Global energy and emissions scenarios for effective climate change mitigation—Deterministic and stochastic scenarios with the TIAM model

The achievement possibilities of the EU 2 °C climate target have been assessed with the ETSAP TIAM global energy systems model. Cost-effective global and regional mitigation scenarios of carbon dioxide, methane, nitrous oxide and F-gases were calculated with alternative assumptions on emissions trading. In the mitigation scenarios, an 85% reduction in CO₂ emissions is needed from the baseline, and very significant changes in the energy system towards emission-free sources take place during this century. The largest new technology groups are carbon-capture and storage (CCS), nuclear power, wind power, advanced bioenergy technologies and energy efficiency measures. CCS technologies contributed a 5.5-Pg CO₂ annual emission reduction by 2050 and 12 Pg CO₂ reduction by 2100. Also large-scale forestation measures were found cost-efficient. Forestation measures reached their maximum impact of 7.7 Pg CO₂ annual emission reduction in 2080. The effects of uncertainties in the climate sensitivity have been analysed with stochastic scenarios.     

MODELING THE EFFECTS OF VARIABLE ANNUAL FLOW ON RIVER CHANNEL MEANDER MIGRATION PATTERNS,SACRAMENTO RIVER,CALIFORNIA, USA1

ABSTRACT: Flow regulation impacts the ecology of major rivers in various ways, including altering river channel migration patterns. Many current meander migration models employ a constant annual flow or dominant discharge value. To assess how flow regulation alters river function, variable annual flows ‐ based on an empirical relationship between bank erosion rates and cumulative effective stream power ‐ were added into an existing migration model. This enhanced model was used to evaluate the potential geomorphic and ecological consequences of four regulated flow scenarios (i.e., different hydrographs) currently being proposed on the Sacramento River in California. The observed rate of land reworked correlated significantly with observed cumulative effective stream power during seven time increments from 1956 to 1975 (r²= 0.74, p = 0.02). The river was observed to rework 3.0 ha/yr of land (a mean channel migration rate of 7.7 m/yr) with rates ranging from 0.8 ha/yr to 5.1 ha/yr (2.0 to 13.3 m/yr), during the analyzed time periods. Modeled rates of land reworked correlated significantly with observed rates of land reworked for the variable flow model (r²= 0.78, p = 0.009). The meander migration scenario modeling predicted a difference of 1 to 8 percent between the four flow management scenarios and the base scenario.     

Tri-generation investment analysis using Bayesian network: A case study

The increasing energy demand, increasing energy dependency, energy supply security, and environmental concerns have become a part of business policies since COP21 agreements in Paris, 2015. Combined cooling, heating, and power (CCHP or tri-generation) systems play an important role in paying the necessary attention to these policies. Tri-generation investment is a complex decision with hybrid use of energy resources. This article aims to reduce the complexity of this decision by the use of Bayesian belief networks in pre-investment stage of tri-generation investment project cycle. The proposed model gives an insight into decision analysis and helps the decision-makers either generate or purchase from it in order to meet the energy demand with different scenarios. The model is studied for a university case. The investment decision for a CCHP (tri-generation) system will be discussed as an alternative for purchasing the electricity and natural gas from the national grids.     

Analysis of energy security and sustainability in future low carbon scenarios for Brazil

This study estimated a series of indicators to assess the energy security of supply and global and local environmental impacts under different mitigation scenarios through 2050 in Brazil, designed with the integrated optimization energy system model MESSAGE‐BRAZIL. The assessment of interactions between environmental impacts and energy security dimensions was complemented through the application of life cycle assessment (LCA) methodology. Overall results imply energy security establishes more synergies than trade‐offs in increasingly stringent mitigation scenarios, especially patent within the sustainability dimension, which increases energy security and provides additional benefits regarding climate change mitigation and air pollution emissions. It is still necessary to extend analysis to other energy sectors in addition to the power supply sector and to promote a better understanding of repercussions of energy scenario expansion in energy security.     

Sizing and performance analysis of standalone hybrid photovoltaic/battery/hydrogen storage technology power generation systems based on the energy hub concept

In this study, the optimal sizing and performance analysis of a standalone integrated solar power system equipped with different storage scenarios to supply the power demand of a household is presented. One of the main purposes when applying solar energy resource is to face the increasing environmental pollutions resulting from fossil fuel based electricity sector. To this end, and to compare and examine two energy storage technologies (battery and hydrogen storage technology), three storage scenarios including battery only, hydrogen storage technology only and hybrid storage options are evaluated. An optimization framework based on Energy Hub concept is used to determine the optimum sizes of equipment for the lowest net present cost (NPC) while maintaining the system reliability. It was determined that the most cost effective and reliable case is the system with hybrid storage technology. Also, the effects of solar radiation intensity, the abatement potential of CO₂ emissions and converting excess power to hydrogen on the system’s performance and economics, were investigated and a few noticeable findings were obtained.     

中国煤电企业环境压力测试

中国煤电行业的发展伴随着各种环境风险,本文以典型煤电企业为例,在产能过剩、能效标准提高、环境保护税、全国碳市场、水资源税和非水可再生能源规划目标的风险约束下,建立环境成本内部化和环境风险分析工具,考虑不同压力情境下对煤电企业价值的影响,构建环境风险影响财务成本的压力测试框架。结果表明,对单个风险而言,产能过剩和碳市场风险对企业价值的影响是大多数地区在不同情景中面临的主要风险驱动因素。对于综合风险压力测试而言,各地区1 000MW超超临界机组乐观情景及悲观情景的企业价值距合理回报预期企业价值相差小,而300MW和600MW亚临界机组因能效水平低、经营成本高等原因在环境风险压力下企业价值偏离合理回报较多。随着环境风险严重程度的不断增加,环境压力测试有助于煤电企业和金融机构了解环境风险对企业财务状况的影响,从而对投资决策产生影响。     

Causal interactions between environmental degradation,renewable energy,nuclear energy and real GDP: a dynamic panel data approach

Renewable energy as well as nuclear energy are low carbon power that presents the life cycle emissions of greenhouse gases than fossil fuel energy. However, analyzing the relationship between the consumption of renewable energy, consumption of nuclear energy, CO₂ emissions and economic growth is crucial for the economic and energy policy decision; we address this question for developed countries. This paper deals with the relationships between nuclear energy, environmental degradation, real GDP and renewable energy. We apply a panel data model for a global panel consisting of nine developed countries during the period 1990–2013. The group studied consists of Canada, France, Japan, Netherlands, Spain, Sweden, Switzerland, UK and the USA. The empirical findings suggest that: (1) a causal link between emissions and real income, (2) a unidirectional causality running from renewable energy to nuclear energy, (3) a unidirectional causal relationship running from capital to environmental degradation, (4) a unidirectional causal relationship running from income to nuclear energy consumption, since the growth hypothesis is valid, (5) a unidirectional causality running from capital to income, (6) no an outstanding role of renewable energy use in the contribution of CO₂ emissions.     

Constructing land-use maps of the Netherlands in 2030

The National Environmental Assessment Agency of the RIVM in the Netherlands is obliged to report on future trends in the environment and nature every 4 years. The last report, Nature Outlook 2, evaluated the effects of four alternative socio-economic and demographic scenarios on nature and the landscape. Spatially detailed land-use maps are needed to assess effects on nature and landscape. The objective of the study presented here was how to create spatially detailed land-use maps of the Netherlands in 2030 using the Environment Explorer, a Cellular Automata-based land-use model to construct land-use maps from four scenarios. One of these is discussed in great detail to show how the maps were constructed from the various scenario elements, story lines and additional data and assumptions on national, regional and local land-use developments. It was the first time in the history of our outlooks that consistent, spatially detailed land-use maps of the Netherlands for 2030 were constructed from national economic and demographic scenarios. Each map represents a direct reflection of model input and assumptions. The maps do not show the most probable developments in the Netherlands but describe the possible change in land use if Dutch society were to develop according to one of the four scenarios. The large (societal) uncertainties are reflected in the total set of future land-use maps. The application of a land-use model such as the Environment Explorer ensures that all relevant aspects of a scenario, i.e. economic and demographic developments, zoning policies and urban growth, are integrated systematically into one consistent framework.     

A multi-criteria framework to assess the sustainability of renewable energy development in the Alps

A multi-criteria analysis (MCA) was implemented to assess the best solutions for enhancing the production of renewable energy in the Alps. A set of criteria were selected based on the impacts of four renewable energy sources (forest biomass, hydropower, ground solar photovoltaic and wind power) on the three spheres of sustainability (environmental, social and economic). Three different scenarios are presented, each with a different set of weights for the criteria: the first scenario considers equally all three aspects of sustainability; the second scenario foresees an environmentally-oriented perspective, while the third scenario is more focused on the socio-economic aspects related to the development of renewable energy. Results show that forest biomass and hydropower seem to be the most viable solutions for enhancing the share of renewable energy in the Alps. Ground solar photovoltaic and wind power, on the other hand, seem to be less attractive alternatives due to their high impacts on land use.     

Multicriteria Relocation Analysis of an Off-site Radioactive Monitoring Network for a Nuclear Power Plant

Due to increasing environmental consciousness in most countries, every utility that owns a commercial nuclear power plant has been required to have both an on-site and off-site emergency response plan since the 1980s. A radiation monitoring network, viewed as part of the emergency response plan, can provide information regarding the radiation dosage emitted from a nuclear power plant in a regular operational period and/or abnormal measurements in an emergency event. Such monitoring information might help field operators and decision-makers to provide accurate responses or make decisions to protect the public health and safety. This study aims to conduct an integrated simulation and optimization analysis looking for the relocation strategy of a long-term regular off-site monitoring network at a nuclear power plant. The planning goal is to downsize the current monitoring network but maintain its monitoring capacity as much as possible. The monitoring sensors considered in this study include the thermoluminescence dosimetry (TLD) and air sampling system (AP) simultaneously. It is designed for detecting the radionuclide accumulative concentration, the frequency of violation, and the possible population affected by a long-term impact in the surrounding area regularly while it can also be used in an accidental release event. With the aid of the calibrated Industrial Source Complex–Plume Rise Model Enhancements (ISC-PRIME) simulation model to track down the possible radionuclide diffusion, dispersion, transport, and transformation process in the atmospheric environment, a multiobjective evaluation process can be applied to achieve the screening of monitoring stations for the nuclear power plant located at Hengchun Peninsula, South Taiwan. To account for multiple objectives, this study calculated preference weights to linearly combine objective functions leading to decision-making with exposure assessment in an optimization context. Final suggestions should be useful for narrowing the set of scenarios that decision-makers need to consider in this relocation process.     

AN ANALYSIS OF WATER RESOURCES CONSTRAINTS ON POWER PLANT SITING IN THE MID-ATLANTIC STATES1

ABSTRACT: Expansion of the electrical generation system in the Pennsylvania-Jersey-Maryland power pool will impact, and be constrained by, inland water availability. Future interpretations of the Federal Water Pollution Control Act Amendments of 1972 regarding evaporative cooling towers for coastal power plants, offshore siting and energy centers, and the policies and public acceptability of low flow augmentation reservoirs are some of the issues examined in this paper using scenarios generated by the Brookhaven National Laboratory Regional Energy Facility Siting Model (REFS). REFS is a multicommodity, transshipment-location linear programming model used here to allocate power plants among counties in a power pool under a minimization of cost objectives. The solutions are sensitive to the water resources assumptions in the model. For the year 2000, the amount of low flow augmentation allowed in the region's river basins and whether off-shore siting becomes a reality are the two water resources related issues which most affect the scenarios. The results show that decisions regarding specific water problems can have region wide implications for water and nonwater related issues.     

Attitudes to nuclear energy: Beliefs,values and false consensus

Attitudinal differences regarding the use of nuclear energy were investigated. Results obtained in a random sample drawn from the population of four communities in The Netherlands within 30 miles of a nuclear power plant showed a strong relationship between subjects' attitudes towards nuclear energy and their perceptions of the possible consequences of nuclear energy. ‘Pro’- and ‘con’-subjects showed marked differences in the importance attached to the different possible consequences and their endorsement of the salience of more general social issues. Results provide support for the view that individuals perceive a false consensus with respect to the relative prevalence of similar attitudes among other people. Finally, subjects' perceptions of others with similar or opposing attitudes towards the issue of nuclear energy showed marked differences in evaluation especially for the extreme attitude groups.     

Quantifying the Impact of Renewable Energy Futures on Cooling Water Use

This article presents an empirically based model, WiCTS ( Wi thdrawal and C onsumption for T hermoelectric S ystems), to estimate regional water withdrawals and consumption implied by any electricity generation portfolio. WiTCS uses water use rates, developed at the substate level, to predict water use by scaling the rates with predicted energy generation. The capability of WiCTS is demonstrated by assessing the impact of renewable electricity generation scenarios on water use in the United States (U.S.) through 2050. The energy generation scenarios are taken from the Renewable Energy Futures Study performed by the U.S. National Renewable Energy Laboratory of the U.S. Department of Energy. Results indicate reductions in water use are achieved under these renewable energy scenarios. The analysis further explores the impact of two modifications to the modeling framework. The first modification presumes geothermal and concentrated solar power generation technologies employ water‐intensive cooling systems vs. cooling technology that requires no water. The second modification presumes all water‐intensive cooling technologies use closed cycle cooling (as opposed to once‐through cooling) technologies by 2050. Results based on one of the renewable generation scenarios indicate water use increases by over 20% under the first modification, and water consumption increases by approximately 40% while water withdrawals decrease by over 85% under the second modification.     

The impact of climate change on the benefit of a rain barrel sharing network

The assessment of the impact of climate change depends not only on quantitative changes in precipitation but also system characteristics that can be changed and enhanced. This study investigated the effect of building the shared network of a rainwater harvesting system as an adaptation to climate change scenarios. The performance of a rain barrel network under three climate change scenarios and three global circulation models (GCM) is examined. A sample community composed of four prospective users with individual storage is tested with various forms of shared connections. Most importantly, the results show that the benefit from shared rain barrels greatly increases under the climate change conditions compared with the historical rainfall data. Especially, for high reliabilities, the results indicate that the benefit of a rain barrel network increases under future climate change scenarios, whereas it does not show apparent improvement for low reliabilities. However, the performance of a rain barrel network is highly dependent on location and climate change scenarios. In contrast, the GCM does not considerably affect the performance of the shared network. The results of this study highlight the needs to establish sharing networks of rainwater harvesting systems under the climate change conditions, which would significantly increase the benefit of the entire community.     

Environmental evaluation of plastic waste management scenarios

The management of the plastic fraction is one of the most debated issues in the discussion on integrated municipal solid waste systems. Both material and energy recovery can be performed on such a waste stream, and different separate collection schemes can be implemented. The aim of the paper is to contribute to the debate, based on the analysis of different plastic waste recovery routes. Five scenarios were defined and modelled with a life cycle assessment approach using the EASEWASTE model. In the baseline scenario (P0) the plastic is treated as residual waste and routed partly to incineration with energy recovery and partly to mechanical biological treatment. A range of potential improvements in plastic management is introduced in the other four scenarios (P1–P4). P1 includes a source separation of clean plastic fractions for material recycling, whereas P2 a source separation of mixed plastic fraction for mechanical upgrading and separation into specific polymer types, with the residual plastic fraction being down-cycled and used for “wood items”. In P3 a mixed plastic fraction is source separated together with metals in a “dry bin”. In P4 plastic is mechanically separated from residual waste prior to incineration.A sensitivity analysis on the marginal energy was carried out. Scenarios were modelled as a first step assuming that marginal electricity and heat were based on coal and on a mix of fuels and then, in the sensitivity analysis, the marginal energy was based on natural gas.The study confirmed the difficulty to clearly identify an optimal strategy for plastic waste management. In fact none of the examined scenarios emerged univocally as the best option for all impact categories. When moving from the P0 treatment strategy to the other scenarios, substantial improvements can be obtained for “Global Warming”. For the other impact categories, results are affected by the assumption about the substituted marginal energy. Nevertheless, irrespective of the assumptions on marginal energy, scenario P4, which implies the highest quantities of specific polymer types sent to recycling, resulted the best option in most impact categories.     

Why Singapore's land transportation energy consumption is relatively low

Since the early 1970s, Singapore has enacted a number of measures to tackle traffic congestion, including measures to restrain vehicle ownership. Although Singapore's per capita GDP is comparable to that of OECD countries, the present car-ownership level in Singapore (10 cars per 100 people) is only a fraction of levels in the OECD countries. Traffic flow in this city-State is relatively smooth, even during peak hours. Although the measures taken were aimed primarily at tackling traffic congestion, they have had other positive impacts, such as reducing energy consumption, air pollution and CO₂ emissions. This article presents an overview of the transportation measures and initiatives in Singapore, and analyses two of the transport demand management measures in detail: the vehicle restraint measure, in particular the unique vehicle quota system introduced in 1990; and the two road pricing systems, i.e. the area licensing scheme (ALS) that operated from 1974 to 1998, and the electronic road pricing system (ERP) that went into operation in 1998. Energy and environmental impacts are then discussed, and finally factors contributing to the success of these schemes. Although certain conditions are unique to Singapore, the experience shows that substantial energy and environmental benefits can be achieved through managing urban transportation system in an integrated and innovative way.     

Local energy governance in post-Fukushima Japan: a survey of citizen willingness to participate in local energy policy deliberations

Employing a social survey, this paper examines citizen attitudes towards local energy governance in the aftermath of the Great East Japan Earthquake and the subsequent nuclear power plant accident. The survey found that public comment and random sampling citizen deliberation led to a greater willingness to participate in discussions of municipal heating and power (energy) policy for a resilient community than did conventional citizen committee membership. The former mechanisms provided opportunities for individuals with considered viewpoints to participate in a public dialogue on energy and environment issues in post-disaster Japan. Respondents who did not have clear ideas about a roadmap for nuclear power generation showed a lower willingness to participate in local energy policy formulation processes.     

Environmental impact evaluation of feeds prepared from food residues using life cycle assessment

There is increasing concern about feeds prepared from food residues (FFR) from an environmental viewpoint; however, various forms of energy are consumed in the production of FFR. Environmental impacts of three scenarios were therefore investigated and compared using life cycle assessment (LCA): production of liquid FFR by sterilization with heat (LQ), production of dehydrated FFR by dehydration (DH), and disposal of food residues by incineration (IC). The functional unit was defined as 1 kg dry matter of produced feed standardized to a fixed energy content. The system boundaries included collection of food residues and production of feed from food residues. In IC, food residues are incinerated as waste, and thus the impacts of production and transportation of commercial concentrate feeds equivalent to the FFR in the other scenarios are included in the analysis. Our results suggested that the average amounts of greenhouse gas (GHG) emissions from LQ, DH, and IC were 268, 1073, and 1066 g of CO(2) equivalent, respectively. The amount of GHG emissions from LQ was remarkably small, indicating that LQ was effective for reducing the environmental impact of animal production. Although the average amount of GHG emissions from DH was nearly equal to that from IC, a large variation of GHG emissions was observed among the DH units. The energy consumption of the three scenarios followed a pattern similar to that of GHG emissions. The water consumption of the FFR-producing units was remarkably smaller than that of IC due to the large volumes of water consumed in forage crop production.     

A CLOSED WATER REUSE SYSTEM FOR POWER PLANT COOLING AND DIGESTER HEATING1

ABSTRACT: A model consisting of closed water reuse and productive use of various types of wastes for energy generation is presented. The sewage after treatment would be used as the cooling water for power plants, and the condenser discharge therefrom be used as heating water for sludge digesters. The water is then purified for municipal water supply for continuous use. The advantages of this system are that water resources and energy are conserved while various types of wastes including waste heat are controlled. With a preliminary system analysis, it appears that the design for power plant based on the total heating value of wastes and digester capacity based on sewage sludge generation is feasible in terms of acquisition and full utilization of various types of wastes as generated in a single metropolitan area. The system as shown in this design is in balance among various factors such as the generation rate of municipal refuse, municipal sewage, waste heat in the condenser discharge, and raw sewage sludge.