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1.
By building on the first part of our analysis, this second part attempts to provide a further understanding of the UK society's metabolism, its impact and offer policy suggestions that could promote a shift towards sustainability. The methodologies employed in this second part include Exergy Analysis (EA) and Extended Exergy Analysis (EEA). Exergy inputs and outputs amounted to 17423.9 and 11888.7 PJ, respectively, with energy carries, mainly fossil fuels, being both the predominant inputs (15597.1 PJ) and outputs (5147.1 PJ). Exergy consumption and efficiency for various economic sectors and subsectors have been calculated with the residential and service sector showing the lowest exergy conversion efficiencies (11.2% and 12.3%, respectively) while certain industrial subsectors, such as the aluminium and iron/steel industries showed the highest exergy conversion factors (67.0 and 62.1%). Extended exergy efficiencies were somewhat different owing to the different calculation procedure. Extended exergy efficiencies were 91.4% for the extraction sector, 38.9% for the conversion sector, 49.1% for the agriculture sector, 31.5% for the transportation sector, 38.6% for the industrial sector and 80.0% for the tertiary sector.  相似文献   

2.
Between 1995 and 2010, the total energy intensity (E/GDP, PJ/Gross Domestic Product in 2002$) of the Canadian economy declined by 23% or − 2.64 MJ/$. To understand why, the Logarithmic Mean Divisia Index (LMD-I) method was used to decompose a large body of government statistical data supporting the observed E/GDP decline. The analysis shows that (a) 48% (1.27 MJ/$) of the decline was associated with an inter-sector structural change in the economy (i.e. an increased contribution to the total GDP of the low energy-using commercial and institutional sector compared with the high energy-using manufacturing and heavy industry sectors); (b) 24% (0.62 MJ/$) was attributed to the impact of the Canadian GDP growing faster than population; (c) 22% (0.58 MJ/$) of the decline was associated with an overall decrease in business energy intensity. A deeper analysis of business sectors shows a positive impact of 0.4 MJ/$ from increased energy intensity in the oil and gas sector, offset by a 0.98 MJ/$ decline due to energy intensity declines in the other business sectors; (d) 6.3% (0.17 MJ/$) of the decline was associated with an improvement in the energy intensity of households, mostly from residential energy use rather than personal transportation energy use. These results provide insights for policy makers regarding those aspects of the Canadian economy that contribute to, or work against, efforts to transform energy systems toward sustainability.  相似文献   

3.
This paper is an attempt to determine the potential for solar water heating (SWH) in South Africa and the prospects for its implementation between 2010 and 2030. It outlines the energy market conditions, the energy requirements related to residential and commercial water heating in the country and the solar water heating market dynamics and challenges. It was estimated that 98% of the potential is in the residential sector and the rest in the commercial sector. The total thermal demand for 20 years for water heating was estimated to 2.2 EJ. A ‘Moderate SWH implementation’ will provide 0.83 EJ of clean energy until 2030 and estimated cost savings of 231 billion rand. For an ‘Accelerated SWH implementation’ these figures are 1.3 EJ and 369 billion rand. The estimated accumulated reduction of CO2 emissions due to SWH can be as high as 297 Mt. The increased affordability of residential hot water due to SWH is an important social factor and solar water heating has a strong social effect.  相似文献   

4.
《Energy》2005,30(5):649-675
The extraction, conversion, and use of energy carriers and materials in the Norwegian society in 2000 were investigated by Sciubba's method of extended-exergy accounting (EEA). In this method, extended-exergy (EE) values are assigned to labor and capital fluxes in addition to thermomechanical and chemical exergy values. The interchange of resources and products was quantified in terms of energy and exergy between seven sectors of the society and between the sectors and other countries. The extraction of resources from the environment and the discharge and deposit of waste were also included in the analysis. In the extraction sector, the exergy and EE conversion efficiencies both were 95%, and in the conversion sector both were approximately 76%. These two sectors are, respectively, dominated by oil and gas extraction and hydropower conversion. The third sector—agriculture, forestry, the fisheries, and food industry—had a lower exergy output to input ratio, 45%, whereas the EE conversion efficiency was 62%. A fourth sector, manufacturing industry, was dominated by paper, metal, and also chemical industry, and the efficiencies were 50 and 69%, respectively. In the transportation and service sectors, the labor and capital fluxes dominated the EEA, giving EE efficiencies of 63 and 75%, respectively, whereas the exergy efficiencies were 19 and 26%, respectively. In the seventh sector, the domestic sector (i.e. households), there was a close to zero energy and exergy output in this approach, since no products or resources were transferred to the other sectors except waste for re-circulation. However, the EE output of this sector was greater than the input, since labor is supplied from this sector to the other sectors.  相似文献   

5.
《Biomass & bioenergy》2006,30(5):405-421
Biomass production is a promising alternative for the Czech Republic's (CZ) agricultural sector. Biomass could cover the domestic bio-energy demand of 250 PJ a−1 (predicted for 2030), and could be exported as bio-fuels to other EU countries. This study assesses the CZ's biomass production potential on a regional level and provides cost–supply curves for biomass from energy crops and agricultural and forestry residues. Agricultural productivity and the amount of land available for energy crop production are key variables in determining biomass potentials. Six scenarios for 2030 with different crop-yield levels, feed conversion efficiencies and land allocation procedures were built. The demand for food and fodder production was derived from FAO predictions for 2030. Biomass potential in the CZ is mainly determined by the development of food and fodder crop yields because the amount of land available for energy crop production increases with increasing productivity of food and fodder crops. In most scenarios the NUTS-3 regions CZ020, 31 and 32 provided the most land for energy-crop production and the highest biomass potentials. About 110 PJ a−1, mostly from agricultural and forestry residues, can be provided from biomass when the present Czech agricultural productivity is maintained. About 195 PJ a−1 (105 PJ from energy crops) can be provided when production systems are optimised with regard to fertilizer regimes and 365 PJ a−1 (290 PJ from energy crops) when the yield level of Dutch agriculture is reached. Costs for woody biomass decrease with increasing plantation yield and range between 2.58 and 4.76  GJ−1. It was concluded that Czech agriculture could provide enough biomass for domestic demand and for export if agricultural productivity is increased.  相似文献   

6.
The EUBIONET III project has boosted (i) sustainable, transparent international biomass fuel trade, (ii) investments in best practice technologies and (iii) new services on biomass heat sector. Furthermore, it identified cost-efficient and value-adding use of biomass for energy and industry. The aims of this article are to provide a synthesis of the key results of this project. Estimated annual solid biomass potential in the EU-27 is almost 6600 PJ (157 Mtoe), of which 48% is currently utilised. The greatest potential for increased use lies in forest residues and herbaceous biomass. Trade barriers have been evaluated and some solutions suggested such as CN codes for wood pellets and price indexes for industrial wood pellets and wood chips. The analysis of wood pellet and wood chip prices revealed large difference amongst EU countries, but also that on the short term prices of woody and fossil fuels are barely correlated. Sustainable production and use of solid biomass are also deemed important by most European stakeholders, and many support the introduction of harmonised sustainability criteria, albeit under a number of preconditions. The study identified also that a number of woody and agro-industrial residue streams remain un- or underutilised. The estimated European total potential of agro-industrial sources is more than 250 PJ (7.2 Mtoe), the amount of unutilised woody biomass (the annual increment of growing stock) even amounts to 3150 PJ (75 Mtoe). Finally 35 case studies of biomass heating substituting fossil fuels were carried out, showing that the potential to reduce GHG emissions ranges between 90 and 98%, while costs are very similar to fossil fuel heating systems. Overall, we conclude that solid biomass is growing strongly, and is likely to heavily contribute to the EU renewable energy targets in the coming decade.  相似文献   

7.
The need to increase energy security and promote development, especially in rural areas has forced many developing countries in southern Africa, like Mozambique to take several actions toward development of several infrastructures and legislations for production and use of liquid biofuels. The main objective of this study is to present the energy situation in Mozambique and assess the potential for energy generation from widely available renewable sources including residues from agricultural crops and forest industry. The country is endowed with great potential for biofuels, solar, hydro and wind energy production. The energy production today is, however, far from fulfilling energy needs of the country, and the majority of people are still not benefiting from these resources. The potential of total residues from agricultural sector and forest industry is estimated to be around 128 PJ. This amount of energy covers almost half of the combined production of charcoal and firewood which amounted to approximately 298 PJ in 2006. However, such amount of energy resources is wasted and is not visible on national energy statistics.  相似文献   

8.
《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   

9.
The practice of viticulture and winemaking is highly dependent upon the weather and climate. Any future changes in the seasons, their duration, local maximum, minimum and mean temperatures, frost occurrence and heat accumulation could have a major impact on the winegrowing areas of the world. Given that the winegrowing industry has substantial energy requirements and is directly influenced by any changes in climate, the industry should be at the forefront in promoting the case of energy efficiency and the adoption of renewable technologies. Solar renewables in the form of solar thermal and photovoltaics (PVs) offer a complimentary solution to many winegrowing processes. This paper examines the limited number of world wineries that have adopted solar renewables and presents a viable case for their wide scale integration into the industry.The paper presents a range of viticultural and winemaking processes where solar energy can be directly or indirectly applied and suggests the potential for solar energy in making substantial savings in both energy use and greenhouse gas emissions. In 2005, almost 8 million hectares were under vines producing 40.2 million tonnes of grapes for crushing. The total global energy use within the winemaking industry is estimated at over 105 PJ emitting nearly 16 million tonnes of CO2. If ancillary industries, such as bottle making and transportation are included, the total carbon footprint of the industry is estimated at over 76 million tonnes of CO2. This paper calculates that if the commercial winemaking establishments in the ‘developed’ wine producing regions of the world integrated a ‘small’ solar installation into their wineries, the potential savings are 18.3% or 19.24 PJ of the energy used in the global winemaking industry.  相似文献   

10.
The cement industry represents one of the most energy intensive sectors in Taiwan. Energy audits are the direct tools which are employed to help reduce energy consumption. The objectives of energy audits are to establish energy audit systems, provide on-site energy audit service and reduce production cost. This study summarized the energy savings implemented in Taiwan's cement industry; the data were obtained from the on-line Energy Declaration System in 2010. The total implemented energy savings amounted to 68,512 kilo liter of crude oil equivalent (KLOE). The energy audit group audited seven Taiwanese cement plants in 2011 and revealed an energy saving potential of 2571.6 MWh of electricity and 1002.8 KLOE of thermal energy. The total potential energy saving was 1708.5 KL of crude oil equivalent (KLOE), equivalent to a 4560 t reduction in CO2 emissions, representing the annual CO2 absorption capacity of a 122 ha forest plantation.  相似文献   

11.
A survey of household energy consumption pattern has been carried out in a village, Bibipur, district Jind, Haryana, India, during 2004. The households surveyed covered heterogeneous population belonging to different income groups, education groups and social groups. Studies were made on the total energy available, total energy required and energy consumption in different sectors domestic, agricultural, transport, rural industries and miscellaneous uses. The total energy available from all the sources (animate, biomass/non-conventional and inanimate sources) in the village is 468,205 MJ and the requirement for all the activities and from all the resources is 592,220 MJ. There is a big gap between energy supply and demand for the village. There is more availability of non-conventional energy resources as compared to conventional energy resources and some resources are unexploited. Therefore, to meet the balance of energy demand and supply, non-conventional resources should be exploited.In domestic sector, maximum energy is used in cooking (52.1%) and 45% of it is supplied from non-conventional energy sources and 10% from conventional energy sources. Calculations were made by considering all the energy resources for average per capita energy consumption and it was 20.02 MJ/day per capita. Electricity is used mainly for lighting and power, while gas is preferred for cooking.In agricultural sector, energy consumption for different activities was calculated and it was found that maximum energy consumption is in irrigation (41.7%) and minimum in transplanting. In agricultural sector, maximum energy comes from conventional energy sources (about 60%) and from non-conventional energy sources it is only about 30%. From the study, it was found that maximum population having good economic conditions like electricity very much as an energy source followed by LPG, biogas, coal, firewood and agricultural residues.  相似文献   

12.
Municipal residue biomass (MRB) in the municipal solid waste (MSW) stream is a potential year-round bioenergy feedstock. A method is developed to estimate the amount of residue biomass generated by the end-user at the scale of a country using a throughput approach. Given the trade balance of food and forestry products, the amount of MRB generated is calculated by estimating product lifetimes, discard rates, rates of access to MSW collection services, and biomass recovery rates. A wet tonne of MRB could be converted into about 8 GJ of energy and 640 kg of carbon dioxide (CO2) emissions, or buried in a landfill where it would decompose into 1800 kg of CO2 equivalent (in terms of global warming potential) methane (CH4) and CO2 emissions. It is estimated that approximately 1.5 Gt y?1 of MRB are currently collected worldwide. The energy content of this biomass is approximately 12 EJ, but only a fraction is currently utilized. An integrated assessment model is used to project future MRB generation and its utilization for energy, with and without a hypothetical climate policy to stabilize atmospheric CO2 concentrations. Given an anticipated price for biomass energy (and carbon under a policy scenario), by the end of the century, it is projected that nearly 60% of global MRB would be converted to about 8 EJ y?1 of energy in a reference scenario, and nearly all of global MRB would be converted into 16 EJ y?1 of energy by the end of the century under a climate policy scenario.  相似文献   

13.
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   

14.
This study analyzes how international climate regimes affect cost-efficiency of fuel choices in the transportation sector. The analysis is carried out with a regionalized version of the Global Energy Transition model, GET-R 6.0. Two different carbon dioxide (CO2) reduction scenarios are applied, both meeting an atmospheric CO2 concentration target of 450 ppm by the year 2100. The first scenario, “global cap” (GC), uses a global cap on CO2 emissions, and global emissions trading is allowed. In the second scenario, “regional caps” (RC), industrialized regions start to reduce their CO2 emissions by 2010 while developing regions may wait several decades and emission reductions are not tradable across regions. In this second scenario, CO2 emissions are assumed to meet an equal per capita distribution of 1.0 tC/capita, in all six regions, by 2040; emissions then follow a common reduction path, toward approximately 0.2 tC/capita by 2100. Three main results emerge from our analysis: (i) the use of biofuels in the industrialized regions is significantly higher in RC than in GC; (ii) the use of biofuels in RC actually increases the weaker (i.e., higher) the CO2 concentration target (up to 550 ppm); and (iii) biofuels never play a dominant role in the transportation sector. We find that biofuels may play a more important role in industrialized countries if these take on their responsibilities and reduce their emissions before developing countries start reducing their emissions, compared to the case in which all countries take action under a global cap and trade emission reduction regime.  相似文献   

15.
Industrial parks have become the effective strategies for government to promote sustainable economic development due to the following advantages: shared infrastructure and concentrated industrial activities within planned areas. However, due to intensive energy consumption and dependence on fossil fuels, industrial parks have become the main areas for greenhouse gas emissions. Therefore, it is critical to quantify their carbon footprints so that appropriate emission reduction policies can be raised. The objective of this paper is to seek an appropriate method on evaluating the carbon footprint of one industrial park. The tiered hybrid LCA method was selected due to its advantages over other methods. Shenyang Economic and Technological Development Zone (SETDZ), a typical comprehensive industrial park in China, was chosen as a case study park. The results show that the total life cycle carbon footprint of SETDZ was 15.29 Mt, including 6.81 Mt onsite (direct) carbon footprint, 8.47 Mt upstream carbon footprint, and only 3201 t downstream carbon footprint. Analysis from industrial sector perspectives shows that chemical industry and manufacture of general purpose machinery and special purposes machinery sector were the two largest sectors for life cycle carbon footprint. Such a sector analysis may be useful for investigation of appropriate emission reduction policies.  相似文献   

16.
The study was conducted to determine the consequences of a carbon tax, equal to an estimated social cost of carbon of $37.2/Mg, on household electricity cost, and to determine if a carbon tax would be sufficient to incentivize households to install either a grid-tied solar or wind system. U.S. Department of Energy hourly residential profiles for five locations, 20 years of hourly weather data, prevailing electricity pricing rate schedules, and purchase prices and solar panel and wind turbine power output response functions, were used to address the objectives. Two commercially available household solar panels (4 kW, 12 kW), two wind turbines (6 kW, 12 kW), and two price rate structures (traditional meter, smart meter) were considered. Averaged across the five households, the carbon tax is expected to reduce annual consumption by 4.4% (552 kWh/year) for traditional meter households and by 4.9% (611 kWh/year) for households charged smart meter rates. The carbon tax increases electricity cost by 19% ($202/year). For a household cost of $202/year the carbon tax is expected to reduce social costs by $11. Annual carbon tax collections of $234/household are expected. Adding the carbon tax was found to be insufficient to incentivize households to install either a solar panel or wind turbine system. Installation of a 4 kW solar system would increase the annual cost by $1546 (247%) and decrease CO2 emissions by 38% (2526 kg) valued at $94/household. The consequence of a carbon tax would depend largely on how the proceeds of the tax are used.  相似文献   

17.
This paper presents and analyses international solid biofuel trade and concludes upon interactions with bioenergy policies and market factors. It shows that trade has grown from about 56 to 300 PJ between 2000 and 2010. Wood pellets grew strongest, i.e. from 8.5 to 120 PJ. Other relevant streams by 2010 included wood waste (77 PJ), fuelwood (76 PJ), wood chips (17 PJ), residues (9 PJ), and roundwood (2.4 PJ). Intra-EU trade covered two thirds of global trade by 2010. Underlying markets are highly heterogeneous; generally though trade evolved whenever supply side market factors coincided with existing/emerging demand patterns. Market factors and policies both defined trade volumes; though policy changes did not have as prominent effects on trade developments as in the liquid biofuel sector. Economic viability is the key limiting factor. Main exporting countries have low feedstock costs and already existing wood processing industries. Trade-relevant aspects are the commodity's monetary value; determined by its homogeneity, heating value, and bulk density. Consumer markets are diverse: in residential heating, demand/trade patterns have been influenced by local biofuel availability and short-term price signals, i.e. mainly price competitiveness and investment support for boilers/stoves. Commodities are mainly sourced regionally, but price differences have triggered a growing trade. The industrial segment is greatly influenced by policy frameworks but more mature (e.g. established routes). Trade is strictly linked to margins (defined mainly by policies) and combustion technologies. Uncertainties in the analysis are due to data gaps across and within databases regarding import/export declarations. To estimate bioenergy related trade, anecdotal data was indispensable. We believe datasets should be streamlined across international institutions to eventually enable reporting of global trade beyond digit-6-level. Research is needed to provide further insights into informal markets. Interrelations between trade factors are particularly relevant when mapping future trade streams under different policy/trade regime scenarios.  相似文献   

18.
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   

19.
Refrigeration has become an essential part of the food chain. It is used in all stages of the chain, from food processing, to distribution, retail and final consumption in the home. The food industry employs both chilling and freezing processes where the food is cooled from ambient to temperatures above 0 °C in the former and between ?18 °C and ?35 °C in the latter to slow the physical, microbiological and chemical activities that cause deterioration in foods. In these processes mechanical refrigeration technologies are invariably employed that contribute significantly to the environmental impacts of the food sector both through direct and indirect greenhouse gas emissions. To reduce these emissions, research and development worldwide is aimed at both improving the performance of conventional systems and the development of new refrigeration technologies of potentially much lower environmental impacts. This paper provides a brief review of both current state of the art technologies and emerging refrigeration technologies that have the potential to reduce the environmental impacts of refrigeration in the food industry. The paper also highlights research and development needs to accelerate the development and adoption of these technologies by the food sector.  相似文献   

20.
Consumption accounting of urban greenhouse gas emissions is preferable to production accounting, because cities are open systems which depend on the import of large quantities of externally produced goods. In this paper we use environmental input–output analysis to construct CO2 production and consumption accounting inventories for Xiamen, a rapidly developing coastal city in southeast China. We found that, in 2007, total emissions embodied in production were 21.8 Mt CO2, of which 17.1 Mt CO2 were embodied in exports and 4.7 Mt CO2 resulted from local demand on local production. If the large amounts of emissions embodied in the Xiamen reprocessing trade are excluded from the analysis, total imported emissions were 12.2 Mt CO2, consumption emissions were 16.9 Mt CO2, and Xiamen was a net exporter of 4.9 Mt CO2. Although Xiamen's rapid economic growth is dependent on large-scale flows of embodied emissions, most of these emissions are not produced or consumed within the city system.  相似文献   

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