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1.
The rural population of Himalaya has been strongly dependent on the forest resources for their livelihood for generations. The present study, carried out at three different altitudes of Kedarnath Wildlife Sanctuary (KWLS), explored forest resource-use patterns to understand rural peoples' dependency on the adjacent forests. A total of six forests were selected and the seven dependent villages were surveyed for the study of forest resource use patterns in relation to their socioeconomic status. Average fuelwood and fodder consumption were found to be 2.42 kg/capita/day and 43.96 kg/household/day respectively which was higher than the earlier reported values. Average fuelwood consumption by temporary dhaba (roadside refreshment establishments) owners (52.5 kg/dhaba/day) is much higher than the permanent villagers. Average cultivated land per family was less than 1 ha (0.56 ha). Inaccessibility of the area and deprived socio-economic status of the locals are largely responsible for the total dependency of the local inhabitants on nearby forests for fuelwood, fodder and other life supporting demands. Extensive farming of fuelwood trees on less used, barren land and establishment of fodder banks could be the alternative to bridge the gap between the demand and supply. Active participation of local people is mandatory for the conservation of these forests.  相似文献   

2.
Most developing countries such as India use biomass as a primary source of energy especially in domestic sectors in the rural area. The increasing population exerts more pressure on the biomass resource thereby initiating energy crisis in the region. The issue of shortage of fuelwood in the remote mountain regions is increasing since the alternative energy resources have limitations either due to poor economic condition of the people, complex technology involved or being inaccessible due to remoteness. It is also seen that the use of traditional biomass as a source of energy will improve the livelihood conditions of the people and it will give ecological benefits to the region if other associated factors like health, gender etc. are taken care of and thus the planners aim to focus on sustaining the natural fuelwood resources. The present paper attempts to predict the future fuelwood demand based on the present consumption pattern in the upland villages of Indian Himalaya. Major consumption characteristics such as fuelwood consumption at different altitude and per capita fuelwood consumption (PCFC) are studied. Population dynamics model is postulated in order to assess future population vs. fuelwood consumption scenario, thereby projecting the future population and the future fuelwood demand in the region.It is observed that variations in fuelwood consumption exist at different altitudes in the hilly region. Mathematical modelling and time-series simulation model was proposed and validated model to predict the future expected demand of fuelwood resources in Phakot watershed. Based on the projected population and season based fuelwood requirements, the watershed will have a total fuelwood demand of 19,327 t in 2011 which is expected to reach 36,462 t in 2021. Such studies on the future resource demand trends will help in finding suitable region-specific and need-based alternative strategies for achieving sustainable fuelwood management at the micro-level.  相似文献   

3.
《Energy》1998,23(11):997-1005
Egypt depends mainly on oil and NG for 92% of total commercial energy needs. Reserve estimates are largely based on speculations. We give logistics functions for oil and NG production and consumption rates and reserves. An energy-flow diagram has been constructed for Egypt. Sectorial energy consumptions are also given. Estimates of reserves from logistic curves show that crude oil would last for about 24 yr and that NG will last for 150 yr with present production rates.  相似文献   

4.
Due to poverty, serious soil erosion and shortage of rural household energy in Loess Hilly Region, Gansu Province, China, excessive consumption of biofuel has become a critical factor underlying eco-environment degeneration. Data on rural household energy use was obtained by questionnaires, and based on substitutable analysis, environmental and economic costs under different energy consumption structures were estimated using a quantitative model. The results show that annual energy consumption per household is 2112.44 kgce and per capita 428.59 kgce, a low level. The total annual energy consumption cost per household is 1925.25 yuan, of which environmental cost is 621.13 yuan and economic cost 1304.52 yuan. Commercial energy has been used widely. The per household annual cash payment for commercial energy is 536.51 yuan, 8.69% of household net income. Exclusive use of solar energy and biogas obviously decreases energy consumption cost, cash payout and energy source availability being the main criteria for household energy choice. To compare with the actual structure of energy usage, there are clear differences in the total cost, environment cost, economic cost and cash payout for households among the four substitutable structures. All costs are lower when biogas and solar energy are used, so this structure is the primary direction that rural energy should adopt in the future.  相似文献   

5.
Biomass energy is the main energy source in rural China. The low per capita cropland in China makes it impractical to convert cropland to energy crop cultivation as in other countries; development of energy crops must not compete with food and other cash crops for prime cropland. Mulberry planted on marginal lands like land risers, land boundaries and waste slopelands in Ningnan County of China's southwestern Sichuan Province not only yielded enough leaf biomass to support a production of over 6000 t of cocoons in 2005, but also produced large amounts of woody biomass through annual pruning. Mulberry planted on marginal lands would not be replaced by food or other cash crops if cocoon prices drop. The average annual dry matter biomass of pruned mulberry branches is 1.7 kg/plant, or approximately 17.0–22.5 t/ha, which is high compared to the annual biomass growth of many fast growing trees and perennial herbaceous energy crops. Mulberry prunings exceed household needs for fuelwood because household energy requirements are met with multiple sources. Income from cocoons is the major driving force for the expansion of mulberry planting on marginal land, as lack of incentives has accounted for slow development of firewood in China. Large scale development of marginal land-based planting of mulberry can also help reduce greenhouse gas emissions to the atmosphere, conserve forests and promote biodiversity.  相似文献   

6.
The interest in increasing the participation of renewable energy sources (RES) in energy production arises with increasing population and growing demands for energy production and consumption, as well as the fact of the limited fossil fuels reserves. RES in the energy balance of any country has their share of energy, socio-economic and environmental benefits. Investment in energy sector in the RES domain enables Vojvodina Province to reduce energy dependence on the fossil fuel market.From the total RES potential in Vojvodina Province that is 1293 ktoe/year, around 1.7% is located in existing geothermal sources. There are 73 drills with a total capacity of 72.6 MW from which 65 drills are tested positive. Currently, 15 wells are in production, with a total power of 17.7 MW. There are 27 drills that have never been in production and which are perspective, with a total power of 42.8 MW.The aim of this paper is to perform data analysis of direct geothermal energy utilization according to the water temperature and geothermal fluid flow. According to the results of the analysis recommendations for geothermal energy utilization are given within certain sectors: agriculture (aquaculture and greenhouses), heating of the facilities and pools, industrial applications and balneology.  相似文献   

7.
《Biomass & bioenergy》2001,20(2):83-99
A questionnaire survey was conducted in rural and urban Kenya to establish biofuel consumption rates and patterns. The survey targeted households, commercial catering enterprises and public institutions such as schools and colleges. Firewood was the main biofuel used, mostly by rural households, who consumed the commodity at average consumption rates in the range 0.8–2.7 kg cap−1 day−1. Charcoal was mostly consumed by the urban households at weighted average rates in the range 0.18–0.69 kg cap−1 day−1. The consumption rates and patterns for these fuels by restaurants and academic institutions, and those for crop residues are also reported. The rates largely depended on the fuel availability but differed significantly among the three consumer groups and between rural and urban households. Other factors which may have influenced consumption rates are discussed. Although good fuelwood sufficiency was reported in the country in 1997, there were increasing difficulties in accessing these resources by most households, a situation having both short- and long-term implications for biofuel consumption rates and patterns.  相似文献   

8.
Rapidly rising trends of fuel consumption indicate enormous energy crisis of global proportions in near future. Following the trend, Malaysia's fuel consumption has been increasing by an annual rate of 7.2% since 1990 and has even reached 44.9 Mtoe in 2008. It is forecasted to reach 207.3 Mtoe by the year 2030. Due to serious depletion of reserves in various onshore locations, the exploration process is expanded to offshore deeper waters. Seven sedimentary basins belonging to Malaysia, in South China Sea, show great promise to be excellent sources of hydrocarbons. For deep-sea exploration fixed offshore structures are not feasible. An economical alternative is Spar platforms, which are floating structures ideal for exploration of deep water deposits. In this research, Malaysian experience in offshore hydrocarbon exploration is investigated. Various kinds of operational Spar platforms are censoriously explored and their recent technical developments are reviewed. The study reveals that Malaysia's primary energy requirements were met (in year 2008) with natural gas by 43.4% of the total, crude oil by 38.2%, coal by 15.3% and hydropower by 3.1%; indicating evidently that natural gas and crude oil are still the predominant energy sources. Out of the total energy, around 70% oil and 85% natural gas come from offshore fields. These large figures highlight the necessity to consider economically viable alternatives. Spar platform is an innovative marine structure designed to conduct such deep sea explorations. First commissioned Spar at Kikeh field of Malaysia is testimony to immense potential and possibilities of incorporating Spar platforms in the country's deep reserves for sustainable energy generation. Classic Spar, Truss Spar, Cell Spar and Cell–truss Spar are identified to be well suited for these environments. Since the offshore fields are located at waters with more than 1000 m depth, Spar platforms can be successfully installed at these Malaysian deep water fields.  相似文献   

9.
Since Taiwan imports more than 99% of energy supply from foreign countries, energy security has always been the first priority for government to formulate energy policy. The development of renewable energy not only contributes to the independence of energy supply, but also achieves benefits of economic development and environmental protection. Based upon information available to public, the present paper reassesses reserves of various renewable energies in Taiwan. The assessment includes seven kinds of renewable energies, namely, solar energy, wind power, biomass energy, wave energy, tidal energy, geothermal energy and hydropower, which are all commercialized and matured in terms of current technologies. Other renewable energies, which have not proven as matured as the aforementioned ones, are only assessed preliminarily in this paper, such as second generation of biomass, deep geothermal energy, the Kuroshio power generation and ocean thermal energy conversion.According to the estimation of this paper, the reserve of wind energy, up to 29.9 kWh/d/p (i.e., kWh per day per person), is the largest one among seven kinds of renewable energies in Taiwan, followed by 24.27 kWh/d/p of solar energy, 4.55 kWh/d/p of biomass, 4.58 kWh/d/p of ocean energy, 0.67 kWh/d/p of geothermal energy and 16.79 kWh/d/p of hydropower. If regarding biomass as a primary energy, and assuming 40% being the average efficiency to convert primary energy into electricity, the total power of the seven kinds of renewable energy reserves is about 78.03 kWh/d/p, which is equal to 2.75 times of 28.35 kWh/d/p of national power generation in 2008. If the reserves of 54.93 kWh/d/p estimated from other four kinds of renewable energies that have not technically matured yet are also taken into account, it will result that the reserves of renewable energy in Taiwan can be quite abundant.Although the results of the assessment point out that Taiwan has abundant renewable energy resources, the four inherent shortcomings – low energy density, high cost of power generation, instability of power supply, and current cost of renewable energy being still higher than that of fossil energy – have to be overcome first, before renewable energy is actually formed as a main component in national energy mix. The measures executed by government to break through these barriers further include the upgrade of the technological level, the formulation of the necessary policies, and the work together from all levels for the overall promotion.  相似文献   

10.
In order to achieve energy consumption targets, and subsequently reduce carbon emissions, China is working on energy strategies and policies aimed at actively increasing the consumption of natural gas—the lowest carbon energy of the fossil fuels, and to enhance the proportion of gas in total primary energy consumption. To do this, it is a necessary prerequisite that China must have access to adequate gas resources and production to meet demand. This paper shows that the availability of domestic gas resources are overestimated by China's authorities due to differences in classification and definitions of gas resources/reserves between China and those accepted internationally. Based on official gas resource figures, China's gas production remains low with respect to the projected demand, and will only be 164.6 bcm in 2020, far lower than the 375 bcm of forecast demand. The gap between gas production and demand will reach 210.4 bcm by 2020. Existing plans for the importation of gas and the development of unconventional gas will not close this gap in the next 10 years, and this situation will therefore present a severe challenge to China's gas security, achievement of targets in improving energy consumption structure and reducing carbon emissions.  相似文献   

11.
《Energy》2002,27(5):429-446
In 1996, China manufactured just over 100 Mt of steel and became the world's largest steel producer. Official Chinese energy consumption statistics for the steel industry include activities not directly associated with the production of steel, ‘double-count’ some coal-based energy consumption, and do not cover the entire Chinese steelmaking industry. In this paper, we make adjustements to the reported statistical data in order to provide energy use values for steel production in China that are comparable to statistics used internationally. We find that for 1996, official statistics need to be reduced by 1365 PJ to account for non-steel production activities and double-counting. Official statistics also need to be increased by 415 PJ in order to include steelmaking energy use of small plants not included in official statistics. This leads to an overall reduction of 950 PJ for steelmaking in China in 1996. Thus, the official final energy use value of 4018 PJ drops to 3067 PJ. In primary energy terms, the official primary energy use value of 4555 PJ is reduced to 3582 PJ when these adjustments are made.  相似文献   

12.
《Energy Policy》2002,30(11-12):1107-1118
The energy consumption patterns and in particular, those of the rural household and small and medium enterprises (SMEs) in Eritrea are assessed. Eritrea's total final energy consumption in 1998 was estimated to be around 619,580 toe, of which 68% was consumed by the household sector, 16% by the commercial/public sector, 13% by transport and 3% by industry. The sources of energy were 66.3% biomass based (fuelwood, dung, charcoal, agri-residue), 31% oil products and 2% electricity. It is also noted that 98% of the rural population and 20% of the urban residents do not have access to electricity. Over 80% of the energy needs of rural enterprises is met by biomass or animate/human labour. To analyse the root problems hindering the wider dissemination of modern energy services to rural areas, two key hypotheses related to policy and institutional framework were selected and tested. The findings indicate that Eritrea has general energy policies pertaining to the development of electricity, oil and renewable energy sub-sectors for the benefit of the public and the economy. The absence of sharply focussed, pro-rural energy policy and/or their policy instruments has been observed. The key problem is, however, the weakness in implementation of rural energy projects and programmes. This is mainly due to inappropriate institutional structure and/or gaps in the structure, in addition to lack of corporate culture; poor incentives for workers; and, poor linkages among the various stakeholders concerned in energy for rural development.  相似文献   

13.
Economic development in recent decades has been characterised by the increased use of fossil fuels. Clearly, a significant amount of this energy does not fall in line with the principles of sustainable development, either because of its contaminating effect or because of its non-renewable nature.Today, Navarre generates around 60% of its electricity requirements by means of wind power and small hydropower stations. On the downside, Navarre's energy consumption is above average for the European Union and its economy is growing at an annual rate in excess of 5%. The Castejón (800 MW) thermal power stations, scheduled for enlargement, generate more energy than Navarre's entire wind power sector.In terms of hydroelectric power, there are around 200 small hydropower plants in operation. In addition, the Autonomous Community of Navarre has installed a biomass plant in Sangüesa, with an installed output of 25 MW, annually generating 200 GWh through the combustion of 160,000 t of cereal straw.In addition, Navarre, specifically Tudela, is the site of the largest solar energy plant in Spain, producing 1.2 MWp, following its connection to the grid at the beginning of the year. Two thirds of the 10,080 panels are arranged in a central body and the remaining third are panels pertaining to different technologists and technologies involved in research and development.  相似文献   

14.
《Biomass & bioenergy》2006,30(4):281-288
Renewable energy sources play an important role in the Finnish energy and climate strategies which are implemented partly through the Action Plan for Renewable Energy Sources. Enhancement of wood energy plays a key role in the plan. A special emphasis is given to forest chips produced from small-sized trees from early thinnings and above-ground and below-ground residual biomass from regeneration cuttings. The production goal of forest chips is 5 million m3 solid (10 TWh) in 2010. The use of forest chips is promoted by means of environmental taxes, financial aid for investments, and financial support for research, development and commercialization of technology. In 2002, altogether 365 heating and power plants larger than 0.4 MW used forest chips. The total consumption was 1.7 million m3, the use of small houses and farms included. The growth of use is presently about 350 000 m3 per annum, but reaching the official goal will require an annual growth of 400 000 m3 during this decade.The consumption of roundwood per capita, 15 m3 per annum, is in Finland 20 times as high as the average consumption of the EU countries, respectively. Consequently, residual forest biomass is abundantly available. The capacity of heating and power plants to use forest chips is large enough to meet the goal. However, users require competitive chip prices, good quality control of fuel and reliable supply chains, and new efficient procurement systems are being developed. The paper deals with the drivers of this development: support measures of the Government; strong support to research, development and commercialization of forest chip production from the National Technology Agency Tekes; advanced infrastructure for the procurement of timber for the forest industries; positive attitude and active participation of the forest industries; the active role of leading forest machine and boiler manufacturers, and the possibility to cofire wood and peat fuels in large fluidized bed boilers so as to secure the availability of fuel in all conditions, stabilize the moisture content of fuel and reduce the emissions from combustion.  相似文献   

15.
The service sector is extraordinarily important for the European economy, as it accounts for 75% of the GDP. Yet it is also a huge consumer of energy, especially in urban environments. Municipalities have the authority to develop and manage municipal services, and as a result the European Commission drew up the Covenant of Mayors in which the signatory municipalities pledge to reduce their CO2 emissions by 20% of their 1990 rates. Sustainable Energy Action Plans (SEAPs) emerged from this covenant with the goal of analysing the current consumption patterns and compiling the actions that the municipalities should undertake in order to fulfil their pledges.This article focuses on analysing the energy consumption and greenhouse gas emissions of 978 municipal service facilities in the province of Barcelona in the year 2005. The average consumption per facility by surface area is 118.8 kWh/m2. Regarding greenhouse gas emissions, the average annual emissions in the facilities studied in the province of Barcelona were 40.0 kg CO2 eq/m2.  相似文献   

16.
The present paper deals with experimental and numerical study on the longitudinal heat transportation by an oscillatory water flow in a double tube type heat transportation pipe. Experiments were performed to measure the heat transportation rate in the ranges of 2.3 ? Wo ? 7.2 and 400 ? Remax ? 6600. The heat transportation rate was approximately 10–490 times the heat transportation rate of a straight round pipe, and it was around 1–40 times the heat conduction rate through a copper rod. Analytical heat transportation rates agreed well with the experimental ones.  相似文献   

17.
Previous estimates of environmental impacts associated with the front end of the nuclear fuel cycle (FEFC) have focused primarily on energy consumption and CO2 emissions. Results have varied widely. This work builds upon reports from operating facilities and other primary data sources to build a database of front end environmental impacts. This work also addresses land transformation and water withdrawals associated with the processes of the FEFC. These processes include uranium extraction, conversion, enrichment, fuel fabrication, depleted uranium disposition, and transportation.To allow summing the impacts across processes, all impacts were normalized per tonne of natural uranium mined as well as per MWh(e) of electricity produced, a more conventional unit for measuring environmental impacts that facilitates comparison with other studies. This conversion was based on mass balances and process efficiencies associated with the current once-through LWR fuel cycle.Total energy input is calculated at 8.7 × 10 3 GJ(e)/MWh(e) of electricity and 5.9 × 10 3 GJ(t)/MWh(e) of thermal energy. It is dominated by the energy required for uranium extraction, conversion to fluoride compound for subsequent enrichment, and enrichment. An estimate of the carbon footprint is made from the direct energy consumption at 1.7 kg CO2/MWh(e). Water use is likewise dominated by requirements of uranium extraction, totaling 154 L/MWh(e). Land use is calculated at 8 × 10 3 m2/MWh(e), over 90% of which is due to uranium extraction. Quantified impacts are limited to those resulting from activities performed within the FEFC process facilities (i.e. within the plant gates). Energy embodied in material inputs such as process chemicals and fuel cladding is identified but not explicitly quantified in this study. Inclusion of indirect energy associated with embodied energy as well as construction and decommissioning of facilities could increase the FEFC energy intensity estimate by a factor of up to 2.  相似文献   

18.
Bioenergy is the major domestic energy for rural households in developing countries due to its cheap or easy-getting characteristics. Productive use of bioenergy is an important strategy for rural households to improve not only their income, but also their health, living environment and so on. In Tibet of China, which is rich in cattle dung and firewood as the major energy sources for rural households, the efficiency of energy utilization is just about 10%. In order to improve energy utilization efficiency and the living conditions for rural residents, the Tibet Autonomous Region government introduced residential biogas model (RBM) to local households, which was a comprehensive utilization system of energy integrated with residential biogas digester, vegetable greenhouse and livestock shed. This paper aims to show the productive use of the bioenergy by the RBM, which could be depicted as the feasibility and the benefits on economic, eco-environmental and social aspects of biogas utilization, based on household questionnaires in Panam County. In RBM, biogas digester works as the biomass material supplement loop to transform originally biomass flow from single-direction to recycling-direction. The results indicate that the output of unit biogas digester could replace 1.44 t of firewood, 1.65 t of agricultural residues and 1.75 t of cattle dung, respectively. The net incremental benefit of RBM could reach 5550.72 Yuan in 15 years. The reduced amount of CO2 emission when substituted by biogas in other agricultural areas and the areas of semi-agricultural and semi-husbandry in Tibet could be (76.66–79.89) × 104 t/year and the capability for nitrogen storage could achieve (0.39–0.99) × 104 t/year. The amount of cattle dung replaced by biogas could reach 78.29 × 104 t/year; this means that the saved cattle dung, 3.51 t/hm2, could be reallocated back to cultivated land to improve the soil fertility and to keep the balance of nutrient elements in cultivated land. Biogas utilization reduces the labor opportunity costs of women compared to use of traditional bioenergy sources. It could be concluded that the productive use of bioenergy through RBM in this area has its capability to release the current pressures on biomass sources by adjusting patterns of rural energy consumption, and to improve the conditions of health, environment, economy and energy conservation.  相似文献   

19.
Industry represents a very promising application area for solar thermal technology, since it accounts for 27% of the total final energy consumption in Germany and uses 74% of its energy consumption as thermal energy. In order to develop this application area, it is necessary to know which industrial sectors have the highest potential and which processes within these sectors are most suitable for the integration of solar heat. For this paper the industrial heat consumption in Germany was analyzed, which leads to the selection of the most promising sectors within industry. Furthermore, the quantitative potential for Germany in total and for 11 selected sectors, that were identified to be most promising for the use of solar heat, was calculated. These are Chemicals, Food and beverages, Motor vehicles, Paper, Fabricated metal, Machinery and equipment, Rubber and plastic, Electrical equipment, Textiles, Printing and Wood. These sectors are analyzed to identify suitable processes for the integration of solar heat. In total the theoretical potential of solar heat for industrial processes below 300 °C in Germany accounts for 134 TWh per year, the technical potential being 16 TWh per year or 3.4% of the overall industrial heat demand. This is the highest share of the European potential of 72 TWh per year. The results of this study facilitate the prioritized application of solar thermal energy in industrial sectors and processes for Germany and other countries.  相似文献   

20.
The unsustainability of the present production–consumption energy model highlights the finite nature of conventional energy resources, as well as the environmental degradation inherent in such a model. Today's environmental policies are largely devoted to fostering the development and implementation in Europe of renewable energy technologies. This paper analyses the present and future situation of renewable energy resources in Andalusia in the south of Spain, and more specifically, of solar energy with an average potential radiation of 4.6±0.3 kW h/m2 per day. In Andalusia energy policies are generally implemented through regional development plans such as the Plan Energético de Andalucía (PLEAN)1 and the Programa Andaluz de Promoción de Energías Renovables (PROSOL).2 The principle objective of the latter programme is to implement and increase high-temperature solar thermal energy to 100 MW in 2006, even raising it to 230 MW in 2010. Regarding low-temperature solar thermal energy installations, there are plans to increase the quantity of m2/1000 installed per inhabitant from the present figure of 14 to a total of 142. Regarding individual installations of solar photovoltaic energy, the present aim is to cover 20.4% of the national objectives and 15% in installations connected to the electricity network. The geographic location of Andalusia in the south of Spain signifies that it is in a key position to play an important strategic role in the implementation of renewable energy technology in Europe, as well as providing sufficient energy for its own needs and even exporting such projects to other countries.  相似文献   

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