1,720,993 research outputs found
LAND INTEGRATED PHOTOVOLTAICS. The New Energy Landscape of Europe
Full text linkThe European Union member states are committed to installing a total of 84,000 MW worth of photovoltaic systems by 2020, in order to help meet the target of 20% energy share from renewable sources, as mandated by Directive 2009/26/EC. Most importantly, a major portion of the new capacity will have to be installed as very large, open-field power plants. Much of the efforts to date by the photovoltaic industry and energy policy makers have been directed at creating efficient and economically viable models for the implementation of PV technology in the built environment. Today, however, growing public opposition to large-scale installations is becoming a significant obstacle to greatly expanding the photovoltaic installed capacity and to fulfilling the promises of independency from fossil fuels. If EU member states are to reach the target mandated by the European Commission, then social, aesthetic and cultural concerns – not just technical ones – must be addressed as well. Accordingly, the present concept for a demonstration of Land Integrated Photovoltaics aims at providing a culturally acceptable model for large-scale photovoltaic installations across the European landscape, in the context of the new energy policies of the European Union.
The establishment of the City – from its very inception – is the result of a fundamental separation between places of consumption – located within the city limits – and places of production, where enough surpluses of raw materials and food are created to support city development. The impact of cities on places elsewhere, be it hinterlands or places far away – the so-called city footprint – is of extraordinary proportions. Yet the public at large, including policy makers and urban planners, seems utterly oblivious to the basic requirements of a functioning city: waste management and sewage treatment, air and water filtration, energy and heat generation, food production and processing are by and large still considered engineering annoyances to be hidden away or disregard altogether. As a result, the dislocation of production activities has only increased since the industrial revolution: over the past 150 years, the massive loss of natural land to the combined effect of relentless expansion of urban areas, modern infrastructures and extraction of minerals, resulted in a drastic reduction of biodiversity, in air and water pollution, and the depletion of natural resources. We believe that the key to reverting the current trend is the re-integration of places of production - including energy infrastructures - within the built environment.
Historically, energy production has been based on a centralized model, where large power plants produce hundreds of megawatts in a single location. New energy technologies - such as photovoltaic, solar thermal, geothermal and wind micro-turbines - bring the promise of a decentralized model, with power produced at or near the point of consumption, with many advantages over the standard centralized model, in terms of both energy gains and reduced line losses. Interestingly, there is also a much lower pollution, noise, and visual impact associated to these technologies, allowing for the production plant to be near or in the city. Sunlight is a ubiquitous natural resource that can be found everywhere, yet current models of large-scale, open-field photovoltaic installations follow the paradigm of extractive industries - which depends on localized resources that only occur in small sporadic areas. The current study explores alternative logics of distribution that are not based exclusively on space efficiency or economy of scale; instead, it conceives of photovoltaic panels as a modular component distributed over large areas of land, enabling self-sufficient residential and productive districts.
The project aims at identifying opportunities to supply the anthropized environment with solar energy technology systems, in ways that are more efficient, less costly and more sustainable than current energy production systems. Most importantly, the research attempts an investigation of both the cultural and the technological overlay of human activities, in order to identify strategies of occupations that are compatible with preexisting uses and that respect the natural vocation of the land
Solar Sculpting: Housing Morphology and Collective Energy
No full textFor more than ten years, New York City has promoted energy efficiency policies—including PlaNYC and the Greener, Greater Buildings Plan—that will radically reshape the education of architects toward energy performance in buildings, reduction of emissions, and the efficient use of resources. This series of undergraduate research studios conducted at the Pratt Institute School of Architecture, investigates the relationship between the building form and energy performance, using form-finding algorithms based on solar radiation to shape mid-rise housing typologies for New York City. Funded by the Institute of Design and Construction Foundation from 2019 until 2021, these studios explore the important environmental design opportunities that exist within building morphology, particularly in residential buildings that are responsible for most of the greenhouse gas (GHG) emissions and power consumption. By integrating and extending current solar technologies such as photovoltaic (PV) and solar thermal (ST) for the predominantly vertical infrastructure of the city, this research targets innovative building mass and surface strategies that are highly energy efficient, generate onsite renewable energy, and produce a new aesthetic for sustainable construction. Additionally, solar driven design fosters distributed energy solutions and collective resources generating new ways of living and working in cities. As part of the initiative, we have also formed an international exchange program between our two institutions, the Pratt Institute and the Politecnico di Milano, to share content and expertise
Use of 3D tessellation in curtain wall facades to improve visual comfort and energy production in buildings
Full text linkIn the vast majority of new buildings, energy and comfort requirements are met mostly by active systems that are often expensive, energy intensive, and complex to maintain. At the same time, advances in the use of digital tools for the design and fabrication of unitised curtain wall systems have substantially reduced the costs associated to non-planar surfaces in building envelopes. As a result, buildings deploy an increasing level of surface geometry articulation that is mostly used for decorative effects. By and large, the flourishing of a new formal vocabulary, enabled by digital tools, rarely translated into buildings that perform better. The research proposes the use of non-planar surface geometries for precise calibration in tilt angle and orientation of individual panels in curtain walls, as an effective passive design strategy. The goal is to improve visual comfort for users, limiting potential glare without the use of shading or blinds and, at the same time, to provide high potential for PV production without negatively affecting daylighting levels in the building interiors. The study explores four families of three-dimensional geometries, based on size limitations and other design constraints typically associated to unitized curtain wall systems. The investigation takes into account aspects such as local climate data, orientation, glass properties, morphology of the façade unit, indoor visual comfort, energy efficiency and energy production. Results show that all four families can be optimised to meet LEED requirements of sDA > 50% and ASE < 10% in office buildings, delivering better performances when compared to a flat facade
Solar Typologies: A Comparative Analysis of Urban Form and Solar Potential
Full text linkEfficient use of energy in the construction sector is a pillar of the European Union’s 2050 climate protection goals, yet legislation makes no explicit reference to urban morphology or building form, which are recognized as key to energy performance in buildings. Rapidly changing energy standards and new requirements for on-site energy production demand a vigorous scrutiny of established urban typologies that are largely the product of an older energy regime. The research explores a set of 312 building shapes with floor-to-area ratio (FAR) of 3 within a given plot to identify emerging trends, ranges, and correlations between geometric variables, visual comfort, and energy indicators. Cases are grouped and evaluated in relation to three main urban typologies to highlight unique features related to each typology. The paper also compares two groups of results related to passive and active solar potential, respectively, to identify formal traits that are specific to each of these two design strategies. Finally, the research ranks design options based on total energy use taking into account the energy need for artificial lighting as well as contributions from both passive energy savings and active energy production. Results show that energy demand across cases varies by a factor 2 for passive strategies and a factor 5 when active potential is considered based on shape alone. Best results are clearly positioned at the two extremes of the geometric and proportional range. On the one hand, low-rise compact bar and courtyard buildings that are perhaps most prevalent in our cities today may be effectively retrofitted to meet active energy targets. On the other hand, extremely tall and slim towers appear to be the only typology in the study with the potential to achieve zero-energy status by virtue of their form alone. The work sheds light on the formal implications of EU energy mandates and offers a glimpse of how buildings may adapt to the combined selective pressures of high on-site energy fraction and low energy use to shape our future cities
Solar Species: Energy Optimization of Urban Form Through an Evolutionary Design Process
Full text linkThis paper proposes design guidelines to enhance energy efficiency and energy generation potential in active solar buildings. Additionally, it presents a variety of optimized urban forms characterized by attributes such as shape, layout, and number of buildings on the plot. These urban configurations are classified into solar species, each associated with a distinct range of high passive and active solar potential. These results were achieved by developing and applying a simulation-driven, multi-objective optimization technique for the early-stage design of a residential building cluster in a temperate climate. This method leverages both passive and active energy indicators, employing a genetic algorithm to identify optimal forms that maximize active solar potential while also minimizing operational energy demand. The approach utilizes a parametric modelling routine that relies on vertical cores and horizontal connections to produce design iterations featuring irregular geometry, while ensuring structural continuity and means of egress. The findings reveal a significant variability in onsite energy generation, with optimized solutions differing by a factor of 2.5 solely based on shape, underscoring the critical role of active solar potential. Taken together, these results hint at the descriptive and predictive capabilities of these solar species, making them a promising heuristic model for characterizing urban form in relation to energy performance
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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