Renewable energy resources and technologies in Nigeria: present situation, future prospects and policy framework

Nigeria is endowed with abundant energy resources, both conventional and renewable, whichprovide her with immense capacity to develop an effective national energy plan. However, introduction of renewable energyresources into the nation's energy mix have implications on itsenergy budget. The national energy supply system has been projected intothe future using MARKAL, a large scale linear optimization model.However, this model may not be absolutely representative of the highlynon-linear future of renewable energy. Results of the model reveal that under onlya least cost constraint, only large hydro power technology is the prominentcommercial renewable energy technology in the electricity supply mix of thecountry. Despite the immense solar energy potentials available, solar electricity generation is attractive only under severeCO2 emissions mitigation of the nation's energy supply system. Similarly, the penetration of small-scale hydro power technology in theelectricity supply mix is favoured only under CO₂ emissionsconstraints. Due to economy of scale, large hydropower technology takes the lion share of all the commercial renewableenergy resources share for electricity generation under any CO₂emissions constraint. These analyses reveal that some barriers exist to thedevelopment and penetration of renewable energy resources electricity production in Nigeria's energy supplysystem. Barriers and possible strategies to overcome them arediscussed. Intensive efforts and realistic approachtowards energy supply system in the country will have to be adopted inorder to adequately exploit renewable energy resources and technologiesfor economic growth and development.     

考虑能源结构和气候因素的电动汽车温室气体影响

电动汽车因在使用过程中近似零排放而被认为是节约能源和减少碳排量的有力工具.但我国的电力结构是以火力发电为主,这会使电力在生产阶段排放大量的二氧化碳.为进一步研究电动汽车的环境友好性,本文构建了一种改进的电动汽车排放指数模型,使用2017年的电网统计数据及气候统计数据,就能源结构和气候这两个关键因素对我国31个省市分区域展开实证研究.结果表明,电动汽车对温室气体产生的影响存在明显的空间变化,且其与能源结构中火力发电占比密切相关.另外,对于全年温度变化范围较宽的省市,气候因素可能是使电动汽车和燃油车的碳排量达到排放平衡点的关键因素.基于此,扩大电力结构中清洁能源使用比例、改善电池性能、完善相关政策体制是促进今后我国电动汽车清洁、低碳发展的重要途径.     

Feasibility of husk-fuelled steam engines as prime mover of grid-connected generators under the Thai very small renewable energy power producer (VSPP) program

Rice husk generated as a by-product of rice mill processes can be utilized as an energy source for husk-fuelled rice mills. The economic evaluation of the investment of husk-fuelled steam engine rice mills, which generate mechanical energy for the direct driving of milling equipments, has previously been presented in literature. It was reported that for some particular conditions of rice mill, the investment of husk-fuelled steam engine as energy-saving technology is financially feasible. Since May 2002, electricity distributors in Thailand have allowed renewable energy producers up to 1 MW to connect their generators to the grid in order to sell surplus electricity to the grid. This arrangement creates more income opportunities for husk-fuelled steam engine owners to generate not only mechanical power for rice milling processes, but also surplus electricity for feeding onto the grid. The objective of this study is to investigate the financial feasibility of the investment in a husk-fuelled steam engine system which drives grid-connected electrical generators, reduces rice mill demand and electricity and sells surplus electricity to the grid. The technical and economic data for rice mill sizes 35, 45, 60, 95 and 120 t/d presented in this study show that the husk-fuelled steam engine system with grid-connected generators improves the economic performance of applying the system solely for the largest 120 t/d rice mills. However, the conventional husk-fuelled steam engine without electric generator gives a better economic performance of the rice mills sizes from 45 to 95 t/d.     

A strategic design approach to develop sustainable product service systems: examples taken from the ‘environmentally friendly innovation’ Italian prize

The product service systems’ (PSS) sustainability potential is described in the framework of the new types of stakeholder relationships and/or partnerships, producing new convergence of economic interests, and a potential concomitant systemic resources optimization.In this perspective, it is argued that the design competencies should move towards those of the ‘strategic design’, thus introducing the concept of ‘strategic design for sustainability’: the design of an innovation strategy, shifting the business focus from designing (and selling) physical products only, to designing (and selling) a system of products and services which are jointly capable of fulfilling specific client demands, while re-orienting current unsustainable trends in production and consumption practices.Some examples of PSS are presented and discussed using the PSS categories ‘services providing added value to the product life cycle’, ‘services providing final results to customers’, and ‘services providing enabling platforms for customers’. The cases derive from an analysis of the ‘environmental friendly innovation’ yearly endowed prize submissions. The Politecnico di Milano University together with the Bocconi University and Legambiente (an environmental NGO) promotes the initiative in Italy.     

Brazil's Electric Power Choices and Their Corresponding Carbon Emissions Implications

This study analyzes the options for meeting power demand in the Brazilianpower sector through the year 2015. Three policy cases are constructedto test economic and environmental policy measures against a baseline:advanced technologies scenario, environmental control scenario and carbon(C) elimination scenario. Least-cost modeling simulated these scenarios throughchanges in emissions fees and caps, costs for advanced technologies,demand side efficiency, and clean energy supplies. Results show that, in theabsence of alternative policies, new additions to Brazil's electric powersector will shift rapidly from hydroelectricity to combined-cycle natural gasplants. When the cost of environmental impacts are incorporated in theprice of power, the least-cost mix of electric power generation technologycould change in other ways. In all scenarios, energy efficiency andcogeneration play an important role in the least-cost power solution. Savingelectricity through increased efficiency offsets the needs for new supply andhas enormous potential in Brazil's industrial sector. Efficiency also reducesthe environmental burden associated with electricity production andtransmission, without compromising the quality of the services demandedby end users. Interesting enough, carbon dioxide (CO₂) emissions will remainrelatively low under almost every conceivable scenario.     

中国居民能源价格扭曲的家庭消费效应

以电力能源为研究对象,选取2014—2018年中国家庭追踪调查(CFPS)与能源价格扭曲指标的匹配数据,从微观家庭层面经验考察了居民能源价格扭曲对家庭消费的影响及其作用机制。结果表明:(1)普遍存在负向扭曲的居民电力价格提升了居民家庭消费水平,特别是增加了居民家庭的电能、食品、衣着鞋帽、设备及日用品、交通通信、文教娱乐及其他分项消费支出。(2)居民能源价格扭曲通过收入效应与互补效应影响居民家庭消费水平及其结构。(3)居民能源价格扭曲的家庭消费效应在城乡家庭之间、城乡各收入组家庭之间存在异质性。居民能源价格扭曲对农村家庭消费水平的促进作用比城镇家庭更大,同时,居民能源价格扭曲对城乡家庭消费的促进作用都体现在提高各自高收入组家庭消费。这些结论可为推进能源市场化改革并建立公平与效率兼容的能源价格机制提供决策参考。     

Survey of willingness of residents to participate in electronic waste recycling in Nigeria – A case study of mobile phone recycling

Presently, large quantities of waste mobile phones are being generated in Nigeria with a significant proportion in storage. This paper investigated the behavior of consumers in Nigeria towards this waste stream and their willingness to participate in waste mobile phones recycling. This study also assessed the willingness of consumer's to pay for a more ‘environment friendlier’ phone – the so-called ‘green phone’. We performed a principal component analysis with varimax rotation in order to condense some of our questions into a smaller set of factors. We developed a model to estimate and explain the willingness to pay (WTP) a premium for ‘green’ cell phones. The model showed that the significant predictors of willingness to pay extra for green electronics include awareness and concern about the deteriorating environment, age, and the general attitude towards the environment. About 65% of the respondents are either ‘willing’ or ‘very willing’ to drop-off no-longer-in-use electronics at a nearby recycling facility. Majority of the respondents are also very willing to pay a premium for a green phone. Considering the increasing waste generation by this sector, it has become expedient that a recycling program be introduced for these potentially harmful waste materials.     

Comparative studies on the soil life in ecofarmed and conventionally farmed fields and grasslands of Austria

The soil fauna of ecofarmed and conventionally farmed fields and grasslands was investigated in various regions of Austria. The results obtained from the evaluation of a total of 13 paired sites are reviewed in this contribution: (1) many of the investigated soil zoological parameters do not differ statistically in ecofarmed and conventionally farmed fields and grasslands; (2) there are no striking differences in species composition and dominance structure of the protozoa, an important group of indicator organisms due to their delicate external membranes, their short generation time and their high contribution to energy flow and nutrient cycling; (3) all differences which can be guaranteed with an error probability of α = 10% or less invariably show higher biological activity in the ecofarmed plots. The soil physical and chemical investigations which accompanied the zoological studies on some sites indicate that the higher biological activity is caused by the higher humus content and the lower soil compaction. The organic matter content is significantly higher in the ecofarmed plots, whereas soil compaction is more pronounced under conventional cultivation; (4) conventional agriculture has a more detrimental effect on soil fauna in semi-arid regions without stockfarming than in atlantic regions with mixed husbandry. A short review of the literature shows our results to be consistent with those of other studies. It is increasingly evident that generalizations like ‘Conventional farming destroys life in the soil’ or ‘Ecofarming stimulates soil life’ are only partially supported by the available data. A far more comprehensive view taking into account especially climate, soil type and farm management is necessary. However, the discernible detrimental effects on the soil organisms caused by conventional farming call for serious consideration and ought to stimulate the development of soft agricultural technology and intensified soil biological research. Future research should include studies on productivity of soil animals under various management systems, the analysis of single factors (e.g. the special admixtures used in biodynamic farming) to elucidate causative mechanisms, and studies on the relationship between soil animals, crop production and sustained yield.     

重污染天气下电力行业排放对京津冀地区PM2.5的贡献

利用CAMx(区域空气质量模型)中的PSAT(颗粒物源示踪技术),分析了重污染天气下分区域、分行业的污染物排放对京津冀地区PM_2.5的贡献,设计了分行业排放的环境影响效率系数(EESCR)计算方法,并对“电能替代”(以电力行业产能替代民用能源消耗)情景方案下的排放进行模拟分析. 结果表明:在重污染天气背景下,电力行业排放对京津冀地区ρ(PM_2.5)的贡献率较低,各地均低于10%,并且区域排放的贡献次序为京津冀以外地区>京津冀其他城市>当地,这与电力行业高架源排放的特征有关,而工业和民用行业对区域排放的贡献次序相反. PM_2.5主要组分和前体物的分行业EESCR计算结果表明,电力行业ESSCR值均在y=1/2x趋势线之下,远低于其他行业,因此优先控制其他行业排放才是改善京津冀地区空气质量的关键.电能替代的情景模拟结果表明,电能替代是有效降低京津冀地区ρ(PM_2.5)的可行方式. 研究显示,充分利用电力行业高架源排放的特点和便于集中处理的行业优势,尽力降低因产能增长带来的排放增量,实施电能替代可成为改善区域空气质量的有效途径之一.      

气象、本地光化学生成和外围传输对长沙市2018～2020年臭氧污染趋势变化影响的识别

针对湖南省臭氧(O₃)污染加剧但是相关的研究较为缺乏的现状,以长沙市为研究区域,基于观测数据,结合气象校正、基于经验的模型(EOF)和绝对得分受体模型(APCs),识别量化了2018～2020年气象、本地光化学生成和外围传输对O₃污染相对贡献的影响,分析了2018～2019年和2019～2020年O₃趋势变化的主控因素.结果表明,短期范围内,气象条件是O₃污染事件发生的重要诱发因素.对长沙市整体来说,在时间上,2018～2019年期间,气象和本地前体物排放影响作用的增强是O₃浓度升高的关键驱动因子.2019～2020年期间,气象、本地前体物排放和外围传输影响均呈现下降的趋势,是导致O₃浓度降低的重要影响因素.空间上,2018～2020年时间段,气象、本地前体物排放和外围传输主要影响区域分别为长沙市偏东、偏北和偏南部区域.其中,外围传输的作用持续减弱,2018～2019年期间,长沙市北部天然源排放水平的升高使得O₃浓度上升,南部区域NO...     

轻型纯电动汽车生产和运行能耗及温室气体排放研究

基于中国本地化的环境负荷数据,建立了电动汽车全生命周期模型,深入分析和评估了电动汽车生产和运行两个阶段的能耗及温室气体排放(Greenhouse gases,GHGs).结果表明:电动汽车生产和运行过程的总能耗为474 GJ;GHGs为40500 kg(以CO2当量计),电动汽车生产和运行过程的GHGs分别占总排放量的23.5%和76.5%.对于电动汽车生产过程能耗和GHGs而言,原材料生产均为主要贡献者,GHGs占到车辆生产过程的74.6%,占生命周期的17.5%.另外,情景分析表明,再生材料应用、单位电力GHGs和百公里电耗能够在很大程度上影响电动汽车的碳排放.再生金属替代原生金属后,从情景1到情景5,车辆生产的GHGs下降了约22.2%,车辆生产和运行过程的总GHGs下降了约4.7%;单位电力GHGs每下降1%,电动汽车运行GHGs下降0.9%;电动汽车百公里电耗每下降1.0%,车辆生产和运行过程总GHGs下降约1.0%.因此,发展清洁能源、降低火力发电比例、优化原材料生产工艺、提高再生原材料用量等,是有效降低电动汽车全生命周期过程总能耗和GHGs的重要途径.     

基于GREET的纯电动公交车与传统公交车全生命周期评估

随着纯电动公交车在城市公共交通中应用越来越广泛,需要对纯电动公交车和传统柴油公交车进行全生命周期评估,并分析推广纯电动公交的可行性.通过美国阿贡实验室开发的GREET（greenhouse gases,regulated emissions,and energy use in transportation model）软件,充分考虑油井-油泵、公交车运行、车身系统制造、液体系统制造、ADR（装配、报废和回收质量）以及电池制造等6个阶段能耗,结合公交车车型信息和路况信息,构建公交模型,并对公交模型进行能耗模拟、排放物模拟和经济效益评估.结果表明,若车身长度为12 m,车身质量为18 t时,纯电动公交车运行过程能耗仅占其总能耗的31.1%.相较于传统公交车,纯电动公交车全生命周期能耗减少29.1%,全生命周期内VOC、CO、NO_x等污染物排放量分别减少8.7%、36.7%、50.2%,温室气体CO₂的排放量减少19.7%.若公交车队规模为20辆,纯电动公交车使用年限为8 a,则纯电动公交车比例需超过12.7%才能实现盈利,单辆纯电动公交车若实现盈利至少需要3 a.      

The role of social, political, and economic interests in promoting state green electricity policies

State governments in the United States have adopted a number of policies to encourage the production of electricity from “green” energy sources. While these state-level policies have been shown to stimulate green electricity development, the rate at which such policies have been adopted by the states differs significantly. This paper examines the potential influence of a state's particular social, political, and economic interests on its propensity to adopt green electricity policies. We use an empirical model that combines various social, political and economic indicators as explanatory variables of a state's likelihood to adopt four specific green electricity policies: renewable portfolio standards, net metering rules, public benefits funds, and generation disclosure rules. Using binary logistics regressions, the results suggest that social interests, measured by the level of income, the level of education, and the degree of participation in environmental lobbying groups, are positively linked to the adoption of green electricity policies. Similarly, political interests as measured by the pro-environment voting by states’ representatives in the U.S. Congress, also play a positive role in the adoption of such policies.     

Estimation of probabilities and likely consequences of a chain of accidents (domino effect) in Manali Industrial Complex

Chains of accidents (the domino effect) have been occurring with ever increasing frequency in chemical process industries. This is reflected in several accidents ‘J Loss Prevent Process Ind 12 (1999a) 361’; the world's worst industrial accident of the 1990s — the Vishakhpatnam disaster — also involved the domino effect ‘J Loss Prevent Process Ind 12 (1999a) 361; and Process Safety Prog 18 (1999b) 135’. Such chains of accidents have a greater propensity to cause damage than stand-alone accidents ‘Process Safety Prog 17(2) (1998a) 107; and J Loss Prevent Process Ind 12 (1999a) 361’.In order to assess the likelihood of occurrence of the domino effect and its damage potential, use of deterministic models in conjunction with probabilistic analysis is required. Recently we have proposed a systematic methodology called ‘domino effect analysis’ (DEA). A computer-automated tool, DOMIFFECT, has also been developed by us based on DEA ‘Process Safety Prog 17(2) (1998a) 107; Environment Model Software 13 (1998b) 163; and Risk assessment in chemical process industries: advanced techniques. Discovery Publishing House (1998c)’.This paper illustrates the application of DEA and DOMIFFECT to an industrial complex comprising 16 different industries. Out of 12 credible accident scenarios envisaged in three different industries — namely Madras Refineries Limited (MRL), UB Petrochemicals (UBP) and Indian Organic Chemicals Limited (IOCL), eight scenarios are likely to cause the domino effect. A further detailed analysis reveals that accidents in the storage of liquified petroleum gas and propylene and in the reflux drum units of MRL may cause domino effects. Similarly, propylene storage of UBP and monoethylene glycol storage of IOCL are also likely to cause domino effects. The impact of various chains of accidents has been forecast which reveals that in several cases the accidents may be catastrophic, harming the entire industrial complex of 16 industries. The study leads to the identification of ‘hot spots’ — units that pose the greatest risk — in turn forewarning the industries concerned and enabling them to prioritize and augment accident-prevention steps.     

基于中国电网结构及一线典型城市车辆出行特征的PHEV二氧化碳排放分析

中国电网火电比例的空间差异与插电式混合动力汽车（PHEV）驱动能源的二元性增加了研究PHEV二氧化碳排放的复杂性.使用上海市50辆PHEV汽车13万km的数据,研究了基于PHEV实际运行数据的二氧化碳排放评估方法,分析了PHEV纯电驱动里程比例及其影响因素,获得了纯电续驶里程、充电频率、电网构成对PHEV二氧化碳排放强度的影响,展望了2020年PHEV技术水平的二氧化碳减排效果.结果表明,我国一线城市PHEV乘用车出行主要集中在50 km以内的范围,占日常出行频次的70%;在2016年全国平均电网结构下,续驶里程超过50 km的PHEV比传统燃油车少排放15%以上的二氧化碳;在高比例可再生能源电网结构的地区,PHEV碳排放可降至100.0 g·km^-1以下,相比平均电网结构下碳排放水平降低幅度在28%以上;在2016年平均电网结构及技术水平下,纯电续驶里程增加（50~100 km）、充电频率增加（0.5~2次·d^-1）对碳排放的改善幅度不明显;与2016年相比,2020年PHEV燃油经济性和电耗水平的改善可降低32%的碳排放.     

Cost efficiency analysis and emission reduction by implementation of energy efficiency standards for electric motors

The industrial sector is the biggest electricity consumer in Malaysia. Electric motors account for more than 45% of the electricity consumption in the industrial sector in the country. Therefore, it is very important to implement energy efficiency standards for electric motors to reduce energy consumption growth in this sector. This paper attempts to calculate the cost efficiency analysis and emission reduction by implementing energy efficiency standards for electric motor in Malaysia. The energy efficiency standards are proposed based on the efficiency of electric motors from survey data. The study examines the potential energy, economical and environmental impacts of the implementation of energy efficiency standards for electric motors in three scenarios i.e. 0.5%, 1.0% and 1.5% of standards efficiency improvement. Standards also enable consumers to reduce their electricity bill and contribute to a positive environmental impact.     

高空核电磁脉冲对爆炸箔起爆器安全性的影响

目的评估爆炸箔起爆器(EFI)在高空核电磁脉冲下的安全性。方法通过吉赫兹横电磁波室(GTEM)强电磁脉冲模拟系统,开展辐射方式下EFI电极塞在模拟高空核电磁脉冲(HEMP)下的感应电流试验测试。HEMP主要是通过电磁辐射方式在EFI脚线上耦合能量,在爆炸箔上产生感应电流,用光纤场强计监测模拟HEMP的电场强度,并在EFI爆炸箔电极塞脚线上套装电流环,通过示波器监测爆炸箔上的感应电流波形。结果在爆炸箔电极塞两根脚线上分别连接相同长度的导线,按导线长度不同分为5、10、20、30、40、50 cm共6组,使导线成180°状态,EFI的脚线可等效为偶极天线,感应电流随脚线长度增加而增大,两者呈线性关系。结论 EFI在HEMP下的感应电流远小于发火电流,对核电磁脉冲环境具有较高的耐受能力,具有较高的安全性。     

江苏省电力发展与环境变化的灰色关联分析研究

文章以灰色关联分析的理论与方法为基础,分别将江苏全省SO2排放量、工业烟（粉）尘排放量、工业废气排放量和工业固体物产生量作为因变量参考数列,江苏省地区生产总值、发电总量、火力发电量、火力发电量占发电总量比重作为比较数列,对电力发展与环境变化进行综合分析,结果表明火力发电对环境变化影响较大.因此,积极发展新能源发电项目,扩大新能源发电比重,降低火力发电比重,构建合理的能源结构成为江苏省环境保护的重中之重.     

基于太阳能驱动的有机废气冷凝和吸附回收系统的经济评价

介绍了基于太阳能光伏发电-蓄电池直流供电、集成冷凝法和吸附法的有机废气回收系统。对整个系统进行经济评价,得出该回收系统在其寿命周期内可节约23.07万元左右的电费,但其静态投资回收期为6.1年,大于常规的交流电驱动的油气回收系统的回收期,这是因为太阳能光伏发电系统的造价偏高。如果量产后,预期装置的回收期降为3.01年,小于常规的回收系统。     

Assessment of renewable energy potential and policy in Turkey – Toward the acquisition period in European Union

This paper aims to assess the renewable energy capacity of Turkey in order to consider main priorities in the energy policy of Turkey. In this paper, renewable energy potential and regulatory conditions are discussed in Turkey in comparison with European Union. The results of the study implemented within the framework of EnviroGRIDS project indicated a promising yet very susceptible future for the implementation of renewable energy power plants in Turkey. The forecasts have shown that the solar power potential utilization is becoming more significant after 2020. The projections for 2050 indicate that electricity consumption from small and medium renewable energy sources including solar and wind will constitute 15% of the total, whereas the solar thermal will constitute around 16%. Geothermal and other renewables will remain around 3%. According to the high demand scenario, in 2050 the share of hydropower in overall electricity generation will be 12%, followed by solar power at 7% and wind power at 3%. Additionally, renewable energy policy and regulations in Turkey and in EU are overviewed in this study. On the contrary to EU, the constant feed-in tariff amount does not consider capital investments of specific energy sources in Turkey that brings disadvantage to the implementation. However, new regulations published and currently applied should be accepted as milestones in acquisition period of Turkey in EU.