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1.
Renewable energy is worldwide seen as a key element necessary to address climate change. However, finding socially acceptable locations for renewable energy facilities and the accompanying infrastructure increasingly often faces fierce opposition. This paper quantifies the landscape externalities of renewable energies employing a choice experiment. In addition, it is investigated how accounting for non-compensatory choice behavior, i.e. attribute cut-offs, affects welfare measures and subsequently policy recommendations. The empirical application is Germany where we conducted a nationwide survey on the development of renewable energies. We first show that cut-off elicitation questions prior to the choice experiment at least partially influence preferences. We further find that most participants state cut-off levels for attributes. Many are, however, at the same time willing to violate the self-imposed thresholds when choosing among the alternatives. To account for this effect, stated cut-offs are incorporated into a mixed logit model following the soft cut-off approach. Model results indicate substantial taste heterogeneity in preferences and in the use of cutoffs. Also, welfare estimates are substantially affected. We conclude that welfare changes from renewable energy development could be strongly underestimated when cut-offs are ignored.  相似文献   
2.
[目的]休闲观光农业建设是绍兴市产业转型升级的关键一步,探寻休闲观光农业新模式,能够为休闲农业发展提供理论参考。[方法]文章采用变异系数法确定指标权重,多因素综合分析法测算观光农业发展水平,从循环经济角度出发,评价2001—2016年绍兴市休闲观光农业发展可持续性,提出发展中存在的问题并探索循环型的休闲观光农业新模式。[结果](1)2001—2016年以来,经济发展可持续性得分较高,资源环境可持续得分次之,循环经济可持续发展偏低。(2)现阶段绍兴市休闲观光农业发展主要存在休闲观光农业自然环境不断遭到破坏,休闲观光农业缺乏整体规划,休闲观光农业旅游支撑体系不够健全等问题。(3)未来发展中,循环经济发展下的休闲观光农业可以开发建设时空复合循环型、资源综合利用循环型、能量多级利用循环型、综合开发利用循环型等4种模式。[结论]未来绍兴市应将循环经济的理念融入到休闲观光农业中,因地制宜,科学选择循环型休闲观光农业发展模式; 规划先行,科学利用农业旅游资源; 强化保障,建立休闲观光农业支撑体系,全面推动休闲观光农业健康持续发展。  相似文献   
3.
This study investigates the importance of mindfulness‐based organization systems and policies on the organization's continuous efforts to become a greener company. The study is devised as a pooled cross‐sectional time series analysis of productivity in energy consumption, water utilization, and waste generation and recycling of U.S. companies. The data set taken from U.S. Newsweek 500 recorded 600 companies dispersed into 63 industries during the period of 2012–2014 and provided 1,498 company–industry–year observations. The study found that systems and policies (e.g., deployment of third‐party auditors for its environmental metrics report; linkage of the remuneration of company's senior executive team with the achievement of environmental performance targets; and establishment of a committee at the Board of Directors' level whose mandate includes sustainability of the company in environment‐ and resource‐related matters) connect the company's mindfulness to its effort in improving the environmental quality through the company's productivity in energy consumption, water utilization, and waste generation and recycling. The relationships are positive and significant. Also, systems and policies serve as a motivator for the firm to continue to improve upon the current achievements. The study emphasizes the importance of translating organizational and individual mindfulness into organization policies and systems in order to motivate the organization to continuously improve its productivity in energy consumption, water utilization, and waste generation and recycling leading to improvements in environmental quality.  相似文献   
4.
针对斜坡堤越浪量预测方法,分别建立集成神经网络(ensemble neural network,ENN)、随机森林(random for-eset,RF)和支持向量回归机(suppport vector regression,SVR)3种机器学习模型对斜坡堤越浪量进行预测,并利用决定系数R2和均方根误差RMSE来评估模型性能.最后,对3种模型的性能进行分析.结果显示,集成神经网络模型的决定系数R2和均方根误差RM S E分别约为0.96和0.0018,随机森林模型的决定系数R2和均方根误差RMSE分别约为0.97和0.0014,支持向量回归机模型的决定系数R2和均方根误差RMSE分别约为0.94和0.002.对比发现,3种模型的决定系数都达到0.9以上,都具有较高的预测精度,随机森林相比其他两个模型精度更高.  相似文献   
5.
Improving access is a priority in the offshore wind sector, driven by the opportunity to increase revenues, reduce costs, and improve safety at operational wind farms. This paper describes a novel method for producing probabilistic forecasts of safety-critical access conditions during crew transfers. Methods of generating density forecasts of significant wave height and peak wave period are developed and evaluated. It is found that boosted semi-parametric models outperform those estimated via maximum likelihood, as well as a non-parametric approach. Scenario forecasts of sea-state variables are generated and used as inputs to a data-driven vessel motion model, based on telemetry recorded during 700 crew transfers. This enables the production of probabilistic access forecasts of vessel motion during crew transfer up to 5 days ahead. The above methodology is implemented on a case study at a wind farm off the east coast of the UK.  相似文献   
6.
This paper examines whether luxury products can support a circular economy. This is done through a literature review of luxury products and the links to circular economy, as well as a case study of Bang & Olufsen (B&O). The literature review revealed links between some of the core characteristics of luxury products and the circular economy. This included aspects such as the high quality, durability, service schemes, extended warranties, and large aftermarkets. The case study supports the links between the inner circles in the circular economy (maintenance, repair, and reuse) and some of the core characteristics of luxury products. B&O produces products with a long lifespan, has extended warranties, repair and service schemes, spare part availability for 8 years, an aftermarket, and leasing schemes. B&O also does reconditioning of components for its repair loop, conducts dismantling tests, marks plastic parts, and has a negative list that excludes certain hazardous components.  相似文献   
7.
王蕾 《科技和产业》2019,19(8):49-53
梳理国内外动力和储能电池产业发展情况,从产业规模、重点企业、产业链、培养方向等角度剖析了泰州市动力和储能电池产业的现状问题,并针对性地提出了发展建议。  相似文献   
8.
Improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To do this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed.  相似文献   
9.
Reducing dependence on fossil fuels by decreasing energy consumption is a common environmental policy. One mechanism used to achieve this is to encourage increased energy efficiency. However, improving efficiency may have an opposing effect and cause an increase in energy consumption if the intensity of use changes. This phenomenon is known as the rebound effect. We estimate direct rebound effects for energy use in Australia based on both aggregate residential energy use data and on household energy expenditure data. Our approach implements a new methodology developed by Hunt and Ryan (2014, Catching on the rebound: Why price elasticities are generally inappropriate measures of rebound effects. Surrey Energy Economics Discussion Paper Series SEEDS 148; 2015, Energy Economics 50, 273) that explicitly relates energy service use with energy source demand and directly incorporates measures of efficiency changes. The results indicate that the rebound effect is relatively high for energy use by Australian households. Due to the unique nature of our household data set, we can examine the influence of demographic and housing characteristics. We find that low‐income households and households with vulnerable members have the largest rebound effects. The relatively large rebound effects found here suggest that consumers gain from efficiency by improved energy services, and thus, policy targeting energy efficiency is not likely to be successful at reducing energy consumption.  相似文献   
10.
以浙江电网企业转型现代能源综合服务的具体战略与发展规划为研究背景,针对能源综合服务系统的运行规划目标,开展基于运行规划的能源综合服务系统能效管理研究。从系统工程的视角出发,以能源流为纽带,基于多尺度能源系统建模方法,构建了能源综合服务系统模型,并结合系统综合能效,采用粒子群优化算法来优化系统各设备单元的运行策略,以实现基于运行规划的最优能效管理。通过能源综合服务系统模型计算表明,大规模清洁能源和可再生能源的接入,可以明显提高系统综合能效;随着区域用户总冷量和/或总热量需求占总电力需求的比值增大,系统最优综合能效逐渐增大;与使用内燃机、燃气轮机及汽轮机为原动机的热电联产系统相比,使用燃料电池为原动机的热电联产系统可以使能源综合服务系统综合能效更优。  相似文献   
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