The financials of constructing a solar PV for net-zero energy operations on college campuses

The LACCD has a goal of establishing net-zero energy operations across its nine campuses. The project faces many challenges, including limited open areas for installing solar PV, increasing energy consumption challenges associated with campus energy growth and the high cost of installing solar PV. A previous study by Kwan and Hoffmann (2010) found that the LACCD would need to install a 9.5 MW solar PV array in order to meet total campus energy demand on a college campus through the year 2020. This paper attempts to evaluate the financial feasibility of such a project, taking into account the current local, state and federal renewable energy incentives available. We find that despite the availability of financial incentives by local municipal utility companies including installation rebates and net metering, the cost of electricity generated by solar PV still remains approximately 30% higher than electricity generated by fossil fuels. We also find that the optimal solar PV array size from a financial standpoint is one that is sized to generate and meet all electrical demand during sunlight hours. Any array larger than this yields diminishing returns. Finally our analysis examined the influence of per kW installation cost and found that only when prices dropped to $3.00 per installed watt did a net-zero energy solar PV array have an NPV of 0.     

The impact of the COVID-19 pandemic and behavioral restrictions on electricity consumption and the daily demand curve in Turkey

The rapid spread of COVID-19 has severely impacted many sectors, including the electricity sector. The reliability of the electricity sector is critical to the economy, health, and welfare of society; therefore, supply and demand need to be balanced in real-time, and the impact of unexpected factors should be analyzed. During the pandemic, behavioral restrictions such as lockdowns, closure of factories, schools, and shopping malls, and changing habits, such as shifted work and leisure hours at home, significantly affected the demand structure. In this research, the restrictions and their corresponding timing are classified and mapped with the Turkish electricity demand data to analyze the estimated impact of the restrictions on total demand and daily demand profile. A modulated Fourier Series Expansion evaluates deviations from normal conditions in the aggregate demand and the daily consumption profile. The aggregate demand shows a significant decrease in the early phase of the pandemic, during the period March–June 2020. The shape of the daily demand curve is analyzed to estimate how much demand shifted from daytime to night-time. A population-based restriction index is proposed to analyze the relationship between the strength and coverage of the restrictions and the total demand. The persistency of the changes in the daily demand curve in the post-contingency period is analyzed. These findings imply that new scheduling approaches for daily and weekly loads are required to avoid supply-demand mismatches in the future. The long-term policy implications for the energy transition and lessons learned from the COVID-19 pandemic experience are also presented.     

The impact of coordination on wholesale market participation: The case of the U.S. electricity industry

Coordination costs in a wholesale electricity market are a relevant public policy consideration. The mitigation of coordination costs, all else equal, should increase participation in the marketplace. Since Federal Energy Regulatory Commission (FERC) Order 888 was issued in 1996, the level of trading activity in bulk electricity markets has increased significantly. In 1999, FERC issued Order 2000 to advance the role of regional transmission organizations (RTOs) in the restructured marketplace for wholesale electricity. RTOs have the potential to reduce the coordination costs, while also having the countervailing effect of causing market participants to incur compliance costs. This paper utilizes the diversity of the United States electricity market and a panel data set representing electric utilities for the period 1990–2009 to study the effects that RTOs have had on wholesale electricity exchange. The paper finds that the presence of a transparent wholesale marketplace for electricity has the effect of increasing participation, but this participation is uneven across types of electric utilities. Greater participation is seen for investor-owned and larger utilities. The results have important implications for policy aimed at wholesale markets and the transmission organizations, as the opportunities afforded by transparency may not be uniformly distributed across all market participants.     

曲线张拉技术对预应力混凝土双T板结构性能影响研究

曲线张拉技术能够有效的改善预应力混凝土双T板在制作和运输过程中出现的表面裂缝问题,但是该技术对于预应力双T板结构性能的影响有待于进一步研究。本文通过采用普通张拉技术和采用曲线张拉技术的JSTB24-2型预应力混凝土双T板结构性能检测对比试验,研究了曲线张拉技术对预应力混凝土双T板承载力、挠度以及抗裂等方面的影响,并进行了机理分析,研究结论可对预应力混凝土双T板的生产提供指导性建议。     

Dreams,Propaganda and Harsh Realities: Landscapes of group settlement in the forest districts of Western Australia in the 1920s

After the First World War, opportunities for settlement in Britain's imperial territories were pursued vigorously. It is explored how early 1920s ideas about the role of colonization as a means to create ideal 'British' settlements overseas rekindled the thinking of the post-Napoleonic period. In particular, these ideas are examined in the context of the promotion in South West England of 'group settlement' schemes in Western Australia. Sophisticated promotional material, developed to persuade would-be emigrants to settle in rural areas of the dominions, is discussed, and the mismatch between the migrants' expectations and their actual experiences is examined. Although advertising was rarely deliberately inaccurate, the style and imagery employed in posters, newspaper articles, and other media presented notional landscapes that were far less arduous than proved to be the case. The disillusionment of Devon and Cornwall group settlers, once in Australia, and their complaints of having been 'misled', show the distinction between the landscapes of real empire settlement and the more fanciful landscapes of the imagination.     

Dreams, Propaganda and Harsh Realities: landscapes of group settlement in the forest districts of Western Australia in the 1920s

After the First World War, opportunities for settlement in Britain's imperial territories were pursued vigorously. It is explored how early 1920s ideas about the role of colonization as a means to create ideal 'British' settlements overseas rekindled the thinking of the post-Napoleonic period. In particular, these ideas are examined in the context of the promotion in South West England of 'group settlement' schemes in Western Australia. Sophisticated promotional material, developed to persuade would-be emigrants to settle in rural areas of the dominions, is discussed, and the mismatch between the migrants' expectations and their actual experiences is examined. Although advertising was rarely deliberately inaccurate, the style and imagery employed in posters, newspaper articles, and other media presented notional landscapes that were far less arduous than proved to be the case. The disillusionment of Devon and Cornwall group settlers, once in Australia, and their complaints of having been 'misled', show the distinction between the landscapes of real empire settlement and the more fanciful landscapes of the imagination.     

Turning a Deaf Ear: Acoustic Value in the Assessment of Heritage Landscapes

Aesthetic value is one of the fundamental criteria used to determine the cultural heritage significance of important places. In Australia, however, cultural heritage has had only a limited engagement with theories on aesthetics, and as a result, no practical methodology has been developed to identify, describe and assess the acoustic dimension of aesthetic value. This paper critiques the literature on aesthetics that cultural heritage has focused on to date, highlighting its emphasis on the visual qualities of place over other multi-sensory understandings. Recent research into acoustics, particularly based on the concept of the soundscape, is explored in order to develop a qualitative methodology to assist heritage practitioners and others in understanding, describing and evaluating the acoustics of place. The applicability of this approach is demonstrated through the analysis of two cultural landscapes in the south-west of Western Australia.     

The impact of building-integrated photovoltaics on the energy demand of multi-family dwellings in Brazil

Brazil faces a continuous increase of energy demand and a decrease of available resources to expand the generation system. Residential buildings are responsible for 23% of the national electricity demand. Thus, it is necessary to search for new energy sources to both diversify and complement the energy mix. Building-integrated photovoltaic (BIPV) is building momentum worldwide and can be an interesting alternative for Brazil due its solar radiation characteristics. This work analyses the potential of seven BIPV technologies implemented in a residential prototype simulated in three different cities in Brazil (Natal, Brasília and Florianópolis). Simulations were performed using the software tool EnergyPlus to integrate PV power supply with building energy demand (domestic equipment and HVAC systems). The building model is a typical low-cost residential building for middle-class families, as massively constructed all over the country. Architectural input and heat gain schedules are defined from statistical data (Instituto Brasileiro de Geografia e Estatística—Brazilian Institute for Geography and Statistics (IBGE) and Sistema de Informações de Posses de Eletrodomésticos e Hábitos de Consumo—Consumer Habits and Appliance Ownership Information System (SIMPHA)). BIPV is considered in all opaque surfaces of the envelope. Results present an interesting potential for decentralized PV power supply even for vertical surfaces at low-latitude sites. In each façade, BIPV power supply can be directly linked to local climatic conditions. In general, for 30% of the year photovoltaic systems generate more energy than building demand, i.e., during this period it could be supplying the energy excess to the public electricity grid. Contrary to the common belief that vertical integration of PV is only suitable for high latitude countries, we show that there is a considerable amount of energy to be harvested from vertical façades at the sites investigated.     

The impact of renewable energy on household electricity prices in liberalized electricity markets: A cross-national panel data analysis

The main research questions addressed in this paper are: first, have electricity market reforms achieved lower household electricity prices and, second, has the introduction of renewable energy increased household electricity prices in deregulated markets Answers to the questions were derived using static and dynamic panel data analysis from 1991 to 2014 employing explanatory variables such as the extent of electricity market reform and the share of generation from renewable energy resources. The dynamic model suggests that a lower household electricity price is associated with the degree of electricity market reform, while the share of renewable energy in electricity generation is not statistically significant.     

Electricity prices in a competitive market: a preliminary analysis of the deregulated Thai electricity industry

The electricity industry throughout the world is currently undergoing a significant transition towards restructuring and deregulation. Following this new legislation, Thailand has initiated an institutional and structural reform with a belief that this could be the best way forward for the Thai electricity supply industry (ESI) to improve efficiency, lower electricity prices, and tackle financial debts. This paper presents an analysis of the extent to which prices for generation services in a competitive market may differ from regulated electricity prices, if competitive prices are based on marginal costs and regulated prices are based on average costs, by using Thailand as a case study.     

Forward risk premia in long-term transmission rights: The case of electricity price area differentials (EPAD) in the Nordic electricity market

Hedging behaviour among players in derivatives markets have long been explained by forward risk premia. We provide new empirical evidence from the Nordic electricity market and explore the forward risk premia dynamics on power derivative contracts called electricity price area differentials (EPAD). This contract is critical for the market, but its efficiency has been questioned. The study investigates the significance, direction, and magnitude of forward risk premia in individual bidding areas and contract maturities during the period 2001–2013. We test the hypothesis of a negative relationship between forward risk premia and time-to-maturity, for which we find only partial support.     

十九世纪珠江流域文化景观特征 ——基于西方文献的分析

自古以来，河流及其流域构成了一些最 具活力和最复杂的景观。河流维系着人类社会， 人类社会则以多种方式利用河流，从而产生璀璨 的流域文明。广州作为西方人眼中的一座 “神 奇”城市，两千年来一直是中国最重要的海上门 户，现如今，我们可以从外国商人、船长、旅行 者、传教士等游记、报告或图像记录中获得大量 关于珠江流域文化景观的详细描述。本文尝试 将珠江流域的河流系统及其相关的文化景观作 为人类经验的重要组成部分进行研究，透过西 方人的视野，去分析其对珠江流域及其文化景 观的所见所闻，并深入挖掘珠江流域文化景观 的构成与特征，从而归纳出珠江流域文化景观 中的人水共生关系，为珠江流域文化遗产保护 研究提供了全新的视角与思路。     

对中国建筑发展的几点思考——读《20世纪西方建筑史》有感

在全球化背景下的快速城市化发展过程中,中国城市建设在取得不菲成绩的同时也带来了钢筋混凝土林立,空间混乱无序,社区缺乏生气和地域性同质化的城市弊病。基于以上问题,本文梳理了《20世纪西方建筑史》中易被忽略和遗忘的重要规律,反思并提出了有助中国城市建筑发展的思路。     

从皇家禁地到庆典舞台:北京西郊万寿寺的微观格局变迁

本文是对万寿寺建筑群这一微小空间领域由明末至清末三百余年变迁的研究.明代万历生母李太后崇佛及其个人情感归属,替僧制度,西郊的人文地理是万寿寺初创的背景.尔后三百余年,万寿寺历经多次营建变革,畅春园的始建,崇庆皇太后六旬和七旬庆典,慈禧太后六旬庆典无不例外地影响到了组群的建设.文章将史料与实际建制进行联系,分析万寿寺各时...     

中西融汇的生态人文书院——浅析澳门大学横琴新校区书院设计

澳门大学横琴新校区书院设计充分借鉴港澳地区的教育特色和办学模式,以及岭南建筑与南欧建筑的风格特点,开创性地将西方高等教育的住宿式书院制度与传统的中国文化、教育理念融为一体。从宏观的规划,到中观的建筑形态和空间,再到微观的细部风格,在全方位建筑实践的基础上,提出并完善了当代大学书院设计的新理念。实现文化内涵在场所精神指引下与建筑空间环境的有机结合,体现了超越功能需求本身的建筑文化特性的升华。     

Quantification of stormwater runoff using a combined GIS and curve number approach: a case study for an urban watershed in the Ozark Highlands,USA

Managing stormwater runoff is crucial to preserving water quality in rapidly developing urban watersheds. The objective of this study was to develop a methodology to test existing stormwater drainage infrastructure, identify potential areas of improvement, and estimate potentially contaminated runoff by combining two widely used stormwater runoff prediction models. A watershed containing much of the University of Arkansas-Fayetteville campus was targeted for this study because stormwater from this watershed drains into a local river designated as an impaired water body due to siltation. The curve number method was used to estimate runoff for various flood-return periods and antecedent moisture conditions, while a flow-direction model integrated topography, land use, and stormwater drainage infrastructure in a GIS. The methodology developed and results generated will help stormwater planners visualise localised runoff and potentially adapt existing drainage networks to accommodate runoff, prevent flooding and erosion, and improve the stormwater quality entering nearby surfacewater bodies.     

Examining homelessness in Germany: The impact of regional housing market conditions on homelessness in North Rhine‐Westphalia,Germany

This paper proposes a simple model of the housing market and homelessness by taking into consideration both flat size and quality. A critical income ensuring positive housing consumption can be determined. The empirical analysis of districts in North Rhine‐Westphalia suggests that conditions on the housing market, income levels and several variables depicting a district's social environment are important drivers of homelessness: high rents and relatively few vacant small flats lead to an increase in homelessness. The condition of vacant flats significantly affects homelessness levels too. Homelessness also increases when the share of those with a very low income is higher, since this makes it more difficult to reach the critical income.     

Salt tracer experiments in constructed wetland ponds with emergent vegetation: laboratory study on the formation of density layers and its influence on breakthrough curve analysis

Constructed wetlands are a rapidly expanding and intensively studied wastewater treatment system. One of the main types in use is the free water surface (FWS) wetland or wetland pond. In studies on these ponds, salt tracer experiments are a convenient tool to determine travel time distributions, which are, in turn, related to hydraulic and sedimentation (trapping) as well as nutrient removal efficiencies. Typically, flows encountered in constructed wetland ponds are characterized by low Reynolds numbers, at times even within the laminar flow regime. In such conditions the injection of salt may cause strong density effects, thereby threatening the usefulness of the recorded breakthrough curves. The processes and mechanisms governing the formation of density stratification due to salt tracer injections into wetland ponds with emergent vegetation were studied in the laboratory. The results reported are expected to be useful in the planning of future field tracer experiments.     

The regulation and impact of eight Australian coal mine waste water discharges on downstream river water quality: a regional comparison of active versus closed mines

Water quality of rivers that received coal mine wastes from four active and three closed mines were investigated, focusing on ecologically hazardous pollutants. Zinc and nickel concentrations were highest downstream of two closed mines, particularly from the Canyon mine that closed 20 years earlier. Coal mine wastes increased nickel concentrations in waterways by an average of 25 times. The average concentration of zinc increased below mines waste discharges from 8.6 µg/L (upstream) to 83.4 µg/L (downstream). All coal mine discharges increased river salinity. Salinity increased by more than 6 times (upstream mean 101.4–741.7 µS/cm downstream). This study provides a reminder that water pollution from coal mines is a major environmental issue for both active and closed mines. The study highlights the need for more stringent and consistent environmental regulation for all mines, including key hazardous pollutants from wastes emerging from both active and closed mines.     

The impact of a reservoir on the physicochemical properties of water in a mountain river

The article presents the changes in the physicochemical properties (temperature, conductivity and pH) of the water in the Ropa River in the Polish Carpathians that were caused by the Klimkówka Reservoir, which was commissioned for operation in 1994. The study uses data mainly from daily measurements of the physicochemical properties of the water in the Ropa River. The measurements were taken during the period prior to the reservoir being built (1982–1993) and from the period after the dam became operational (1994–2006). The measurements were conducted 16 km downriver from the dam. The conducted analysis shows that the Klimkówka Reservoir radically changed the thermal conditions and the annual cycle for water conductivity in the Ropa River. The pH of the water in the Ropa River experienced the smallest changes.