaner and efficient means of cooking for decades. Solar cooker- and biogas-based cook stoves are two of the successfully implemented technologies in this area. Although solar cooker requires no maintenance, the initial investment is quite high for a cluster of villages. In addition to this, the intermittency involved in solar energy makes this an unreliable source.

In this paper, a cluster of villages of Narendra Nagar block of Tehri Garhwal district of Uttarakhand, India, has been studied in terms of their thermal requirements. The potential of solar energy and biomass energy has been estimated. An integrated solar–biogas system has been proposed to satisfy this cooking demand. To obtain the optimal sizes of solar cooker and biogas generator, MATLAB codes have been developed. It was found that this system is more economical and much reliable than the other two cases.  相似文献   


3.
Small scale, decentralised electricity generation at village level, based on locally available biomass, is a promising solution for providing electricity access in remote rural areas, as it can supply villages with an independent, reliable, high quality and environmentally friendly energy source. However, despite such systems′ technological feasibility, they are often discontinued. Research so far has not studied the reasons for discontinuation. This article analyses a case of biomass based gasification in India, by studying the type of goods the village system provides, and the distribution of benefits within the system. In this case, the infrastructural and social system provide electricity as a “club good”. Given fluctuating numbers of service users, the club faced the decision to either expand the system to new members, or to reduce the services provided. The focus on the village community hampered the extension of “the club”. A reduction in the quality and quantity of services however decreased the comfort provided by the system. The system faced what here is called a “club dilemma”. To avoid the “club dilemma” and for a sustained energy provision, policy needs to find means to secure feedstock, i.e. by the means of subsidies or collaboration with agricultural departments.  相似文献   

4.
Karnataka has been among the most successful markets for solar lighting systems (SLS) among Indian states. In order to understand the dynamics of systems adoption and operation, that have fostered market based adoption of solar lighting, we interviewed rural households from six districts that had purchased solar lighting systems using loans at market rates, the rural banks that provided loans and the solar firms that marketed the technology. We found that a large proportion of households in our sample were connected to the grid but chose to install solar lighting because they considered the power supply from the grid to be unreliable. Households in our sample reported savings on electricity costs and reduced kerosene usage for lighting. In addition to providing credit, banks also play a key role in ensuring good service and maintenance; the viability of the SLS market is thus critically dependent on the role that the banks play as intermediaries between consumers and solar firms in rural areas. Government programs should be carefully designed to match the incentives of firms, banks and consumers if the successes of the ‘Karnataka model’ are to be repeated and amplified.  相似文献   

5.
India′s energy situation is characterized by increasing energy demand, high fossil fuel dependency, large import shares, and significant portion of population deprived of modern energy services. At this juncture, natural gas, being the cleanest fossil fuel with high efficiency and cost effectiveness, is expected to play an important role. India, with only 0.6% of proven world reserves, is not endowed with adequate natural gas domestically. Nevertheless, there are gas reserves in neighbouring regions which gives rise to the prospects of three cross border gas pipeline projects, namely, Iran–Pakistan–India, Turkmenistan–Afghanistan–Pakistan–India, and Myanmar–Bangladesh–India. This study is a political analysis of these pipeline projects. First, it provides justification on use of natural gas and promotion of cross border energy trade. Then it examines these three pipeline projects and analyses the security concerns, role of different actors, their positions, shifting goals, and strategies. The study develops scenarios on the basis of changing circumstances and discusses some of the pertinent issues like technology options for underground/underwater pipelines and role of private players. It also explores impact of India′s broader foreign relations and role of SAARC on the future of pipelines and proposes energy induced mutually assured protection (MAP) as a concept for regional security.  相似文献   

6.
Biomass is a renewable energy source that is routinely used for cooking in the developing world, especially in rural areas. The World Health Organization estimates that about 2.5 billion people globally rely on biomass, such as wood, agricultural waste and animal dung to meet their energy needs for cooking utilising traditional low-efficiency cookstoves. However, certain human health risks are associated with the inhalation of off-gases resulting from the indoor use of biomass for cooking, especially for women and children who spend more of their time at home. On the other hand, use of energy-efficient cookstoves is considered to reduce those risks. Thus, qualitative and quantitative measurements of cookstove performance are necessary in order to make different stoves and different cooking processes comparable. The aim of this paper is the presentation of the current situation regarding biomass use for cooking with emphasis placed on the developing world, the brief of the adverse health impacts of biomass burning based on the review of literature, the presentation of the merits of improved efficiency cookstoves and to highlight the need for stove performance tests. The demand of different types of biomass is not likely to change in the near future in the developing world since biomass is readily available and cheap. Thus, the efforts to improve household air quality must concentrate on improving cookstoves efficiency and ventilation of the flue gases outdoors. Programmes for the improvement of the cookstoves efficiency in the developing world should be part of the development agenda.  相似文献   

7.
8.
The angular-dependent optical properties of low-e and solar control glazings have been investigated in a European project, ADOPT, within the Standards Measurements and Testing programme. The object of the project has been to identify reliable ways of predicting the angular dependency without having to perform measurements or detailed calculations. Two new predictive algorithms have been developed and validated. For the investigated coatings the accuracy of these predictive algorithms is mostly within 1% of the value obtained by measurements or Fresnel calculations. This is an improvement over previously used algorithms, which have failed to distinguish between different types of coatings. The improved accuracy is of importance in energy simulation of buildings and makes improved product specification possible.  相似文献   

9.
The increasing awareness of the depletion of fossil fuel resources and the environmental benefits of biodiesel fuel has made it more attractive in recent times. The cost of biodiesel, however, is the major hurdle to its commercialization in comparison to petroleum-based diesel fuel. The high cost is primarily due to the raw material, mostly neat vegetable oil. Used cooking oil is one of the economical sources for biodiesel production. However, the products formed during frying, can affect the transesterification reaction and the biodiesel properties. This paper attempts to review various technological methods of biodiesel production from used cooking oil. The analytical methods for high quality biodiesel fuel from used cooking oil like GC, TLC, HPLC, GPC and TGA have also been summarized in this paper. In addition, the specifications provided by different countries are presented. The fuel properties of biodiesel fuel from used cooking oil were also reviewed and compared with those of conventional diesel fuel.  相似文献   

10.
Overreliance on biomass energy, such as firewood and charcoal, for cooking in developing countries has contributed to high rates of deforestation and resulted in substantial indoor pollution, which has negatively impacted the health of many individuals. However, the effectiveness of public policies aimed at encouraging households to switch to cleaner fuels, such as liquefied petroleum gas (LPG) and kerosene, hinges on the extent to which they are mentally committed to specific fuels. Using data on four cooking fuels (charcoal, firewood, LPG, and kerosene) from the Ghana living standards survey, we found strong evidence that the most preferred fuel is LPG, followed by charcoal, with kerosene the least preferred. In addition, with the exception of kerosene that has price-elastic demand, the price elasticities of demand for the fuel types examined are inelastic. This finding suggests the so-called fuel-ladder is not robust.  相似文献   

11.
India is trying hard to improve the standard of living of its peoples, and therefore increase the energy consumption. Amongst the many options. India is also researching the various aspects of the hydrogen energy system. This paper presents an overview of hydrogen energy research and development work in India, starting with a summary of the energy situation in the country.  相似文献   

12.
In the present scenario, all over the world, electrical energy is produced by conventional or non-renewable energy supply system. These systems produce a large amount of atmospheric pollution. This predicament is principally conquered by the concentrated use of alternative or renewable energy system. The research work reported in the paper shows the profoundness of performance prediction and investigation of solar–tidal integrated renewable energy system using a different optimisation technique. The works on macro-level include a novel tidal–solar system in the coastal area of Cochin, India and modelling of tidal-solar energy system by the HOMER software. Duration of the project is assessed by a project management technique critical path method, optimisation of the HOMER software cost assessment result for the study area using teaching, learning-based optimisation, cuckoo optimisation and through the grasshopper technique, further reliability and life-cycle analysis of the system and result are validated by regression analysis.  相似文献   

13.
Solar catalytic decomposition of methane (SCDM) was investigated in a solar furnace facility with different catalysts. The aim of this exploratory study was to investigate the potential of the catalytic methane decomposition approach providing the reaction heat via solar energy at different experimental conditions. All experiments conducted pointed out to the simultaneous production of a gas phase composed only by hydrogen and un-reacted methane with a solid product deposited into the catalyst particles varying upon the catalysts used: nanostructured carbons either in form of carbon nanofibers (CNF) or multi-walled carbon nanotubes (MWCNT) were obtained with the metallic catalyst whereas amorphous carbon was produced using a carbonaceous catalyst. The use of catalysts in the solar assisted methane decomposition present some advantages as compared to the high temperature non-catalytic solar methane decomposition route, mainly derived from the use of lower temperatures (600–950 °C): SCDM yields higher reaction rates, provides an enhancement in process efficiency, avoids the formation of other hydrocarbons (100% selectivity to H2) and increases the quality of the carbonaceous product obtained, when compared to the non-catalytic route.  相似文献   

14.
Dissemination programs of nontraditional cookstoves often fail. Nontraditional cookstoves aim to solve problems associated with biomass fuel usage in developing countries. Recent studies do not explain what drives user's cookstove choice. This study therefore builds a holistic framework that centralizes product-specific preferences or needs. The case study identifies product-specific factors that influence rural Senegalese inhabitants to switch to solar cooking, using best–worst scaling. Looking at the preferences, the case study classified 126 respondents, in three distinct market segments with different solar cooking expectations. The paper identifies socio-demographic characteristics that explain these differences in the respondents' preferences. Finally, the respondent sample is divided in two groups: solar cooker owners and non-owners. When studied with regard to the same issue, solar cooker owners appear to value benefits of the solar cooker lower than non-owners. This is due to program factors (such as formations, after-sales network) and miscommunication (such as a wrong image of the solar cooker) that highly influenced the respondents' cookstove choice. As a conclusion, solar cookers and solar cooking programs are not always adapted to the needs and requirements of the end-users. Needs-oriented and end-user adopted strategies are necessary in order to successfully implement nontraditional cookstoves programs.  相似文献   

15.
In this paper, the Arab world is surveyed initially for the availability of new and renewable energy sources (NRES) including solar energy. A classification is made based on the level of development and on the energy balance of each Arab country. The target is to utilize these NRES for hydrogen production and hence for desert development claiming more arable land. The emphasis is on using solar energy.Hydrogen will be harnessed along the following avenues: (a) to provide energy for land development, (b) to provide energy for pumping and irrigation, (c) to produce fresh water, (d) to produce fertilizers based on ammonia as a starting raw material. Case studies are presented for Egypt and Saudi Arabia.  相似文献   

16.
J.D. Nixon  P.K. Dey  P.A. Davies   《Energy》2010,35(12):5230-5240
This study of concentrating solar thermal power generation sets out to evaluate the main existing collection technologies using the framework of the Analytical Hierarchy Process (AHP). It encompasses parabolic troughs, heliostat fields, linear Fresnel reflectors, parabolic dishes, compound parabolic concentrators and linear Fresnel lenses. These technologies are compared based on technical, economic and environmental criteria. Within these three categories, numerous sub-criteria are identified; similarly sub-alternatives are considered for each technology. A literature review, thermodynamic calculations and an expert workshop have been used to arrive at quantitative and qualitative assessments. The methodology is applied principally to a case study in Gujarat in north-west India, though case studies based on the Sahara Desert, Southern Spain and California are included for comparison. A sensitivity analysis is carried out for Gujarat. The study concludes that the linear Fresnel lens with a secondary compound parabolic collector, or the parabolic dish reflector, is the preferred technology for north-west India.  相似文献   

17.
There is wide agreement in the literature that non-technical factors play a decisive role in the successful implementation of bioenergy projects. One underlying reason is that such projects require the involvement of many stakeholders, such as feedstock producers, engineers, authorities and the concerned public. We analyze the role of bioenergy-specific non-technical factors for the success of bioenergy projects. In a broad literature review we first identify potential success factors belonging to the five dimensions project characteristics, policy framework, regional integration, public perception and stakeholders. Using these factors as conceptual framework, we next analyze six Japanese pilot projects for bioenergy utilization supported by Japans Agriculture, Forestry and Fisheries Research Council. We apply Rough Set Analysis, a data mining method that can be used for small sample sizes to identify patterns in a dataset. We find that, by and large, non-technical factors from all five dimensions – such as the stability of the local policy framework – co-occur with project success. Furthermore, we show that there are diverging interpretations as to what success in a bioenergy project means. This requires tradeoffs between various goals, which should be identified and addressed explicitly at early stages of such a project.  相似文献   

18.
The technical and economic feasibility study of an innovative wind–solar hybrid renewable energy generation system with rainwater collection feature for electrical energy generation is presented in this paper. The power generated would supply part of the energy requirements of the high-rise building where the system is installed. The system integrates and optimizes several green technologies; including urban wind turbine, solar cell module and rain water collector. The design was conceptualized based on the experiences acquired during the development and testing of a suitable wind turbine for Malaysian applications. It is compact and can be built on top of high-rise buildings in order to provide on-site renewable power to the building. It overcomes the inferior aspect on the low wind speed by channeling and increasing the speed of the high altitude free-stream wind through the power-augmentation-guide-vane (PAGV) before it enters the wind turbine at the center portion. The shape or appearance of the PAGV that surrounds the wind turbine can be blended into the building architecture without negative visual impact (becomes part of the building). The design improves the starting behavior of wind turbines. It is also safer to people around and reduces noise pollution. The techno-economic analysis is carried out by applying the life cycle cost (LCC) method. The LCC method takes into consideration the complete range of costs and makes cash flows time-equivalent. The evaluations show that for a system with the PAGV (30 m diameter and 14 m high) and an H-rotor vertical axis wind turbine (17 m diameter and 9 m high) mounted on the top of a 220 m high building, the estimated annual energy savings is 195.2 MW h/year.  相似文献   

19.
This work explores public opinions regarding climate change and mitigation options and examines how psychological factors, such as attitudes, norms, and willingness to pay, determine self-reported energy-efficient behaviour. The aim is to create knowledge for the design and implementation of policy measures. The results of an opinion poll conducted in 2005 and 2010 are compared. The number of respondents favouring new technologies as a way to reduce emissions was substantially lower in 2010 than in 2005, whereas there was an increase in the number of people who acknowledged that lifestyle changes are necessary to counteract climate changes. This indicates an increased awareness among the public of the need for lifestyle changes, which could facilitate implementation of policies promoting environmental behaviour. Renewable energy and energy saving measures were ranked as the top two measures for mitigating climate change in both polls. In determining which energy behaviours of the public are determined by psychological factors, an analysis of the 2010 survey revealed that respondents with pro-environmental attitudes towards global warming favour significantly increased use of renewable energy technologies and greater engagement in energy-efficient behaviours.  相似文献   

20.
As the environment degrades at an alarming rate, there have been steady calls by most governments following international energy policies for the use of biofuels. One of the biofuels whose use is rapidly expanding is biodiesel. One of the economical sources for biodiesel production which doubles in the reduction of liquid waste and the subsequent burden of sewage treatment is used cooking oil (UCO). However, the products formed during frying, such as free fatty acid and some polymerized triglycerides, can affect the transesterification reaction and the biodiesel properties. This paper attempts to collect and analyze published works mainly in scientific journals about the engine performance, combustion and emissions characteristics of UCO biodiesel on diesel engine. Overall, the engine performance of the UCO biodiesel and its blends was only marginally poorer compared to diesel. From the standpoint of emissions, NOx emissions were slightly higher while un-burnt hydrocarbon (UBHC) emissions were lower for UCO biodiesel when compares to diesel fuel. There were no noticeable differences between UCO biodiesel and fresh oil biodiesel as their engine performances, combustion and emissions characteristics bear a close resemblance. This is probably more closely related to the oxygenated nature of biodiesel which is almost constant for every biodiesel (biodiesel has some level of oxygen bound to its chemical structure) and also to its higher viscosity and lower calorific value, which have a major bearing on spray formation and initial combustion.  相似文献   

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