Net Zero Energy Solar Buildings Research Articles

Development of the smart photovoltaic system blind and its impact on net-zero energy solar buildings using technical-economic-political analyses

It is expected that the rooftop photovoltaic (PV) systems can realize net-zero energy solar buildings (nZESBs), but it is not enough by itself. To realize 100% of nZESBs, the smart photovoltaic system blind (SPSB) was proposed to generate electricity in the PV system and to reduce indoor cooling demands through the shading effect in the blind system. Before its implementation, this study aims to investigate the impact of the proposed SPSB on nZESBs, which is conducted in three ways (i.e., technical, economic, and political analyses). The detailed results can be summarized as follows: (i) technical analysis: when applying the SPSBCIGS&2-axis (which represents the SPSB with the copper-indium-gallium-selenide (CIGS) PV panel and the two-axis tracking system), its energy self-sufficiency rate was determined to be 1.25–2.31 times superior to other alternatives; (ii) economic analysis: in terms of the NPV25 (net present value at year 25), SPSBCIGS&2-axis was determined to be 1.41–2.97 times superior to others; in terms of the SIR25 (savings-to-investment ratio at year 25), 1.14–1.26 times; and in terms of the break-even point, 1.4–3.0 years; and (iii) political analysis: the grid-connected utilization plan including solar renewable energy certificates (GCincl.SREC plan) was determined to improve the economic profitability of the proposed SPSB.

NOVEL INTEGRATED DESIGN STRATEGIES FOR NET-ZERO-ENERGY SOLAR BUILDINGS (NZESBS) IN NANJING, CHINA

The connotations and denotations of the term net-zero-energy solar buildings (NZESBs) have been in constant flux because of continuous developments in solar heating technology, solar photovoltaic (PV) technology, building energy-storage technology, regional energy-storage technology, and energy-management systems. This paper focuses on innovative strategies for implementing NZESBs in Nanjing, China. These strategies include integrated architectural design, including passive solar design (respecting climatic characteristics and conducting integrated planning based on the environment, building orientation, distance between buildings, building shape, ratio of window area to wall area, and building envelope) and active solar design (integration of the solar-energy-collecting end of the system – collectors and PV panels – with the building surface – roof, wall surfaces, balconies, and sun-shading devices – and the integration of solar-energy transfer and storage equipment with the building). Some Nanjing-specific recommendations and findings on NZESBs are proposed. The results illustrate that NZESBs can be realized in Nanjing if solar energy technologies are appropriately integrated with the characteristics of Nanjing's geography, climate and buildings.

A Revolution for Architecture and Photovoltaic's Zero Energy Buildings: A New Opportunity and Challenge for Technology Based Design

The recast of the European Directive 2010/31/EU establishes that starting from the end of 2020, all new buildings will have to be Nearly Zero Energy Buildings According to this directive, 'Nearly ZEB' means a building that has a very low energy yearly energy consumption, which can be achieved by both the highest energy efficiency and by energy from renewable sources, A relevant international effort on the subject of the Net Net ZEBs-Net ZEB meaning that the buildings are connected to an energy infrastructure-is ongoing in the International Energy Agency (IEA), joint Solar Heating and Cooling (SHC) Task 40 and Energy Conservation in Buildings and Community Systems. Net Zero Energy Solar Buildings' both from the theoretical and practical points of view, this new 'energy paradigm'-or the Net ZEB) balance- might be a revolution for architecture and for Photovoltaic's (PV), too.The engineering only research taking into account mainly the energy aspects seems to be not sufficient to ensure the diffusion of ZEB models: in achieving the ZEB target, a major role will be played by architects and designers, who are amongst the main actors of this revolutionary change. More precisely, because the form of our buildings and cities might change radically because of this new energy requirement, the way architects will take up the challenge of designing ZEBs is crucial, as architects are highly responsible of the form of the city and of its symbolic meanings.In a near future, buildings will be designed to need very little energy (passive design strategies for energy efficiency) and to integrate active surfaces (i.e. PV modules) for generating energy. In the future, design has to consider not only the space we use directly but also the space required to provide for electrical and thermal energies from renewable sources: the surface necessary for placing the energy generation devices. This area can be defined as the 'building's energy footprint' . Because the renewable energy generation systems, in contrast to conventional Energy sources, are visible, for the first time in the tradition of architecture, energy can take a 'form' (i.e. shape, colors and features of a PV generator), and architects are responsible for designing this form(s). Photovoltaic's has many potentialities in a ZEB scenario, thanks to its features and enormous decrease in cost. Because of the high energy consumption of the European countries, PV can contribute significantly to the reduction of the primary, conventional energy supply, as well as to the reduction of the CO2 emissions PV seems to be technically the easiest way to obtain the zero energy balance, as the recent, sharp, drop in prices makes it competitive even with active solar thermal collectors and building materials in general.Photovoltaics is able to generate electric energy from the direct conversion of the sunlight; it can power any kind of energy request of the building (thermal and electrical), with the consequence that a ZEB could be theoretically entirely powered by Photovoltaic.

Photovoltaics' architectural and landscape design options for Net Zero Energy Buildings, towards Net Zero Energy Communities: spatial features and outdoor thermal comfort related considerations

AbstractNet Zero Energy Building (NetZEB) design has become a crucial topic of research in recent years. Because of its complexity, discussion has been carried out on methodological criteria useful to define and assess NetZEBs (building system boundary, conversion factors, energy balance, interaction with the grid, monitoring, etc.), mainly with the engineering approach, and a number of case studies worldwide have been investigated. In regard to photovoltaics' (PV) design, research demonstrated the following: (1) PV is an indispensable technology for meeting the net zero energy target; (2) meeting the target of the net zero energy balance at the architectural scale (by using only the surfaces of the building envelope to place renewables) is very difficult and therefore (3) an extension of the balance boundary to a wider scale is needed. That is the concept of NetZEB should be advanced towards the one of Net Zero Energy Communities (NetZECs). In view of such an enlargement of the design domain, this paper investigates architectural and landscape design options (spatial features and outdoor thermal comfort considerations) for PV, on the basis of the analysis of case studies collected and assessed in the framework of the International Energy Agency Solar Heating and Cooling Programme ‐ Energy in Buildings and Communities Programme (SHC‐EBC) Task 40‐Annex 52 Net Zero Energy Solar Buildings. Considering that the traditional understanding of the use of PV in buildings, mainly rooted in technological and morphological considerations, is not sufficient to describe all the issues emerging from this analysis, this paper is a contribution for setting a new cognitive framework in view of PV design for NetZECs. Copyright © 2014 John Wiley & Sons, Ltd.

The impact of urban design decisions on net zero energy solar buildings in Sweden

Planning for future energy-efficient and energy-producing buildings requires specific knowledge during the design process. Many design decisions taken by urban planners –form, density, roof type and orientation – have a significant effect on the conditions of such buildings, although urban planners might not always be aware of the effect of their design. This study examines the effects of important design decisions on the solar energy potential of net zero energy solar buildings. Typical Swedish building blocks with varying form, density, roof type and orientation were used to simulate the annual solar irradiation and energy production, and to calculate the load match for heating and electricity under Swedish conditions. Results of this study show that the urban density is the most influential parameter on the solar potential of building blocks. Furthermore, flat roofs often returned the highest load match value, while the effect of orientation on the solar potential turned out not to be that straightforward. With the results of this study, urban planners can make better informed decisions, while it also provides a ground for the net zero energy solar buildings discussion by exposing the boundaries of such buildings in the urban environment.

How Net Zero Energy Buildings and Cities Might Look Like? New Challenges for Passive Design and Renewables Design

This paper deals with new considerations about the design of Net Zero Energy Buildings and Net Zero Energy Neighbourhoods in the future. The perspectives presented here are the results from an international work named Task40/Annex52 “Towards Net Zero Energy Solar Buildings” conducted within the framework of the International Energy Agency (SHC-EBC) and in particular from the sub-group working on Solution Sets and case studies. We will see through case studies in different climates that the design scale to reach the Zero Energy goal is not the building anymore. The design of renewables as well as passive strategies must be extended to the whole neighbourhood.

From Solar Building Design to Net Zero Energy Buildings: Performance Insights of an Office Building

Net Zero-Energy Buildings Performance has gained more attention since the publication in 2010 of the EPBD recast [1]. Successful implementation of such an ambitious target depends on a great variety of factors. With a literature full of theoretical advice and a building industry rife with myths about the value of technologies, the present study intend to unveil an sustainable framework for sharing insights into NetZEB methodology applied in an Portuguese office building, Solar XXI, based on the authors experience in the ongoing research carried out within International Energy Agency SHC Task 40 - ECBCS Annex 52, “Towards Net Zero Energy Solar Buildings”

Design Issues for Net Zero-Energy Buildings

Net Zero-Energy Buildings (NZEBs) have received increased attention in recent years as a result of constant concerns about energy supply constraints, decreasing energy resources, increasing energy costs and the rising impact of greenhouse gases on world climate. Promoting whole building strategies that employ passive measures together with energy efficient systems and technologies using renewable energy became a European political strategy following the publication of the Energy Performance of Buildings Directive recast in May 2010 by the European Parliament and Council. However designing successful NZEBs represents a challenge because the definitions are somewhat generic while assessment methods and monitoring approaches remain under development and the literature is relatively scarce about the best sets of solutions for different typologies and climates likely to deliver an actual and reliable performance in terms of energy balance (consumed vs generated) on a cost-effective basis. Additionally the lessons learned from existing NZEB examples are relatively scarce. The authors of this paper, who are participants in the IEA SHC Task 40-ECBCS Annex 52, “Towards Net Zero Energy Solar Buildings”, are willing to share insights from on-going research work on some best practice leading NZEB residential buildings. Although there is no standard approach for designing a Net Zero-Energy Building (there are many different possible combinations of passive and efficient active measures, utility equipment and on-site energy generation technologies able to achieve the net-zero energy performance), a close examination of the chosen strategies and the relative performance indicators of the selected case studies reveal that it is possible to achieve zero-energy performance using well known strategies adjusted so as to balance climate driven-demand for space heating/cooling, lighting, ventilation and other energy uses with climate-driven supply from renewable energy resources.

Goal: Zero Energy Building Exemplary Experience Based on the Solar Estate Solarsiedlung Freiburg am Schlierberg, Germany

Zero energy consumption. The goal sounds simple and is presented excessively in variations all over the world. Energy and environmental politics demand zero consumption as a long-term goal, marketing has discovered the concept and first buildings and settlements aiming at balanced energy or emission budgets have been constructed. As an example, the German Federal Government specifies in its fifth energy research programme (2005): For new buildings, the goal is to reduce the primary energy demand, i.e. the energy demand for heating, domestic hot water, ventilation, air-conditioning, lighting and auxiliary energy, again by half compared to the current state of the art. The long-term goal is zero-emission buildings. England and the USA aim for zero carbon developments and net-zero energy buildings (DOE, 2009) in political programmes. The Vatican accepted the offer of climatic “indulgence”—and thus became the first country in the world to completely compensate its carbon emission (Spiegel online, 2007). Megaprojects in the growth regions of the Arabian Gulf and China advertise with a CO2-neutral balance. A Zero Carbon Community is to be created in Masdar, Abu Dhabi (Foster, 2007), and the first Chinese carbon-neutral ecocity was planned for Dongtan, Shanghai (Pearce, 2009). Not only to aid international communication, but also to further the processes required to solve energy-related problems, it is essential that key words, central concepts, their usage and their relationships be clarified. This article intends to contribute to this clarification based on the monitored example of a solar estate. Net zero energy building, equilibrium building, carbon neutral city—the accounting method varies, depending on motivation and point of view. If the focus is on finite and scarce resources, energy is the currency; CO2-equivalent emissions are considered if global warming and public health is the issue; the cost of energy is what concerns a tenant paying for heating and electricity. A balance in one set of units can be converted to another, but the conversion factors often also shift the balance point. Energy will be used as the reference quantity in the following article, which prevents confusion with non-energy measures (e.g. carbon credits for forestry) and avoids the nuclear power debate, in which nuclear power is partly calculated as being CO2 neutral. The diversity of concepts is an indicator that a scientifically based methodology is still lacking, though initial publications focus hereon (Pless et al. 2009). Since October 2008, a group of experts in the International Energy Agency has been addressing this issue under the heading, Towards Net Zero Energy Solar Buildings (Riley et al. 2008). The goal is to document and analyse outstanding examples that are close to being net zero-energy buildings, and while doing so, to develop the methodology and tools for working with such buildings. The Chair of Technical Building Services, University of Wuppertal, is co-ordinating the methodological work. The zero-energy approach—still under construction—will here be presented using a solar estate as an illustration.

A Review Of Design Processes For Low Energy Solar Homes

In recent years, there have been a growing number of projects and initiatives to promote the development and market introduction of low and net-zero energy solar homes and communities. These projects integrate active solar technologies to highly efficient houses to achieve very low levels of net-energy consumption. Although a reduction in the energy use of residential buildings can be achieved by relatively simple individual measures, to achieve very high levels of energy savings on a cost effective basis requires the coherent application of several measures, which together optimise the performance of the complete building system. This article examines the design process used to achieve high levels of energy performance in residential buildings. It examines the current design processes for houses used in a number of international initiatives. The research explores how building designs are optimised within the current design processes and discusses how the application of computerised optimisation techniques would provide architects, home-builders, and engineers with a powerful design tool for low and net-zero energy solar buildings.