Transport, energy and global climate change

Energy has been remarkably cheap, and the community has come to believe that the supply of energy is completely reliable. The low cost of energy is reflected in the design of transport systems and cities. In the near future, energy is likely to become very expensive and less reliable, and at the same time there is growing concern about the environmental damage created by fossil fuels. This study examines the impact of those changes, and considers how future cities can be redesigned to account for it. It argues that redesign could minimise the role of the private car, and that at the same time cities would become more pleasant and more interesting.     

Transport,energy and global climate change

Energy has been remarkably cheap, and the community has come to believe that the supply of energy is completely reliable. The low cost of energy is reflected in the design of transport systems and cities. In the near future, energy is likely to become very expensive and less reliable, and at the same time there is growing concern about the environmental damage created by fossil fuels. This study examines the impact of those changes, and considers how future cities can be redesigned to account for it. It argues that redesign could minimise the role of the private car, and that at the same time cities would become more pleasant and more interesting.     

住宅建筑气候适应性优化设计研究

以中国5个典型城市的气候条件为例，提出住宅建筑气候适应性优化设计流程。基于Grasshopper参数化性能分析平台，和Ladybug/Honeybee环境分析插件，以热环境舒适度模型、建筑能耗模型和建筑生命周期成本模型为目标函数进行优化分析。发现哈尔滨和北京气候条件下，住宅建筑应选择nZEB'（权衡最优）设计参数，而上海、昆明和深圳气候条件下，C-O（成本效益最优）解决方案比nZEB（节能最优）解决方案的综合效益更好。基于参数化性能模拟的多目标优化可以有效辅助住宅建筑的气候适应性设计研究。     

生态水景——规划设计是关键

许多城市的滨水景区既是视线焦点,也是公共区,景观设计应致力将其打造成可持续的生态水景,而不是常规的高耗能、高成本养护的水景设计,景观设计应兼顾可达性、实用性、生态性、参与性和公平性,其中以生态性尤为重要,营造生态水景可以从植物、驳岸设计和意境营造3个方而着手.以北京地区的京杭大运河北京通州段、北京温愉河生态走廊(朝阳段)和昆玉河生态水景走廊的设计为例解读城市生态廊道的营造实践.     

Economical assessment of different HVAC systems for an operating room: Case study for different Turkish climate regions

In this study, the annual energy consumptions of four different heating, ventilation and air conditioning (HVAC) systems serving to operation rooms (ORs) located at five different cities (Izmir, Antalya, Istanbul, Ankara and, Erzurum) in Turkey are analyzed. The study is performed for four different HVAC systems: (a) 100% fresh air system (System I), (b) 100% fresh air with half air volume rate at night period (System II), (c) 100% fresh air with half air volume rate at night period and heat recovery unit (System III), (d) 50% fresh air with half air volume rate at night period and with heat recovery and mixing units (System IV). Life cycle cost (LCC) for 20 years life span is calculated for the considered systems. It is found that System IV considerably reduces energy consumption and it is economically proper for the considered cities. The rate of energy consumption and LCC reductions are greater for the cities with extreme climate condition having relatively low specific humidity ratio. Using System IV instead of System I reduces OR energy consumption by 74% for the city of Erzurum which has a cold and dry climate.     

Life-cycle carbon and cost analysis of energy efficiency measures in new commercial buildings

Energy efficiency in new building construction has become a key target to lower nation-wide energy use. The goals of this paper are to estimate life-cycle energy savings, carbon emission reduction, and cost-effectiveness of energy efficiency measures in new commercial buildings using an integrated design approach, and estimate the implications from a cost on energy-based carbon emissions. A total of 576 energy simulations are run for 12 prototypical buildings in 16 cities, with 3 building designs for each building-location combination. Simulated energy consumption and building cost databases are used to determine the life-cycle cost-effectiveness and carbon emissions of each design. The results show conventional energy efficiency technologies can be used to decrease energy use in new commercial buildings by 20-30% on average and up to over 40% for some building types and locations. These reductions can often be done at negative life-cycle costs because the improved efficiencies allow the installation of smaller, cheaper HVAC equipment. These improvements not only save money and energy, but reduce a building’s carbon footprint by 16% on average. A cost on carbon emissions from energy use increases the return on energy efficiency investments because energy is more expensive, making some cost-ineffective projects economically feasible.     

Benefit‐cost analysis of commercially available activated carbon filters for indoor ozone removal in single‐family homes

This study involved the development of a model for evaluating the potential costs and benefits of ozone control by activated carbon filtration in single‐family homes. The modeling effort included the prediction of indoor ozone with and without activated carbon filtration in the HVAC system. As one application, the model was used to predict benefit‐to‐cost ratios for single‐family homes in 12 American cities in five different climate zones. Health benefits were evaluated using disability‐adjusted life‐years and included city‐specific age demographics for each simulation. Costs of commercially available activated carbon filters included capital cost differences when compared to conventional HVAC filters of similar particle removal efficiency, energy penalties due to additional pressure drop, and regional utility rates. The average indoor ozone removal effectiveness ranged from 4 to 20% across the 12 target cities and was largely limited by HVAC system operation time. For the parameters selected in this study, the mean predicted benefit‐to‐cost ratios for 1‐inch filters were >1.0 in 10 of the 12 cities. The benefits of residential activated carbon filters were greatest in cities with high seasonal ozone and HVAC usage, suggesting the importance of targeting such conditions for activated carbon filter applications.     

浅谈小城镇建设工程造价管理的控制措施

通过对小城镇建设工程造价管理存在问题的分析,提出了从法制健全和完善方面加强小城镇建设工程造价管理的措施,指出小城镇建设工程造价管理的核心在于合理确定和有效控制工程造价,目的在于提高工程效益。     

北方居住建筑综合修正系数的研究

研究了屋顶、地面、山墙耗热量和冷风渗透耗热量对热用户耗热量的影响，引入综合修正系数对热量表计量值加以修正，使热费合理分摊。以15栋住宅建筑物为对象，研究了北方5个城市综合修正系数随建筑朝向、地区、节能率和建筑物体形系数的变化规律。     

国内几种供暖方式的经济技术比较与分析

对以燃料为能源供暖、电热供暖以及热泵采暖方式等几种供暖方式的优缺点、经济性、应用前景进行比较和分析，提出在目前国内能源结构状态下，如从环境保护和热能利用角度出发，热电联产集中供热将是大城市供热的首选方式；对于既要供暖又要空调的场所，地源热泵在目前能源价格下具有很强的经济竞争力；对于供暖终端设备，地板辐射采暖系统同普通散热器采暖系统成本基本持平，但节能效果显著。     

Analyzing barriers of Smart Energy City in Accra with two-step fuzzy DEMATEL

The prevalence of Smart Energy City (SEC) has over the years been seen as a preemptive measure in dealing with many energy problems faced by cities. Like other cities, Accra faces several barriers on its way to achieve SEC. This research seeks to identify possible barriers hindering Accra as a city from becoming a SEC and prioritizing these barriers based on both importance with consideration of interactions between barriers using a two-step Decision Making, Trial and Evaluation Laboratory under fuzzy set environment i.e. two-step fuzzy DEMATEL. For Accra, the results indicate that market barriers are the most important barriers while limited access to capital has the highest global importance score in the whole SEC barriers system. Besides, technology barriers, policy barriers and market barriers are found as cause barriers and high cost of technology dispatches more impact on other barriers in technology barriers category. High interest rate and unstable currency, inadequate infrastructure requiring huge investments, insufficient legal and regulatory framework, high cost of technology and lack of information about cost and benefits of renewable energy technology are deserved to be paid more attention since they have both high important and cause indexes. The result is to enhance strategic decision making since this combination of methods deals with the possible human sentiments in decision making and also organizes barriers into cause and effect groups based on their interactions, with the cause groups been critical since their presence can give rise to effect group barriers.     

The cost of controlling crime: A study in economies of city life

Conclusions Sizeable economies and diseconomies of size exist with regard to a given quality of police protection. Our results show that the per capita social cost of crime declines slowly with larger cities until a low point is reached in cities with a population ranging from 250, 000 to 500, 000. Social costs rise sharply for cities of over 1 million inhabitants. By and large, the smaller cities are able to reduce their crime rates with an increase in police numbers while the larger cities fail to do so based on evidence from time series analysis. Thus our results underestimate the social cost of crime in large cities even though they show the cost to be lower in small cities than in large cities. The results suggest that policies of decentralization rather than increasing police rates may be the most cost-effective long-run solution to high crime rates in large cities. Recommendation of a policy, however, awaits a more definitive analysis of costs of other services by city size.Journal Article 2110 of the Agricultural Experiment Station, Oklahoma State University, Stillwater. This research was supported in part by the National Science Foundation. Dean Schreiner and Gerald Doeksen contributed several suggestions which improved this study.     

A study on the optimum insulation thicknesses of building walls with respect to different zones in Morocco

Morocco has very limited indigenous energy resources; consequently, with the increase in energy consumption over the last years, studies focusing on energy saving as well as usage of sustainable energy resources have accelerated. However, in Morocco the buildings have an important part in the energy consumption; therefore, the most logical solution is energy saving by using thermal insulation. For this purpose, in this study, six cities, namely Agadir, Tangier, Fez, Ifran, Marrakech and Errachidia are selected to represent the six zones of Morocco. Using the life-cycle cost analysis method, the optimum insulation thicknesses as well as energy savings and payback periods for electricity tariff and three different types of insulation material have been determined.     

欠发达的中小城市多层住宅更节能

通过对住宅的成本构成进行分析,以多层和高层两种不同建筑结构类型住宅在建造成本、使用功能、投资效果、物业管理、居住安全5个方面进行分析对比,总结出在中小城市建造设计多层比高层更具有科学化、人性化、经济化的优点,体现了节能方面的重要性.高层建筑在建造和使用时的能耗都很高,提示我们在设计上应重视建筑结构类型,多层住宅建筑是在欠发达的中小城市的理想节能住宅类型.     

Analysis of mobile home thermal performance

Various levels of investment in energy-efficient designs for new mobile homes are examined. The purpose is to define relationships between annual energy use for space heating and air conditioning and additional investment in the structure shell. These relationships are developed for nine different cities in the U.S.A.The optimal design configuration (in the sense of minimum life cycle cost) is determined for mobile homes in each city as a function of the energy use/cost relationship, heating fuel choice, climate, fuel prices, and other economic factors. Results of this analysis indicate that the 1976 thermal standard promulgated by the Department of Housing and Urban Development (HUD) requires considerably less investment in energy-efficient design than the optimal for all but the warmest climates. The present HUD standard does not account for differences in fuel choices and prices, which strongly influence the economics of energy use. Results presented here should be useful in assessing energy-efficient design alternatives for new mobile homes for different locations, fuel choices and prices, and other pertinent variables.     

困境中的变革——低碳生态城市背景下的建筑能源规划

自从工业革命的爆发,人类的发展一方面导致了城市与自然的隔离,对生态环境的冲击及与自然的对抗。从某种意义上来说城市已成为破坏大自然的"暴力推土机";另一方面,由于人类这种疯狂式的发展,地球资源已经消耗的差不多了,生态环境也濒临崩溃的边缘。既然工业文明是一条不可持续的道路,人类社会必然要转向生态文明,真正的生态发展离不开合理的规划与利用能源。作为世界"耗能大户"的建筑行业,目前在中国等发展国家中还缺乏相应完善的建筑能源规划,本文正是从这点出发,希望为城市的可持续发展提出些许有益的参考。     

Statistical analyses on winter energy consumption characteristics of residential buildings in some cities of China

The purposes of this paper are to analyze winter energy use of residential buildings in different cities of China, and to figure out the influence factors of winter residential energy use. The investigated residences were located in seven typical cities of five architectural thermotechnical design zones. Questionnaire surveys revealed building characteristics, household characteristics, the utilization of domestic appliances, and thermal environment in winter. Winter energy consumption in different cities bears obvious regional characteristics. In south China, Hong Kong has the largest mean household energy use amount, and Changsha and Chongqing follow Hong Kong; Kunming in the warm zone has the small energy use. In north cities, if district space heating is excluded from total energy use, Urumqi and Xi’an have the energy use at the smallest level, but space heating use is very huge. The energy use amounts of space heating of Tangshan, Urumqi and Xi’an are several times as large as the amounts of all the end uses in the southern cities. The analysis on influence factors of winter energy use are made for Chongqing and Hong Kong, respectively, by Quantification Theory I, and the results show there exist obvious differences in influence factors between the two cities.     

City size,prices, and efficiency for individual goods and services

Studies indicate that the cost of living either is the same or rises slightly with the size of cities. This suggests — though it does not imply — that prices of goods and services are as high or higher in larger cities than in smaller cities. But is this really so? And if so, does this imply that costs of distribution (and of the production of services) are higher in bigger cities? The relationship of prices to the sizes of cities is examined for 193 individual goods and services and for 23 broad groups. Price alone does not indicate efficiency. It is well-established that wages for the same work at given skill levels are higher in larger cities. Therefore, the total real inputs may be lower in a larger city, even if price is higher, which indicates better efficiency in larger cities. Study of individual goods and services, and of groupings of them, enables us to go beyond prices to learn which categories are offered more efficiently and which less efficiently in larger cities. We find that for most goods, economic cost decreases rather than increases with city size.     

A new clustering and visualization method to evaluate urban heat energy planning scenarios

Spatial visualization is a very useful tool to help decision-makers in the urban planning process, i) to define future energy transition pathways, ii) to implement energy efficiency strategies and iii) to integrate renewable energy technologies in the context of sustainable cities. There is thus a need to develop new tools to understand the energy consumption patterns across cities. Statistical methods are often used to understand the driving parameters of energy consumption but rarely used to evaluate future urban refurbishment scenarios. Simulating whole cities using energy demand softwares can be very extensive in terms of computer resources and data collection. A new methodology, using city archetypes, is hence proposed to simulate the energy consumption of urban areas and to evaluate urban energy planning scenarios. The objective of this paper is to present a solid framework and innovative solution for the computation and visualization of energy saving at the city scale. The energy demand of cities, as well as the microclimatic conditions, are calculated by using a 3D model designed as function of the real city urban geometrical and physical characteristics. Data are extracted from a GIS database. We demonstrate how the number of buildings to be simulated can be drastically reduced thereby significantly decreasing the computational time and without compromising the accuracy of the results. This model is then used to evaluate the influence of two sets of refurbishment solutions. The energy consumption are then integrated back in the GIS to identify the areas in the city where refurbishment works are needed more rapidly. The city of Settimo Torinese (Italy) is used as a demonstrator for the proposed methodology, which can be applied to medium-sized cities worldwide with limited amount of information.     

Energy Cost Burdens for Low-Income and Minority Households

Abstract

Problem, research strategy, and findings: Of the three primary components of housing affordability measures—rent, transportation, and utilities—utility costs are the least understood yet are the one area where the cost burden can be reduced without household relocation. Existing data sources to estimate energy costs are limited to surveys with small samples and low spatial and temporal resolution, such as the American Housing Survey and the Residential Energy Consumption Survey. In this study, we present a new method for small-area estimates of household energy cost burdens (ECBs) that leverages actual building energy use data for approximately 13,000 multifamily properties across five U.S. cities and links energy costs to savings opportunities by analyzing 3,000 energy audit reports. We examine differentials in cost burdens across household demographic and socioeconomic characteristics and analyze spatial, regional, and building-level variations in energy use and expenditures. Our results show the average low-income household has an ECB of 7%, whereas higher income households have an average burden of 2%. Notably, even within defined income bands, minority households experience higher ECBs than non-Hispanic White households. For lower income households, low-cost energy improvements could reduce energy costs by as much as $1,500 per year.

Takeaway for practice: In this study we attempt to shift the focus of energy efficiency investments to their impact on household cost burdens and overall housing affordability. Our analysis explores new and unique data generated from measurement-driven urban energy policies and shows low-income households disproportionately bear the burden of poor-quality and energy-inefficient housing. Cities can use these new data resources and methods to develop equity-based energy policies that treat energy efficiency and climate mitigation as issues of environmental justice and that apply data-driven, targeted policies to improve quality of life for the most vulnerable urban residents.