Energy and greenhouse-gas emissions in irrigated agriculture of SE (southeast) Spain. Effects of alternative water supply scenarios

Life-cycle energy impacts for adapting an urban water supply system to droughts

Seawater desalination is considered a technique with high water supply potential and has become an emerging alternative for freshwater supply in China. The increase of the capacity also increases energy consumption and greenhouse gases (GHG) emissions, which has not been well investigated in studies. This study has analyzed the current development of seawater desalination in China, including the capacity, distribution, processes, as well as the desalted water use. Energy consumption and GHG emissions of overall desalination in China, as well as for the provinces, are calculated covering the period of 2006–2016. The unit product cost of seawater desalination plants specifying processes is also estimated. The results showed that 1) The installed capacity maintained increased from 2006 to 2016, and reverse osmosis is the major process used for seawater desalination in China. 2) The energy consumption increased from 81 MWh/y to 1,561 MWh/y during the 11 years. The overall GHG emission increase from 85 Mt CO2eq/y to 1,628 Mt CO2eq/y. Tianjin had the largest GHG emissions, following are Hebei and Shandong, with emissions of 4.1 Mt CO2eq/y, 2.2 Mt CO2eq/y. and 1.0 Mt CO2eq/y. 3) The unit product cost of seawater desalination is higher than other water supply alternatives, and it differentiates the desalination processes. The average unit product cost of the reverse osmosis process is 0.96 USD and 2.5 USD for the multiple-effect distillation process. The potential for future works should specify different energy forms, e.g. heat and power. Alternatives of process integration should be investigated—e.g. efficiency of using the energy, heat integration, and renewables in water desalination, as well as the utilization of total site heat integration.

In this paper, we used the life-cycle analysis (LCA) method to evaluate the energy consumption and greenhouse gas (GHG) emissions of natural gas (NG) distributed generation (DG) projects in China. We took the China Resources Snow Breweries (CRSB) NG DG project in Sichuan province of China as a base scenario and compared its life cycle energy consumption and GHG emissions performance against five further scenarios. We found the CRSB DG project (all energy input is NG) can reduce GHG emissions by 22%, but increase energy consumption by 12% relative to the scenario, using coal combined with grid electricity as an energy input. The LCA also indicated that the CRSB project can save 24% of energy and reduce GHG emissions by 48% relative to the all-coal scenario. The studied NG-based DG project presents major GHG emissions reduction advantages over the traditional centralized energy system. Moreover, this reduction of energy consumption and GHG emissions can be expanded if the extra electricity from the DG project can be supplied to the public grid. The action of combining renewable energy into the NG DG system can also strengthen the dual merit of energy conservation and GHG emissions reduction. The marginal CO2 abatement cost of the studied project is about 51 USD/ton CO2 equivalent, which is relatively low. Policymakers are recommended to support NG DG technology development and application in China and globally to boost NG utilization and control GHG emissions.

The potential challenge for the effective GHG emissions mitigation of urban energy consumption: A case study of Macau

Climate change and water security: Estimating the greenhouse gas costs of achieving water security through investments in modern irrigation technology

Aluminum production is a major energy consumer and important source of greenhouse gas (GHG) emissions globally. Estimation of the energy consumption and GHG emissions caused by aluminum production in China has attracted widespread attention because China produces more than half of the global aluminum. This paper conducted life cycle (LC) energy consumption and GHG emissions analysis of primary and recycled aluminum in China for the year 2020, considering the provincial differences on both the scale of self-generated electricity consumed in primary aluminum production and the generation source of grid electricity. Potentials for energy saving and GHG emissions reductions were also investigated. The results indicate that there are 157,207 MJ of primary fossil energy (PE) consumption and 15,947 kg CO2-eq of GHG emissions per ton of primary aluminum ingot production in China, with the LC GHG emissions as high as 1.5–3.5 times that of developed economies. The LC PE consumption and GHG emissions of recycled aluminum are very low, only 7.5% and 5.3% that of primary aluminum, respectively. Provincial-level results indicate that the LC PE and GHG emissions intensities of primary aluminum in the main production areas are generally higher while those of recycled aluminum are lower in the main production areas. LC PE consumption and GHG emissions can be significantly reduced by decreasing electricity consumption, self-generated electricity management, low-carbon grid electricity development, and industrial relocation. Based on this study, policy suggestions for China’s aluminum industry are proposed. Recycled aluminum industry development, restriction of self-generated electricity, low-carbon electricity utilization, and industrial relocation should be promoted as they are highly helpful for reducing the LC PE consumption and GHG emissions of the aluminum industry. In addition, it is recommended that the central government considers the differences among provinces when designing and implementing policies.

Curbing greenhouse gas (GHG) emissions to combat climate change is a major global challenge. Although irrigated agriculture consumes considerable energy that generates GHG emissions, the biomass produced also represents an important CO2 sink, which can counterbalance the emissions. The source of the water supply considerably influences the irrigation energy consumption and, consequently, the resulting carbon footprint. This study evaluates the potential impact on the carbon footprint of partially and fully replacing the conventional supply from Tagus–Segura water transfer (TSWT) with desalinated seawater (DSW) in the irrigation districts of the Segura River basin (south-eastern Spain). The results provide evidence that the crop GHG emissions depend largely on the water source and, consequently, its carbon footprint. In this sense, in the hypothetical scenario of the TSWT being completely replaced with DSW, GHG emissions may increase by up to 50% and the carbon balance could be reduced by 41%. However, even in this unfavourable situation, irrigated agriculture in the study area could still act as a CO2 sink with a negative total and specific carbon balance of −707,276 t CO2/year and −8.10 t CO2/ha-year, respectively. This study provides significant policy implications for understanding the water–energy–food nexus in water-scarce regions.

PDF HTML阅读 XML下载 导出引用 引用提醒 西安市温室气体排放的动态分析及等级评估 DOI: 10.5846/stxb201305271199 作者: 作者单位: 陕西师范大学旅游与环境学院,陕西师范大学旅游与环境学院,陕西师范大学旅游与环境学院,陕西师范大学旅游与环境学院,陕西师范大学旅游与环境学院,陕西师范大学旅游与环境学院 作者简介: 通讯作者: 中图分类号: 基金项目: 陕西省软科学研究计划项目(2012KRM48);国家社会科学基金项目(14XKS019);黄土高原土壤侵蚀与旱地农业国家重点实验室基金(10501-1214) Dynamic analysis of greenhouse gas emission and evaluation of the extent of emissions in Xi'an City, China Author: Affiliation: College of Tourism and Environmental Sciences, Shaanxi Normal University,,,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为了解西安市温室气体排放的动态规律和排放水平,基于全球标杆的温室气体排放等级评价方法,并采用国际公认的《2006年IPCC国家温室气体清单指南》和基于IPCC的《省级温室气体编制指南》推荐的方法对西安市的温室气体排放进行了动态分析和排放等级评估。结果表明,从1995年到2011年,西安市温室气体排放呈快速上升趋势,16年间温室气体排放量从1207.16×104t 上升为3934.17×104t,年均增高7.66%。增幅最高的是水泥温室气体(年均增高11.75%)、废弃物(8.77%)和能源(7.63%),农业年均降低1.74%,林业固碳年圴增加3.56%。从温室气体构成看,能源占80.13%-90.55%,水泥占1.75%-7.49%,农业占1.86%-8.01%,林业固碳占-2.58%—5.22%,废物处理占7.52%-16.38%。可见能源消费的增加是导致西安市温室气体排放增长的主要原因,林业碳汇能力有待提高。万元GDP温室气体排放不断降低,说明西安市碳减排方面的科技进步在不断提高。人均、单位面积温室气体排放量和排放指数增速很快,年均增幅分别达5.84%、7.66%和6.84%。西安市温室气体排放等级持续增高,16年间从较低等级(Ⅰc)上升为中下等级(Ⅱa),目前距应对气候变暖目标(Ⅰb)已高出两个亚级,温室气体排放增高的趋势不容忽视。 Abstract:Global warming caused by greenhouse gas emission may cause severe environmental and social problems. Greenhouse gas accounting has become a hotly debated research topic. Internationally, some research has been undertaken on greenhouse gas accounting and some progress has been made; however, there are many shortcomings in this field. The main problem is that current research is mainly focused on carbon emission, particularly carbon emission from fossil fuel combustion, and is less involved in carbon fixation and ways of assessing regional carbon emission levels. In addition, the actual emission figures for greenhouse gases nationally and regionally in China were unknown. Although much research relates to carbon emission, the results are difficult to compare owing to inconsistent research methods and standards. Xi'an City, a historical and cultural tourist city in China, lies in the radiation center of the Guan-Tian economic zone. It is the economic, cultural, education, manufacturing and high-tech industry hub of northwest China. Xi'an will be an international metropolis in China in the near future. However, research relating to the greenhouse gas footprint in Xi'an is scarce. In this paper, the author proposed an evaluation system for greenhouse gas (GHG) emission to the level of global benchmarking using the methods recommended by the 2006 IPCC Guidelines for National Greenhouse Gas Inventories and the Chinese Guidelines for Provincial Greenhouse Gas Inventories, and using this a dynamic analysis of GHG emission and evaluation of the extent of GHG emission in Xi'an City was performed. The results showed that, from 1995 to 2011, GHG emission showed a rapidly rising trend in Xi'an City, increasing from 1207.16×104t to 3934.17×104t, which represented an average annual increase of 7.66%. The largest increase was for cement (an average annual increase of 11.75%), waste (8.77%) and energy (7.63%) GHG. Agricultural GHG emission showed an annual reduction of 1.74%, while forestry carbon sequestration showed an annual average increase of 3.56%. In a breakdown of emissions, energy GHG accounted for 80.13%-90.55%, cement GHG for 1.75%-7.49%, agricultural GHG for 1.86%-8.01%, forestry carbon sequestration for -2.58%—5.22%, and waste treatment GHG for 7.52%-16.38%. An increase in energy consumption is the main cause of the increase in GHG emission in Xi'an City, and forestry carbon sequestration capacity needs to be improved. In Xi'an City, the GHG emission per 10,000 Yuan GDP was constantly decreasing, and progress in the science and technology of carbon emission has continuously improved. The GHG emission per capita, per unit area and per carbon emission index has increased very quickly, showing an average annual increase of 5.84%, 7.66% and 6.84% respectively. The carbon emission state in Xi'an City has increased continually from a low level (Ⅰc) to a middle level (Ⅱa), which was an increase of two sub-grades and which was two grades higher than the target set for the control of global climate warming. The increasing trend in carbon emission cannot be ignored. 参考文献 相似文献 引证文献

Identifying greenhouse gas emission reduction potentials through large-scale photovoltaic-driven seawater desalination

Impacts of green certification programs on energy consumption and GHG emissions in buildings: A spatial regression approach

Between 1999 and 2007, several successive years of severe drought put South East Queensland's water supply under immense pressure. The decision was taken in 2005 to build a seawater desalination plant and three water recycling advanced treatment plants as part of a large investment plan to secure the region's potable water supply. The infrastructure built and commissioned in the past 3 years has a combined capacity producing more than 350,000 m3 per day of very high quality water that can be used either directly (seawater desalination) or indirectly (recycled water) for supplying drinking water. All the plants primarily rely on reverse osmosis membranes for water purification which is an effective and reliable barrier to contaminants, but also requires high energy consumption and a high level of pre-treatment and chemicals. In this paper, the actual energy consumption of two of the plants (the seawater desalination plant and one water recycling plant) was investigated with the perspective of drinking water production over the July 2009–June 2010 period. Eolia™ Potable Water, a Life Cycle Analysis tool developed by Veolia Environnement Research & Innovation, was used to model the processes and estimate the greenhouse gases (GHG) emissions from both plants. As expected, the energy requirement of the desalination was higher (approximately 2.2 times) than the water recycling plant. The plants were found to be significantly more energy efficient when operated at higher flow. In both cases, the purchase of electrical energy represented by far the major contribution to GHG emissions. Indirect GHG emissions from chemical consumption could be reduced at the water recycling plant by optimising the dose of ferric chloride used at the plant and sourcing the chemical from a less distant supplier.

Electric vehicles (EVs) are widely promoted as clean alternatives to conventional vehicles for reducing greenhouse gas (GHG) emissions from ground transportation. However, the battery undergoes a sophisticated degradation process during EV operations and its effects on EV energy consumption and GHG emissions are unknown. Here we show on a typical 24 kWh lithium-manganese-oxide–graphite battery pack that the degradation of EV battery can be mathematically modeled to predict battery life and to study its effects on energy consumption and GHG emissions from EV operations. We found that under US state-level average driving conditions, the battery life is ranging between 5.2 years in Florida and 13.3 years in Alaska under 30% battery degradation limit. The battery degradation will cause a 11.5–16.2% increase in energy consumption and GHG emissions per km driven at 30% capacity loss. This study provides a robust analytical approach and results for supporting policy making in prioritizing EV deployment in the U.S.

Analysis of life-cycle GHG emissions for iron ore mining and processing in China—Uncertainty and trends

Life cycle assessment of the energy consumption and GHG emissions of state-of-the-art automotive battery cell production

The sector with the higher weight in final energy consumption is the transport sector, reflecting the one responsible for most greenhouse gas (GHG) emissions. In this context, and given the increasing penetration of zero or low GHG emissions vehicles with high energy efficiency, this work intends to contribute to the future identification of the impact of the transport sector on energy consumption and resulting emissions. It aims at identifying the energy consumption in the sector and quantify the GHG levels from the comparative analysis of the increase of electric based vehicle fleet in detriment of those based in internal combustion engines, considering five scenarios until the year 2030. The study is applied in mainland Portugal considering the fleet of light passenger and commercial vehicles, which comprise the vast majority of the Portuguese fleet. The Bottom-up model, where the hierarchical tree detailing is constructed from detail to the whole, is applied to the study to determine the energy consumption and GHG emissions variables. The analysis is performed through the application of the simulation tool Long-range Energy Alternatives Planning system (LEAP) of scenario-based and integrated modelling, herein utilized to determine energy consumption and account for GHG emission sources. Results show that the increase of electric vehicles directly influences the reduction of GHG emissions and final energy consumption while electric energy consumption increases.