Analysis of scenarios for the reduction of energy consumption and GHG emissions in transport in the Basque Country

Fossil energy depletion and fight against climate change force humanity to decarbonize the economy. By year 2050 CO₂ emissions will have to reduce globally at least 85%, and probably over 95% in developed countries.The modeling of the transportation of people and commodities in the Basque Autonomous Community (Spain) in year 2008 has allowed us to draw some conclusions about the challenges ahead. The exploration of several scenarios modeled in order to reduce energy consumption in transport shows that mobility in a decarbonized world will have to be more efficient, electrified when moving people and freight on land, based on renewable generation, and organized in such a way that guarantees very high occupancies of vehicles. All these elements will be indispensable, and even not sufficient if they are still not complemented with a reduction of mobility in absolute terms, so that economic transportation intensity—the ratio between transportation and whole economic activity—recovers to levels seen in the world four decades ago, prior to the development of present hypermobility.     

Monitoring,Warning, and Control of Rockburst in Deep Metal Mines

This paper reviews the recent achievements made by our team in the mitigation of rockburst risk. It includes the development of neural network modeling on rockburst risk assessment for deep gold mines in South Africa, an intelligent microseismicity monitoring system and sensors, an understanding of the rockburst evolution process using laboratory and in situ tests and monitoring, the establishment of a quantitative warning method for the location and intensities of different types of rockburst, and the development of measures for the dynamic control of rockburst. The mitigation of rockburst at the Hongtoushan copper mine is presented as an illustrative example.     

阀室引压管放电烧蚀失效分析

近年来,我国油气管道沿线阀室遭受的交、直流电干扰日益严重,由此引发的阀室引压管放电烧蚀问题逐渐凸显,亟需开展相关研究来弄清阀室引压管放电烧蚀的规律和机制。为此,以西气东输天然气管道某阀室引压管的放电烧蚀为例,搭建了实验室放电烧蚀平台,采用实验室模拟实验、微观分析以及现场测试相结合的方法,对该阀室引压管放电烧蚀的规律和机制进行了研究。结果表明:(1)当两根引压管间的交直流电压差大于4 V且存在接触引弧时便可以观察到明显的放电现象;(2)随着引压管间电压差和回路电流的增大,其能量升高,引压管放电烧蚀越严重;(3)直流放电烧蚀情况下阴、阳极呈现出明显不同的烧蚀形貌,阳极区烧蚀更加严重,其烧蚀坑呈现凹坑且烧蚀坑中没有明显的烧蚀产物沉积,阴极区烧蚀深度较浅,表面沉积一层烧蚀产物,而交流放电烧蚀情况下阴阳极烧蚀区域形貌基本一致,无明显差异。结论认为:该阀室的引压管放电现象是一种弧光放电,可以通过固定引压管、增大引压管间距以及阀室的交直流排流等措施来避免该现象的发生。     

Thermal performance and embodied energy analysis of a passive house – Case study of vault roof mud-house in India

This paper investigates thermal performance of an existing eco-friendly and low embodied energy vault roof passive house (or mud-house) located at Solar Energy Park of IIT Delhi, New Delhi (India). Based on embodied energy analysis, the energy payback time for the mud-house was determined as 18 years. The embodied energy per unit floor area of R.C.C. building (3702.3 MJ/m²) is quiet high as compared to the mud-house (2298.8 MJ/m²). The mud-house has three rooms with inverted U-shape roof and remaining three rooms with dome shape roof. A thermal model of the house consisting of six interconnected rooms was developed based on energy balance equations which were solved by using fourth order Runge Kutta numerical method. The predicted six room air temperatures were found in good agreement with the experimental observed data on hourly basis in each month for one year. The annual heating and cooling energy saving potential of the mud-house was determined as 1481 kW h/year and 1813 kW h/year respectively for New Delhi composite climate. The total mitigation of CO₂ emissions due to both heating and cooling energy saving potential was determined as 5.2 metric tons/year. The annual carbon credit potential of mud-house was determined as € 52/year. Similar results were obtained for the different climatic locations in India.     

Revisiting CO2 mitigation potential and costs in China’s electricity sector

To improve the reliability of sectoral mitigation potential and cost analysis, this paper made an in-depth exploration into China’s electricity sector’s thermal efficiency and inner structure. It is found that unlike what many literatures portray, China is actually among the world’s leaders in coal-fired power plants’ generating efficiencies; besides, although there are still numerous small and inefficient generating units in the current generation fleet, many of them are in fact playing important roles in supporting local economic development, meeting peak load needs, balancing heat and electricity supply and providing job opportunities to the local economy, therefore their existence does not necessarily mean low-cost mitigation potential. Given the efficiency and structural characteristics of China’s electricity sector, it is pointed out that some other mitigation options, such as demand side management, IGCC and renewable energy as well as the break-through of CCS technology may play an even more important role in emission reduction. Considering the significant lock-in effects in electricity sector, it is warned that China, if continues putting majority investment in large and advanced coal-fired generating units, will face another round of chasing-after for the new and advanced renewable generation technologies. Therefore China should put more efforts in renewable generation technologies now.     

Performance of mild steel perforated plates as a blast wave mitigation technique: Experimental and numerical investigation

This article presents the results of an experimental and numerical investigation into the influence of hole size and thickness on the performance of mild steel perforated plates as a blast wave mitigation technique. Results of the blast tests showed that the perforated plates with small hole sizes reduced the damage imparted to the target plate by reducing the target plate mid-point deflection and increasing the tearing threshold impulse. Ansys Autodyn was used to model the experiments and the perforated plate hole diameter was varied during the simulations. The impulse imparted to the pendulum, target plate and perforated plate deflections compared favourably to the experimental results. The modelling simulations also gave further insight into the interaction between the blast wave and the plates. The simulations showed that the impulse imparted to the target plate was higher than the impulse measured from the experimental pendulum swing and that the difference increased with increasing blockage ratio. The simulations also showed that the total load duration was much longer than the response time of the plate, indicating that a proportion of the impulse does not contribute to the deformation of the target plate. The response time was shown to increase with increasing blockage ratio and decrease with increasing impulse.     

Environmental and economic feasibility of palm oil biodiesel in the Mexican transportation sector

This study analyses the environmental and economic feasibility of producing palm oil-based biodiesel in Mexico in order to substitute of diesel fuel consumption using B5 until 2015 and B10 from 2016 to 2031 in the transportation sector. Two scenarios were created by projecting demand and costs for biodiesel as well as greenhouse gases emissions reduction over the next 26 years. In the environmental section, avoided emissions of Particulate matter, Total Hydrocarbons, Carbon Monoxide, Sulphur Dioxide, and Carbon Dioxide as well as the increase in Nitrous Oxide emissions were estimated for each scenario. In the economic section, a cost–benefit analysis of biodiesel substitution was implemented, and mitigation costs of Carbon Dioxide were estimated. Our results show that the feasibility of palm oil biodiesel use is directly related to the implementation of fiscal incentives, such as the exemption from tax (Special Tax on Production and Services).     

Greenhouse gas emission mitigation potential of rice husks for An Giang province, Vietnam

To evaluate the greenhouse gas (GHG) emission mitigation potential of rice husk utilization, a life cycle inventory analysis was conducted for 18 scenarios. The allocation of fuels, other than rice husks, was decided based on the current demand for and supply of rice husks. To prevent the bulky nature of rice husks, briquette production is also discussed. In the power generation scenarios, the differences between two capacities (5 MW and 30 MW) were analyzed. The results of analysis reveal that CH₄ and N₂O emissions from open burning contribute largely to the current GHG emissions. Therefore, ceasing open burning alone has a large GHG mitigation potential. The use of briquettes, even though GHG is emitted during the production stage, can still contribute to GHG emission mitigation as the production is more efficient than rice husk burning or dumping. In the power generation scenarios, most GHG emissions were derived from the combustion process. Therefore, gasification which has a little combustion process is the most efficient GHG mitigator. Both the replacement of grid electricity by generated electricity, and the replacement of diesel oil by pyrolyzed oil show larger GHG mitigation potentials than what could be derived from open burning cessation alone.     

Unequal representation of women and men in energy company boards and management groups: Are there implications for mitigation?

This survey shows that female representation in boards and management groups of large energy companies in Germany, Spain and Sweden is far from being gender-equal. Of the 464 companies surveyed, 295 (64%) had no women at all in boards or management groups and only 5% could be considered gender-equal by having 40% or more women in such positions. Interviews with energy companies confirmed current trends that gender equality efforts within decision-making in business are weak or non-existent. The findings are discussed against the background of differences in risk perceptions among women and men, evidence of women’s impact on boards and companies’ performance and the substantial risks related to unabated climate change. Research is suggested for exploring potential impacts on energy companies' performance with more women in the boards when it comes to mitigation activities.     

CARR ATWS缓解系统设计

为保证事故工况下反应堆的安全,CARR除设置保护系统外,还设置了ATWS缓解系统。本文介绍了CARR ATWS缓解系统的功能与组成以及技术特点,系统采用数字化技术,并进行了试验验证,其可靠性达到了CARR工程应用的要求。