- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Energy Payback Time of a Rooftop Photovoltaic System in Greece
摘要： Life Cycle Analysis (LCA) is an important tool to quantitatively assess energy consumption and environmental impact of any product. Current research related to energy consumption in buildings moves towards Nearly Zero Energy Building (NZEB). In such a building, an important issue concerns the energy production by renewable sources, including on-site production. The most feasible way to achieve renewable energy utilization in a building level in Greece is by using rooftop Photovoltaic (PV) systems, also promoted in the last decade by the national legislation concerning energy conservation measures. Apart from cost-related issues and payback times, Embodied Energy (EE) and Embodied CO2 (ECO2) emissions have also to be considered against the anticipated corresponding savings. Using a particular PV system as a case study, its basic constitutive materials are determined and their masses are calculated. Embodied energy values are estimated by using embodied energy coefficients available in the international literature. Considering a specific geographic location in Greece for the building on which the PV is installed, the annual energy generated by the system is estimated based on its performance data and curves. The Energy and CO2 Payback Times (EPBT and CO2PBT) are estimated and assessed, as well as future work is suggested.
关键词： Photovoltaic systems,CO2 Payback Time,Embodied CO2,Energy Payback Time,Life Cycle Analysis,Nearly Zero Energy Building,Embodied Energy
更新于2025-09-23 15:21:01
-
Coherent TiO <sub/>2</sub> /BaTiO <sub/>3</sub> heterostructure as a functional reservoir and promoter for polysulfide intermediates
摘要： Promoting biodiesel industrialization is not only an important measure in addressing the energy crisis and global warming but is also a driver for industrial restructuring and rural development. To promote the development of the biofuel industry, the Chinese central government has set a target that biofuel will account for 15% of transport energy consumption by 2020. The macroeconomic impacts of this policy, however, are unknown. This paper estimates the economic and environmental impacts on Yunnan of meeting this target using a demand-driven input–output model for Jatropha curcas L. biodiesel. The study combines life-cycle analysis and input–output analysis to establish the industrial relationship of the biodiesel sector with other sectors. The results show that meeting the biofuel policy target in 2020 will generate 296,780 thousand job opportunities annually (man-year) and increase household income. Meeting this target will also lower carbon emission by 11.39 million tonnes of CO2 equivalent, valued at 2.41 billion Yuan. However, meeting the target will decrease tax revenue by 1.8 billion Yuan and reduce the provincial gross domestic product by 754.95 million Yuan. Thus, the industrialization of J. curcas L. biodiesel can contribute to the development of a green economy and is a positive response to the policies of energy conservation and emission reduction. The promotion of biodiesel production, however, requires a trade-off between economic and environmental targets.
关键词： carbon emission reduction,economic impact,input–output analysis,Jatropha biodiesel,life-cycle analysis
更新于2025-09-19 17:15:36
-
Life cycle analysis for laser welding of alloys
摘要： Laser welding of AISI 304, Ti6Al4V, and Inconel 625 alloy was realized. The topological and metallurgical variations in the welded region are presented brie?y and life cycle analysis for the welding process due to each alloy is introduced. The analytical tools including optical and scanning electron microscopes are used to characterize the weld sections. The energy consumption during welding and the size of the welded sections are formulated using the lump parameter analysis. The energy consumption during welding and the geometric features of the weld sites is measured. The ?ndings are compared with those obtained from the lump parameter analysis. It is found that the energy consumption predicted and obtained from the measurements are in good agreement for the welding of each material. The prediction of the weld width from the lump parameter analysis di?ers from that of the measurements; however, the di?erences are within the acceptable limits. Because of the high pressure assisting gas e?ect and the local evaporation from the weld surface, some material is ablated from the top surface of the weld site. The gravitational and the surface tension forces result in the molten material extension from the bottom side of the welded zone. The laser welding of Inconel 625 alloy has the most contribution towards environmental destruction as compared to those of other materials welded. Consequently, the materials selection for the laser welding remains crucial for minimizing the environmental impact.
关键词： Energy consumption,Laser welding,Weld geometry,Life cycle analysis
更新于2025-09-16 10:30:52
-
Life cycle analysis of a building integrated photovoltaic system operating in Bogotá, Colombia
摘要： In this study, the environmental behavior was characterized for a 840 Wp building-integrated photovoltaic (BIPV) system installed in the Department of Physics of the Faculty of Sciences at the National University of Colombia, Bogota campus. The methodology focused on the application of the international technical standards for Life Cycle Analysis (LCA) from cradle to grave based on the NTC ISO 14040 and NTC ISO 1404 standards, which regulate the methodological procedure. This article is based on comparing the potential of environmental impacts of five power generation scenarios, taking as reference the installation of the photovoltaic system (PV) at the University. During the analysis it was possible to determine that energy generation with coal has a greatest environmental impact compared with photovoltaics: 84% and 6% respectively. This represents 1138.8 gCO2eq/kWh for coal, compared to 35 gCO2eq/kWh for the PV system.
关键词： Solar energy,Solar cells,Greenhouse emissions,Photovoltaic systems,Life cycle analysis
更新于2025-09-11 14:15:04
-
Challenges and research needs in life cycle analysis of building-integrated photovoltaic
摘要： Building-integrated photovoltaic (BIPV) is a promising solar energy technology that looks set to grow in popularity in the pursuit of a sustainable future. It has the potential to mitigate some of the main concerns over ground-mounted solar energy systems such as land use. However, there is an apparent gap in our understanding of its life cycle environmental impacts. Very few life cycle analysis (LCA) studies have evaluated BIPV comprehensively in comparison with standalone PV systems and other energy technologies. In this paper, we review the limited existing LCA studies on BIPV and identify the challenges and future research needs. The findings will help researchers, industries and policy makers better understand the environmental sustainability of BIPV to facilitate its development.
关键词： building-integrated photovoltaic,environmental sustainability,life cycle analysis,solar energy
更新于2025-09-11 14:15:04