钢铁企业二次能源综合利用

钢铁企业二次能源种类多、数量大,按特征分为可燃气体、余热、余能三类。介绍了钢铁企业二次能源产生环节及主要利用途径,通过案例对二次能源利用效益进行分析。     

Debt for brands: tracking down a bias in financing photovoltaic projects in Germany

What kinds of PV project configurations do lenders prefer to finance? Recent developments in the field of renewable energy project finance have reinforced the need for investigation, as fundraising has become more challenging and project evaluation by banks more demanding. To contribute to the limited research in this field, we focus on photovoltaic projects and report from an Adaptive Choice-Based Conjoint experiment with German experts in project finance. We find a bias which we call “debt for brands”. Simulations reveal that debt investors prefer projects with premium brand technology (modules, inverters) to low-cost technology. Although we assumed that lenders prefer projects with the highest Debt Service Cover Ratio (DSCR), they favor projects with lower DSCR, as long as those projects include premium brand technology. We find that, if premium brands were engaged, lenders would also choose projects with higher risk. Our findings have implications for renewable energy project finance in practice and research.     

The interaction between emissions trading and renewable electricity support schemes. An overview of the literature

The public promotion of electricity from renewable energy sources coexists in many countries with the recent implementation of emissions trading schemes. As shown by several papers, this coexistence may lead to significant interactions between both instruments, in the form of synergies and conflicts. This paper provides an overview and analysis of the literature on such coexistence and interactions. A major conclusion is that policy measures aiming at exploiting the synergies between both instruments should be implemented. The greatest synergy effects from the use of both instruments take place through appropriate coordination of their targets. Another key finding is that, although some stylised facts can be inferred from the studies, some results from those complex interactions are context-specific since they depend on the design of the instruments in particular countries. In spite of the significant policy implications of such interactions for the effective and cost-effective functioning of both instruments, this is a surprisingly under searched field. It is so concerning, both, theoretical and empirical analysis.

碳交易机制下可再生能源投资价值与投资时机研究

中国承诺2017年启动全国性碳排放交易系统,在碳交易机制下,可再生能源项目可以通过CCER交易获得额外收益。由于碳价格是随着市场条件而随机波动的,碳价波动性使得可再生能源发电项目投资具有了期权性质的权利,即未来不确定性可能包含更高的价值。可再生能源企业在做投资决策时,可以选择立即投资,也可以选择推迟投资,等待更多信息来提高项目收益,而立即投资的项目回报必须足够高以克服等待期权的蕴含价值。为了研究碳价波动下可再生能源项目投资,本文采用实物期权法的三叉树模型,测算了三类可再生能源发电项目投资的npv及其实物期权价值(ROV)。根据延迟实物期权决策规则,三类项目均执行期权延迟投资决策。本文还计算了在无政府补贴和有政府补贴两种情形下,三种可再生能源项目在不同时点的栏杆价格,以确定项目的投资时机。栏杆价格随着政府补贴的增加而逐步下降,说明政府补贴会促进可再生能源项目投资;栏杆价格随着时间的推移而逐步上升,意味着时间跨度越大,不确定性越大,需要更高碳市场价格来确定投资时机。本文对影响可再生能源项目投资因素敏感性进行了分析,结果表明碳价波动率与可再生能源发电项目的栏杆价格呈现正相关的关系,说明碳价波动性增加了企业投资的期权价值,却推迟了企业开展投资的时间。随着中国碳交易体系的不断完善,碳价波动幅度会趋于平稳,从而促进发电企业进行可再生能源发电项目投资。     

Environmental Security: A Geographic Information System Analysis Approach—The Case of Kenya

Studies into the relationships between environmental factors and violence or conflicts constitute a very debated research field called environmental security. Several authors think that environmental scarcity, which is scarcity of renewable resources, can contribute to generate violence or social unrest, particularly within states scarcely endowed with technical know-how and social structures, such as developing countries. In this work, we referred to the theoretical model developed by the Environmental Change and Acute Conflict Project. Our goal was to use easily available spatial databases to map the various sources of environmental scarcity through geographic information systems, in order to locate the areas apparently most at risk of suffering negative social effects and their consequences in terms of internal security. The analysis was carried out at a subnational level and applied to the case of Kenya. A first phase of the work included a careful selection of databases relative to renewable resources. Spatial operations among these data allowed us to obtain new information on the availability of renewable resources (cropland, forests, water), on the present and foreseen demographic pressure, as well as on the social and technical ingenuity. The results made it possible to identify areas suffering from scarcity of one or more renewable resources, indicating different levels of gravity. Accounts from Kenya seem to confirm our results, reporting clashes between tribal groups over the access to scarce resources in areas that our work showed to be at high risk.     

The Precautionary Principle as a Robust Cost-Effectiveness Problem

This paper offers an interpretation of the precautionary principle in terms of a safety target that a decision-maker has to reach at a minimal cost in a robust way. A two-period model is used. The precautionary principle corresponds to a situation in which the decision-maker, facing an ex ante indecision, is not able to reach a safe target from the initial condition in a worst-case framework. However, he can efficiently succeed whenever the uncertainty at the second period is revealed to him. An example coping with the management of a renewable resource illustrates the general results of the paper.

Evaluating the prospects for sustainable energy development in a sample of Chinese villages

This paper describes the methods used to evaluate the potential for achieving sustainable energy development in six Chinese villages included in the Sustainable Users' Concepts for China Engaging Scientific Scenarios (SUCCESS) Project by examining energy efficiency potential and local renewable energy prospects. The approaches needed to obtain and analyse information on possible energy efficiency measures and renewable energy resources are summarised. Results are presented in terms of cumulative net savings in primary energy consumption, as an indicator of energy resource depletion, and associated carbon dioxide emissions, as an indicator of global climate change. Options for sustainable energy development are ranked in order of likely implementation and practical actions which could be considered in each village are identified.     

Biomass production for bioenergy using recycled wastewater in a natural waste treatment system

Bioenergy production from biomass is proposed as a method to solve part of the nation's energy problem. However, biomass and bioenergy production is questioned as an environment-friendly approach due to the potential increase of water pollution and the potential decrease of available water resource. A conceptual model of an integrated natural waste treatment system that produces biogas and biomass for bioenergy, treat waste and wastewater, conserve fresh water, and decrease the potential water pollution is presented. The potential biomass production from water hyacinth, duckweed, cattail, and knotgrass was investigated using recycling wastewater from an integrated natural waste treatment system from 2005 to 2008. Although the biomass production from recycling wastewater was not controlled for maximum production, this research identified the large potential impact that could be made if these systems were implemented. The overall average water hyacinth growth rate was high to 0.297 kg wet wt./m²/day during a research period of over 500 days, including both the active and non-active growing seasons. The average daily growth rates of duckweed, cattail, and knotgrass were 0.099-0.127, 0.015, and 0.018 kg wet wt./m², respectively. This research illustrated that water hyacinth was a more promising aquatic plant biomass for bioenergy production when wastewater effluent was recycled as water and nutrient sources from an integrated natural waste treatment system.     

The Power of Bioenergy‐Related Standards to Protect Biodiversity

Abstract: The sustainable production of bioenergy is vital to avoiding negative impacts on environmental goods such as climate, soil, water, and especially biodiversity. We propose three key issues that should be addressed in any biodiversity risk‐mitigation strategy: conservation of areas of significant biodiversity value; mitigation of negative effects related to indirect land‐use change; and promotion of agricultural practices with few negative impacts on biodiversity. Focusing on biodiversity concerns, we compared principles and criteria set to address biodiversity and other environmental and social issues in seven standards (defined here as commodity‐based standards or roundtables, or relevant European legislation): five voluntary initiatives related to bioenergy feedstocks, the Renewable Transport Fuel Obligation (United Kingdom), and the European Renewable Energy Source Directive. Conservation of areas of significant biodiversity value was fairly well covered by these standards. Nevertheless, mitigation of negative impacts related to indirect land‐use change was underrepresented. Although the EU directive, with its bonus system for the use of degraded land and a subquota system for noncrop biofuels, offered the most robust standards to mitigate potential negative effects, all of the standards fell short in promoting agricultural practices with low negative impacts on biodiversity. We strongly recommend that each standard be benchmarked against related standards, as we have done here, and that efforts should be made to strengthen the elements that are weak or missing. This would be a significant step toward achieving a bioenergy industry that safeguards Earth's living heritage.     

Mesoporous simonkolleite–TiO2 nanostructured composite for simultaneous photocatalytic hydrogen production and dye decontamination

In the present work, mesoporous simonkolleite–TiO₂ composite was prepared with sol–gel method. The composite photocatalysts were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), and Raman spectroscopy. Also, surface area and particle size were analyzed using BET equation. The photocatalytic hydrogen production with simultaneous decolorization of Remazole Red (F3B) dye was investigated over TiO₂ and simonkolleite–TiO₂ composite under UV–vis light irradiation. It was worthy to be noted that the rate of hydrogen production over simonkolleite–TiO₂ is higher that produced over TiO₂. The maximum amount of photocatalytic-produced hydrogen was 2.1 mmol and 3.3 mmol within 240 min using TiO₂ and simonkolleite–TiO₂ composite, respectively. The specific production rate of hydrogen from photocatalytic conversion of dye was calculated. Improvement of apparent quantum yield (22.07%) after 5 h was achieved upon addition of simonkolleite to TiO₂. This high apparent quantum yield proves that the system proposed in this study could be a hopeful approach toward using sunlight energy as outlook energy source. The obtained results suggested that a new process for H₂ production from wastewater could be achieved. The process also provides a method for degradation of organic pollutants with simultaneous H₂ production.