Techno-Economic Optimization of Novel Stand-Alone Renewable Based Electric Vehicle Charging Station near Bahria Town Karachi,Sindh Pakistan

Electric vehicles (EVs) are the most interesting and innovative technology in the 21st century because of theirenormous advantages, both technically and economically. Their emissions rate compared to fuel-based vehicles isnegligible as they do not consume fuel and hence do not emit any harmful gases. However, their bulk production,adoption and lack of charging stations increase the stress of power stations due to modern-day lifestyles. If Electricvehicles demand increases drastically then conventional power stations will not bear their demand and if theygenerate electricity by conventional means it will be very costly and may further add greenhouse gases. Therefore,this research provides the techno-economic assessment of a stand-alone renewable-dependent electric vehiclecharging station, excluding any burden on electrical utility. The proposed study is carried out in Bahria Town,Karachi, a city in Pakistan. In this study, HOMER Pro software was utilized for techno-economic assessment. Ahybrid system comprising solar Photovoltaic/Wind Turbine/Fuel cells and battery storage is included in the model.Solar and wind resources were taken from NASA’s website, where charging stations will be integrated. The overallresults show promising in terms of total Net Present Cost and the Cost of Energy which are 2.72M $ and 0.237 $,respectively. The total system generation is 3,598 Megawatt hours per year, and the total energy consumption is 885Megawatt hours per year.

Simulation Modelling and Techno-Economics of Supercritical Carbon Dioxide Recompression Closed Brayton Cycle

In recent years, there has been global interest in meeting targets relating to energy affordability and security while taking into account greenhouse gas emissions. This has heightened major interest in potential investigations into the use of supercritical carbon dioxide (sCO2) power cycles. Climate change mitigation is the ultimate driver for this increased interest;other relevant issues include the potential for high cycle efficiency and a circular economy. In this study, a 25 MWe recompression closed Brayton cycle (RCBC) has been assessed, and sCO2 has been proposed as the working fluid for the power plant. The methodology used in this research work comprises thermodynamic and techno-economic analysis for the prospective commercialization of this sCO2 power cycle. An evaluated estimation of capital expenditure, operational expenditure, and cost of electricity has been considered in this study. The ASPEN Plus simulation results have been compared with theoretical and mathematical calculations to assess the performance of the compressors, turbine, and heat exchangers. The results thus reveal that the cycle efficiency for this prospective sCO2 recompression closed Brayton cycle increases (39% - 53.6%) as the temperature progressively increases from 550˚C to 900˚C. Data from the Aspen simulation model was used to aid the cost function calculations to estimate the total capital investment cost of the plant. Also, the techno-economic results have shown less cost for purchasing equipment due to fewer components being required for the cycle configuration as compared to the conventional steam power plant.

Numerical Modeling and Technico-Economic Analysis of a Hybrid Energy Production System for Self-Consumption: Case of Rural Area in the Comoros

This study aims to provide electricity to a remote village in the Union of Comoros that has been affected by energy problems for over 40 years. The study uses a 50 kW diesel generator, a 10 kW wind turbine, 1500 kW photovoltaic solar panels, a converter, and storage batteries as the proposed sources. The main objective of this study is to conduct a detailed analysis and optimization of a hybrid diesel and renewable energy system to meet the electricity demand of a remote area village of 800 to 1500 inhabitants located in the north of Ngazidja Island in Comoros. The study uses the Hybrid Optimization Model for Electric Renewable (HOMER) Pro to conduct simulations and optimize the analysis using meteorological data from Comoros. The results show that hybrid combination is more profitable in terms of margin on economic cost with a less expensive investment. With a diesel cost of $1/L, an average wind speed of 5.09 m/s and a solar irradiation value of 6.14 kWh/m2/day, the system works well with a proportion of renewable energy production of 99.44% with an emission quantity of 1311.407 kg/year. 99.2% of the production comes from renewable sources with an estimated energy surplus of 2,125,344 kWh/year with the cost of electricity (COE) estimated at $0.18/kWh, presenting a cost-effective alternative compared to current market rates. These results present better optimization of the used hybrid energy system, satisfying energy demand and reducing the environmental impact.

Techno-Economic Analysis of Power Production by Using Waste Biomass Gasification

Energy recovery from waste biomass can have significant impacts on the most pressing development challenges of rural poverty and environmental damages. In this paper, a techno-economic analysis is carried out for electricity generation by using timber and wood waste (T & WW) gasification in Iceland. Different expenses were considered, like capital, installation, engineering, operation and maintenance costs and the interest rate of the investment. Regarding to revenues, they come from of the electricity sale and the fee paid by the Icelandic municipalities for waste collection and disposal. The economic feasibility was conducted based on the economic indicators of net present value (NPV) and discounted payback period (DPP), bringing together three different subgroups based on gasifier capacities, subgroup a: 50 kW, subgroup b: 100 kW and subgroup c: 200 kW. The results show that total cost increases as the implemented power is increased. This indicator varies from 1228.6 k€ for subgroups a to 1334.7 k€ for subgroups b and 1479.5 k€ for subgroups c. It is worth mentioning that NPV is positive for three subgroups and it grows as gasifier scale is extended. NPV is about 122 k€ (111,020 $), 1824 k€ (1,659,840 $) and 4392 k€ (3,996,720 $) for subgroups a, b and c, respectively. Moreover, DPP has an inversely proportional to the installed capacity. It is around 5.5 years (subgroups a), 9.5 months (subgroups b) and 6 months (subgroups c). The obtained results confirm that using small scale waste biomass gasification integrated with power generation could be techno-economically feasible for remote area in Iceland.

Techno-economic analysis of single U-tube and double U-tube heat exchangers in Chongqing area

On the basis of practical projects in Chongqing,the thermal performance of heat exchangers (single U-tube type and double U-tube type) of the ground-source heat pump (GSHP) system in the hot summer was obtained and analyzed. The data obtained from test could match with the result deduced from theoretical calculation. From the test results,the cooling capacity of double U-tube is 1.6 times that of single U-tube. Taking cost per depth per watt Clq as the evaluation standard,Clq of single U-tube is 4.69 RMB$/W,and Clq of double U-tube is 3.14 RMB$/W. The double U-tube heat exchangers usage should be prioritized.

Simulation and Techno-Economic Performance of a Novel Charge Calculation and Melt Optimization Planning Model for Steel Making

Process algorithm, numerical model and techno-economic assessment of charge calculation and furnace bath optimization for target alloy for induction furnace-based steelmaking is presented in this study. The developed algorithm combines the make-to-order (MTO) and charge optimization planning (COP) of the steel melting shop in the production of target steel composition. Using a system-level approach, the unit operations involved in the melting process were analyzed with the purpose of initial charge calculation, prevailing alloy charge prediction and optimizing the sequence of melt chemistry modification. The model performance was established using real-time production data from a cast iron-based foundry with a 1- and 2-ton induction furnace capacity and a medium carbon-based foundry with a 10- and 15-ton induction furnace capacity. A simulation engine (CastMELT) was developed in Java IDE with a MySQL database for continuous interaction with changing process parameters to run the model for validation. The comparison between the model prediction and production results was analyzed for charge prediction, melt modification and ferroalloy optimization and possible cost savings. The model performance for elemental charge prediction and calculation purpose with respect to the charge input (at overall scrap meltdown) gave R-squared, Standard Error, Pearson correlation and Significance value of (0.934, 0.06, 0.97, 0.0003) for Carbon prediction, (0.962, 0.06, 0.98, 0.00009) for Silicon prediction, (0.999, 0.048, 0.999, 9E -11) for Manganese Prediction, and (0.997, 0.076, 0.999, 6E -7) for Chromium prediction respectively. Correlation analysis for melt modification (after charging of ferroalloy) using the model for after-alloying spark analysis compared with the target chemistry is at 99.82%. The results validate the suitability of the developed model as a functional system of induction furnace melting for combined charge calculation and melt optimization Techno-economic evaluation results showed that 0.98% - 0.25% ferroalloy saving per ton of melt is possible using the model. This brings about an annual production cost savings of 100,000 $/y in foundry A (medium carbon steel) and 20,000 $/y in foundry B (cast iron) on the use of different ferroalloy materials.

Techno-Economic Feasibility Analysis of Solar Photovoltaic Power Generation: A Review

With the rapid depletion of fossil fuel reserves, it is feared that the world will soon run out of its energy resources. This is a matter of concern for developing countries whose economy heavily leans on its use of energy. Under the circums-tances it is highly desirable that renewable energy resources should be utilized with maximum conversion efficiency to cope with the ever increasing energy demand. Furthermore, the global economic and political conditions that tend to make countries more dependent on their own energy resources have caused growing interest in the development and use of renewable energy based technologies. In terms of its environmental advantages, renewable energy sources generate electricity with insignificant contribution of carbon dioxide (CO2) or other greenhouse gases (GHG) to the atmosphere and they produce no pollutant discharge on water or soil and hence power generation from renewable becomes very important. Major types of renewable energy sources include solar, wind, hydro and biomass, all of which have huge potential to meet future energy challenges. Solar photovoltaic technology in one of the first among several renewable energy technologies that have been adopted worldwide for meeting the basic needs of electricity particularly in remote areas. In this paper literature review pertaining to techno-economic feasibility analysis of solar photovoltaic power generation is discussed. The literature is basically classified into the following three main category design methods, techno-economic feasibility of solar photovoltaic power generation, performance evaluations of various systems.

Techno-economic analysis of municipal wastewater land treatment systems in China

This paper analyses the capital costs, power consumption and operation costs of municipal wastewater land treatment systems, including rapid infiltration, slow-rate infiltration, overflow and constructed wetland, by means of series engineering design. The results show that land treatment can save 50-70% of capital costs, 80-90% of power and 75-85% of operation costs when compared with secondary treatment.

Techno-economical evaluation of membrane based biogas upgrading system:A comparison between polymeric membrane and carbon membrane technology

A shift to renewable energy sources will reduce emissions of greenhouse gases and secure future energy supplies. In this context, utilization of biogas will play a prominent role. Focus of this work is upgrading of biogas to fuel quality by membrane separation using a carbon hollow fibre(CHF) membrane and compare with a commercially available polymeric membrane(polyimide) through economical assessment. CHF membrane modules were prepared for pilot plant testing and performance measured using CO_2, O_2, N_2. The CHF membrane was modified through oxidation, chemical vapour deposition(CVD) and reduction process thus tailoring pores for separation and increased performance. The post oxidized and reduced carbon hollow fibres(PORCHFs) significantly exceeded CHF performance showing higher CO_2 permeance(0.021 m^3(STP)/m^2 h bar) and CO_2/CH_4 selectivity of 246(5 bar feed vs 50 mbar permeate pressure). The highest performance recorded through experiments(CHF and PORCHF) was used as simulation basis. A membrane simulation model was used and interfaced to 8.6 V Aspen HYSYS.A 300 Nm^3/h mixture of CO_2/CH_4 containing 30-50% CO_2 at feed pressures 6, 8 and 10 bar, was simulated and process designed to recover99.5% CH_4 with 97.5% purity. Net present value(NPV) was calculated for base case and optimal pressure(50 bar for CHF and PORCHF). The results indicated that recycle ratio(recycle/feed) ranged from 0.2 to 10, specific energy from 0.15 to 0.8(kW/Nm^3 feed) and specific membrane area from 45 to 4700(m^2/Nm^3 feed). The high recycle ratio can create problems during start-up, as it would take long to adjust volumetric flow ratio towards 10. The best membrane separation system employs a three-stage system with polyimide at 10 bar, and a two-stage membrane system with PORCHF membranes at 50 bar with recycle. Considering biomethane price of 0.78 $/Nm^3 and a lifetime of 15 years, the technoeconomic analysis showed that payback time for the best cascade is 1.6 months.

Modifying Plant Oils for Use as Fuel in Rural Contexts Tanzania: Techno-Economic Analysis

Techno-economic analysis of a small-scale Modified Plant Oil (MPO) production plant that has an annual production capacity of 15,072,741 kg of MPO (batch process) was carried out to estimate the capital and operating costs of a plant. The analysis was done by using a computer model that was designed and simulated with an aid of SuperPro Designer (Version 4.32) software. The specified feedstock was crude Jatropha oil (JO) and the main product was MPO. The major processes involved were degumming, neutralisation and blending. Degumming involved the removal of gums or phospholipids, and two methods were used: water degumming and acid degumming, whereas blending involved mixing of degummed or purified JO with natural gas condensate (NGC) modifier to lower the viscosity of JO. From techno-economic analysis of the process, it was found that the total capital investment of a plant was about US $ 10,222,000 and the predicted unit production cost of MPO was US $ 1.315/kg at a value of US $ 1.0/kg of JO. The economic feasibility of MPO production was found to be highly influenced by the price of feedstock, which contributed about 95% of the total annual production cost. The relationship between plant throughput and unit cost of producing MPO showed that unit production cost was very sensitive to production rate at low annual throughputs. The MPO cost showed a direct linear relationship with the cost of JO, with a change of US $ 0.50/kg of MPO in MPO cost in every change of US $ 0.50/kg of JO in JO price. The process technology simulated was found to be economically viable and can be implemented in rural setting, taking into consideration Tanzania’s rural situation.

Identification of Techno-Economically Viable Crop Residue Utilization in India

India generates more than 140 million tonnes of surplus crop residue every year In Haryana, the agricultural sector alone produces 24.64 million tonnes of residue annually;of which only 71% is consumed in various domestic and commercial activities within the state. The rest of the material is burned causing severe contamination of air with smoke. There is an urgent need to identify suitable and sustainable conversion technologies that are efficient, eco-friendly as well as cost-effective for managing the huge available biomass not only in the state but also in the country. This paper reviews briefly the available crop residue and quantities burned, proposes a scheme to incorporate part of the residue in the field for its fertilizer value. The remaining biomass is harvested for animal feed and the excess is converted to bioenergy and biofuels. Among the developed and developing biofuels, the paper identifies biogas production from biomass for on-farm use. Pelletization is identified as an enabling technology to provide high quality feedstock for conversion to heat/power and in near future to advanced biofuels.

数字技术创新驱动新兴产业成长的路径选择与政策取向

新兴产业根植于技术创新,技术创新引发产业变革,催生新兴产业。数字经济背景下,新一轮数字技术革命正在发生,为新兴产业的成长提供了通用技术支撑和组织原则。数字技术创新作用于市场需求、技术创新环境以及高效运作的组织原则三种因素,进而驱动新兴产业成长。随着数字技术的深化应用,数字鸿沟、数字技术创新成果转化能力弱、产业组织形态更新缓慢等问题制约了数字技术创新驱动作用的发挥。因此,数字技术创新驱动新兴产业成长路径,应通过弥合数字鸿沟、支持数字产业创新发展、推动产业组织形态更新三条路径,畅通数字技术创新驱动新兴产业成长的障碍。在数字技术创新驱动新兴产业成长的政策层面,为有效发挥数字技术创新驱动新兴产业成长的作用,在产业支持政策的制定过程中应遵循竞争友好原则,发挥市场机制的选择作用,不断完善财税与金融支持政策,推动数字平台治理创新。

技术封建主义:文化霸权的新向度

技术封建主义是西方学界最近提出的一种理论话语,它力图对当下以互联网、大数据、云计算、人工智能等为表征的资本主义新状况进行阐释。学界对此的研究主要集中在经济和政治层面,而对于其文化影响则未有阐述。在新技术条件下,技术封建主义题旨已然溢出单纯的经济疆域和政治边界,广泛地渗透到当代社会生活的方方面面。在此语境中,技术封建主义的文化逻辑主要在知识垄断和大数据操控两个层面展开:一方面,通过窃取或掠夺而来的知识,文化霸权得到极大的巩固和加强;另一方面,通过大数据下的信息推送,根据大他者的欲望而结构起来的主体欲望得到了空前的关注和放大。由此,文化霸权以一种全新的样态给主体带来了前所未有的影响和规约。

Techno-Economic and Sustainability Analysis of Potential Cooling Methods in Irish Data Centres

11% of Irish electricity was consumed by data centres in 2020. The Irish data centre industry and the cooling methods utilised require reformative actions in the coming years to meet EU Energy policies. The resell of heat, alternative cooling methods or carbon reduction methods are all possibilities to conform to these policies. This study aims to determine the viability of the resell of waste heat from data centres both technically and economically. This was determined using a novel application of thermodynamics to determine waste heat recovery potential in Irish data centres, and the current methods of heat generation for economical comparison. This paper also explores policy surrounding waste heat recovery within the industry. The Recoverable Carnot Equivalent Power (RCEP) is theoretically calculated for the three potential cooling methods for Irish data centres. These are air, hybrid, and immersion cooling techniques. This is the maximum useable heat that can be recovered from a data centre rack. This study is established under current operating conditions which are optimised for cooling performance, that air cooling has the highest potential RCEP of 0.39 kW/rack. This is approximately 8% of the input electrical power that can be captured as useable heat. Indicating that Irish data centres have the energy potential to be heat providers in the Irish economy. This study highlighted the technical and economic aspects of prevalent cooling techniques and determined air cooling heat recovery cost can be reduced to 0.01 €/kWhth using offsetting. This is financially competitive with current heating solutions in Ireland.

技术世中教育的加速隐忧及其超越

人类世描绘着人与自然的“脱嵌”,其典型特征是人类以技术手段过度征用自然,造成自然的不断熵增。同时,人类世还表征着以人工智能为核心的现代技术对“自然人”的技术改造,构成现代性加速危机。人类世是技术世,亦是教育世。当前,教育被裹挟进技术世的“加速逻辑”中,教育时空在加速博弈中走向结构异化;在对技术加速的迷恋之中,学生的自由发展与精神世界被辖制,师生整体性地陷入了行动“倦怠综合征”,教育的本真意义在加速中迷失了方向。为超越技术世给教育带来的加速困境,教育仍需基于生命本真重塑教育的时空结构;在寻求凝思、敞开自我、回归现实的过程中寻求教育的积极行动;最终在人机共鸣之中重塑教育的意义,实现“技术—人—自然—社会—世界”的融合构筑。

“经济-生态-社会”系统下的绿色经济创新

结合WSR系统论及技术经济范式理论分析绿色经济创新的“经济-生态-社会”系统特征,构建绿色经济创新指数评价体系并基于中国30个省份2011—2020年数据进行评价。研究表明,第一,绿色经济创新是以技术、产品及解决方案等为底座,在新旧技术差距的引导下,注重生态环境,强调社会组织管理模式的演进及需求实现,表现为经济范式创新、生态范式创新和社会范式创新;第二,经济系统是绿色经济创新的关键,系统内数字、绿色及生物等技术能够催生一系列绿色产品及智慧方案,但社会和生态系统能反过来促进经济系统的创新。实证结果显示中国绿色经济创新指数的历年发展出现双“U”型特征,2013年和2019年分别拐点,并且在时空演变上呈现“强者恒强,弱者恒弱”的特征。研究为厘清技术变革背景下绿色经济创新的运行机制及关键要素,为我国绿色经济创新发展提供系统参考。

基于零排的高盐废水处理技术经济比选分析

高盐废水零排工艺中常有超滤、反渗透、MVR蒸发等工艺的组合,但因为零排的水平衡问题,其组合顺序影响投资规模和运行成本。以某资源化项目的废水零排处理工艺为例,对不同的工艺路线进行技术经济分析,研究发现直接采用MVR蒸发全量处理废水能耗过高,采用DTRO减量化后再蒸发结晶更经济,分析成果可为类似项目决策提供参考。

技术复杂性与信息技术知识普及对任务绩效的影响机制:一个有调节的中介模型

数字化技术的发展改变了员工的办公环境,在提高办公效率的同时也可能产生技术压力等负面影响。本研究以多个中小高科技企业的443名中基层员工为研究对象,基于工作要求—资源理论,构建了一个有调节的中介模型,针对性地探讨了技术压力来源因素中的技术复杂性和技术压力抑制因素中的信息技术知识普及如何对任务绩效产生影响,并探索了多个边界条件。实证研究结果表明,一方面,工作倦怠在技术复杂性和任务绩效之间起到中介作用,且技术自我效能感和信息技术知识普及分别负向调节该中介效应;另一方面,工作投入在信息技术知识普及和任务绩效之间也起到中介作用,且技术自我效能感和技术复杂性分别正向调节该中介效应。本研究从组织和员工的双重角度探索了技术复杂性及其针对性缓解策略对任务绩效的抑制与强化机制,揭示了数字化办公情境下员工所面临技术复杂性的影响机制和应对办法,为技术压力挑战下的员工绩效改善提供有益启示。

技术—经济范式赶超机遇与中国国家创新体系建设转型:概念框架、日本经验与启示

[目的/意义]本文从技术—经济范式理论视角把握后发经济体摆脱“追赶—落后—追赶”路径依赖,实现赶超与国家创新体系建设转型的关系,为中国在新发展阶段有效抓住新一轮技术—经济范式变革机遇、提升国家创新体系效能提供依据和思路。[方法/过程]首先,构建技术—经济范式赶超与国家创新体系建设的概念框架;然后,分析日本促进技术—经济范式超越追赶的国家创新体系建设取向;最后,辨析当前中国与日本实现技术—经济范式赶超面临的情境异同,指出中国国家创新体系建设转型的方向。[结果/结论]“导入期”和“转折期”是后发经济体实现技术—经济范式超越追赶中的关键进程,需要国家创新体系给予有效的制度、组织及资源支持。日本经验对中国国家创新体系转型有4点启示:兼顾范式追赶和范式引领两个有着本质性差异的目标,重视但不拘泥于突破核心关键技术,重点围绕潜在优势产业布局及一体化政策配套转型,以及着重思考如何借助海外投资提升中国企业的国际竞争能级。

技术民族主义及其对美国对华科技政策的塑造

随着科学技术成为大国博弈的核心领域,技术民族主义在美国再次兴起。美国技术民族主义有着鲜明的美国特质,表现为“美国至上”的优越感、“边疆主义”的扩张性、“唯我独尊”的排他性和“臆造敌人”的非理性。美国技术民族主义的实质是技术霸权主义,它通过作用于大众对国际环境的感知和解读,塑造对华认知,开展国内动员,深刻影响着美国对华科技政策的目标和手段。美国对中国信息通信业的打压生动诠释了美国技术民族主义的作用机制:臆造中国相关产业威胁美国国家安全,丑化中国企业形象,制造不实舆论,滥用立法、行政、司法手段,拉拢裹挟盟友共同对华施压。面对中国科技的加速追赶,以维护霸权为根本目的的美国技术民族主义将在相当长时期内发挥影响,这将进一步加剧大国竞争和地缘政治对抗。