A Critical Analysis of Research Gaps in Nearly Zero Energy Buildings

This Article introduces the advantage of using Building Information Modeling (BIM) technology to achieve the Zero Energy (ZE). A zero-energy building (ZE), also is known as a Zero Net Energy (ZNE) building, or Net-Zero Energy Building (NZEB). Net zero building is a building which is zero net energy consumption, which means that the total amount of energy used by the building on an annual basis is equal to the amount of renewable energy created on the site. A net Zero-Energy Building (ZEB) is a residential or commercial building with greatly reduced energy needs through efficiency gains such that the balance of energy needs can be supplied with renewable technologies. In the concept of the net ZEB is a building which could reduce energy needs through efficiency and gain that balance of the energy needs via different renewable technologies. This paper will touch the necessity of integrating solar panels and wind energy design with BIM (Building Information Modeling) and how could that lead to achieve and reach the ZNEB (Zero Net Energy Building). The article will discuss the gap between modeling tools in energy and the achievement of sustainable features in models that produce for best design results and construction material in the project by using BIM (Building Information Modeling) to reach the ZNEB (Zero Net Energy Building).
 Keywords: Zero Net Energy (ZNE); Zero Energy Building; Zero Energy; Net-Zero Energy Building (NZEB); Zero-Energy Building (ZEB); Building Information Modelling (BIM)

Net-zero exergoeconomic and exergoenvironmental building as new concepts for developing sustainable built environments

Impact of renewable energy technologies on the embodied and operational GHG emissions of a nearly zero energy building

Zero-energy buildings have attracted great attention in China. Limited research about typical high-rise, zero-energy residential buildings in China was found. To figure out the potential of zero-energy buildings in northern China, a techno-economic analysis of a typical residential building adapted to the nearly zero energy building (NZEB) standards in the cold region of China was carried out in detail in this paper. Firstly, the feasibility of different building energy efficiency technologies was figured out in the passive design level. Secondly, the annual energy balance of the nearly zero-energy building model was investigated. Finally, detailed economic and environmental analyses were performed. The results show that the energy consumption of space heating and cooling of a typical high-rise, nearly zero-energy building could decrease to 11.1 kWh/(m2·a) in Beijing. The conclusions could provide a reference and design basis for the development of zero-energy residential buildings in northern China in the near future.

Design considerations for net zero energy buildings for intensive, confined poultry production: A review of current insights, knowledge gaps, and future directions

This study evaluates potential aggregate effects of net-zero energy building (NZEB) implementations on the electrical grid in simulation-based analysis. Many studies have been conducted on how effective NZEB designs can be achieved, however the potential impact of NZEBs have not been explored sufficiently. As significant penetration of NZEBs occurs, the aggregated electricity demand profile of the buildings on the electrical grid would experience dramatic changes. To estimate the impact of NZEBs on the electrical grid, a simulation-based study of an office building with a grid-tied PV power generation system is conducted. This study assumes that net-metering is available for NZEBs such that the excess on-site PV generation can be fed to the electrical grid. The impact of electrical energy storage (EES) within NZEBs on the electrical grid is also considered in this study. Finally, construction weighting factors of the office building type in U.S. climate zones are used to estimate the number of national office buildings. In order to consider the adoption of NZEBs in the future, this study examines scenarios with 20%, 50%, and 100% of the U.S. office building stock are composed of NZEBs. Results show that annual electricity consumption of simulated office buildings in U.S. climate locations includes the range of around 85 kWh/m2-year to 118 kWh/m2-year. Each simulated office building employs around 242 kWp to 387 kWp of maximum power outputs in the installation of on-site PV power systems to enable NZEB balances. On a national scale, the daily on-site PV power generation within NZEBs can cover around 50% to 110% of total daily electricity used in office buildings depending on weather conditions. The peak difference of U.S. electricity demand typically occurs when solar radiation is at its highest. The peak differences from the actual U.S. electricity demand on the representative summer day show 9.8%, 4.9%, and 2.0% at 12 p.m. for 100%, 50%, and 20% of the U.S. NZEB stocks, respectively. Using EES within NZEBs, the peak differences are reduced and shifted from noon to the beginning of the day, including 7.7%, 3.9%, and 1.5% for each percentage U.S. NZEB stock. NZEBs tend to create the significant curtailment of the U.S. electricity demand profile, typically during the middle of the winter day. The percentage differences at a peak point (12 p.m.) are 8.3%, 4.2%, and 1.7% for 100%, 50%, and 20% of the U.S. NZEB stocks, respectively. However, using EES on the representative winter day can flatten curtailed electricity demand curves by shifting the peak difference point to the beginning and the late afternoon of the day. The shifted peak differences show 7.4%, 3.7%, and 1.5% at 9 a.m. for three U.S. NZEB stock scenarios, respectively.

Promoting and developing Zero Energy Buildings (ZEB) is crucial to achieving the goal of net-zero emissions. Zero Energy Buildings emphasize not only on buildings’ energy efficiency, but also on the transition of buildings’ energy consumption from nonrenewable energy to renewable energy. However, practically, since it is often impossible to achieve the “Zero” energy consumption in a strict sense, the concept of ZEB is implemented as Nearly Zero Energy Buildings (NZEB). Although adopting solar energy to achieve the goal of NZEB is currently one of the most feasible strategies, under what conditions the use solar energy for NZEB is technically feasible and how the building owners are motivated to invest in NZEB are still vague and challenging. As the solar power technology continues to advance and the environmental morality continues to rise in countries and societies, this study takes Taiwan as a case to study how feasible technically and behaviorally the NZEB is and what could be the main challenges.Through extensive literature review and expert interviews, we analyze and establish the standards for defining the NZEB in Taiwan. Then we categorize the building types and residential energy consumption scenarios in Taiwan and investigate different approaches to installing solar photovoltaic systems. In sum, the two main approaches to installing solar photovoltaic systems are the roof floor installation and the roof trellis installation. The types of buildings to be studied are the terrace houses, the five-story apartments, and the eight-story apartments. To simulate the net energy consumption, firstly, Ladybug Tools is used to simulate the annual power generation of each solar photovoltaic installation in different climatic regions in Taiwan. Secondly, the formula for calculating the photovoltaic power generation is proposed according to the simulation results. Lastly, we analyze whether each installation approach can meet the specifications of NZEB under different energy consumption scenarios and evaluate, accordingly, the technical feasibility of achieving the goal of NZEB.Based on the simulation, the roof trellis type is shown to generate the most power under the same construction area and to be the most feasible solar photovoltaic installation approach for the residential buildings to achieve NZEB.We also analyze the economic feasibility of different NZEB scenarios using NPV and IRR methods. It is shown that, except for the eight-story apartments in the northern Taiwan’s climatic region, the simulated NZEB scenarios are economically feasible. Among them, the NPVs of the roof trellis type are lower than other schemes, the investment costs are expected to be recovered in about 13 to 17 years, and the IRR is about 5 to 7% for terrace houses and five-story apartments. To conclude, based on the current/modern solar photovoltaic technologies, NZEB can be well achieved for the residential buildings if the housing owners choose to invest.Finally, whether the NZEB can be achieved depends on the house owners’ willingness to invest in NZEB, the main challenges of NZEB in Taiwan. We shall develop a consumer behavior model and form policy insights concerning NZEB.Acknowledgment: Grant number 111-2124-M-002-006 and Grant number 110-2221-E-002-

The conception of net zero energy buildings (NZEB) has been introduced to limit energy consumption and pollution emissions in buildings. Classification of NZEB is based on renewable energy (RE) supply options, energy measurement process, RE-sources location, and balances whether are energetic or exergetic. In general, it is traditionally agreed that there are three main steps to reach the NZEB performance, starting through the use of passive strategies, energy efficient technologies, and then RE generation systems. Then, these three steps could be accompanied with the smart integration of advanced efficient energy technologies. A state of the art shows that the main ZEB studies are related to: energy savings, reduce electric bills, energy independence, pollution reduction, and occupants comfort, in addition, others are more interested in the aesthetic aspect by combining modern technologies with innovations to achieve high energy and sustainability performance. Building optimization is a promising technique to evaluate NZEB design choices; it has been adopted to choose the perfect solution to reach the zero energy performance through the optimization of an objective function related to energy (thermal loads, RE generation, energy savings) and/or environment (CO2 emissions) and/or economy (life-cycle cost (LCC), net-present value (NPV), investment cost). This paper starts by presenting the global energetic and pollution challenges the world faces. Moreover, it shows, to the best to the author’s knowledge, the existing NZEB definitions and the corresponding case studies investigated in 8 different climatic zones (humid continental, humid subtropical, Mediterranean, moderate continental, moderate continental, marine west coast, tropical, semi-arid and hot), the paper also focus on the importance to treat each climate separately. Even in the same country, two or more climates may co-exist. NZEBs drawbacks are also presented. Furthermore, different optimization problems are reviewed in the last section. Building energy optimization methods are employed to obtain the ideal solution for specific objective functions which are either related to energy, and/or environment and/or economy. Optimization variables are distributed between passive and/or RE generation systems. Finally, a table summarizing the most commonly used electric and thermal RE applications which yield to the zero energy balance in each climate, as well as three flowcharts are presented to summarize the whole three-stage procedure, to reach NZEB, starting from building designing, passing through the optimization procedure, and lastly categorizing the zero energy balance.

Efforts have been put in place to minimize the effects of construction activities and occupancy, but the problem of greenhouse gas (GHG) emissions continues to have detrimental effects on the environment. As an effort to reduce GHG emissions, particularly carbon emissions, countable commercial, industrial, institutional, and residential net-zero energy (NZE) buildings were built around the globe during the past few years, and they are still operating. But there exist many challenges and barriers for the construction of NZE buildings. This study identifies the obstacles to developing NZE buildings, with a focus on single-family homes, in the Greater Toronto Area (GTA). The study sought to identify the technical, organizational, and social challenges of constructing NZE buildings, realize the importance of the public awareness in making NZE homes, and provide recommendations on how to raise public knowledge. A qualitative approach was employed to collect the primary data through survey and interviews. The secondary data obtained from the literature review were also used to realize the benefits, challenges, and current situation of NZE buildings. Research results indicate that the construction of NZE buildings is faced with a myriad of challenges, including technical issues, the lack of governmental and institutional supports, and the lack of standardized measures. The public awareness of NZE homes has been found to be very low, thus limiting the uptake and adoption of the new technologies used in this type of homes. The present study also recommends that the government and the academic institutions should strive to support the NZE building technology through curriculum changes, technological uptake, and financial incentives to buyers and developers. The implementation of these recommendations may enhance the success and popularity of NZE homes in the GTA.

Solar building architecture: edited by Bruce Anderson The MIT Press, Cambridge, MA, USA, 1990, 368pp, £35.95

A review of net zero energy buildings in hot and humid climates: Experience learned from 34 case study buildings

Decarbonising the energy sector is crucial to reach future climate and energy goals. As established by the Energy Performance of Building Directive recast, Nearly Zero Energy Buildings (NZEBs) are the mandatory building target in Europe for all new buildings from 2021 onwards. In the light of the approaching deadline, this paper assesses the development of NZEBs in Europe based on the most recent collected data and information.This paper provides an overview of the implementation of national definitions and energy performance values for new, existing, residential, and non-residential buildings in Member States. It evaluates the differences with the established European benchmark and cost-optimal levels. An overview of the most commonly implemented technologies in NZEBs is given together with costs and the relative projections over next decades. Finally, quantitative data on the NZEBs diffusion in Member States are given as recently assessed. The evolution of the NZEB concept and the future NZEBs role is also forecasted.The results assume a strategic value in the light of future targets for the building sector, showing the progress made by Member States in relation to different NZEBs aspects. They provide a comprehensive analysis of the European NZEBs implementation depicting a positive overall progress improvement for NZEBs definitions, uptake, technology development, and energy performance levels. Next challenges and barriers are outlined and appear mainly related to NZEBs retrofit.

In addition to policy target in Japan (ZEB (Zero Energy Building) is scheduled for new buildings on the average by 2030), the efforts to decarbonize corporate activities are accelerated and private needs of ZEB is growing after Paris Agreement. On the other hand, most of owners tend to be careful to invest in ZEB due to high cost to realize ZEB in general. With above background, we’re promoting ZEBs at the same cost as general buildings and have designed and built “Office-TS and Office-AI” as model projects of ZEB to meet such private needs of ZEB. Based on our policy to provide ZEB with a lot of owners by reasonable cost, economically ZEBs are realized with design of both comfort and ecology by optimum combination of general technologies with excellent cost –performance. Currently in general, most of other existing ZEBs are the demonstration projects implemented by Design or Construction Companies, therefore, it is very advanced examples to provide ZEBs with general private clients. “Approachable ZEB” which can be realized economically will contribute sustainable corporate activities of many owners and sustainable social foundation. In below actual two “Approachable ZEB” projects are introduce; Office-TS has set an energy-saving target of <Nearly ZEB > (more than 75% energy saving) and Office-AI <ZEB Ready> (more than 50% energy saving). Both are realized with the general technologies also with the same cost level as other general non-ZEB projects.

In India, construction is the second largest industry next to agriculture, with respect to its contribution to the economy of our country. Construction sector consumes a lot of energy throughout the life cycle of the buildings and contributes immensely to the emission of greenhouse gases like carbon dioxide. Considerable amount of water is being consumed during the construction activities. It is found that In-dia’s water table is decreasing, Hence, there is a need to bring down en-ergy consumption and conservation and harvesting of water by implementing green and zero energy concepts. Net zero energy building is defined as a building with zero dependence on external source of energy. The main aim of this study is “Planning, analyzing and designing a 5 floor apartment building by implementing zero energy concepts and techniques”. Planning has been carried out by taking into account, the orientation aspects. Planning and plotting of the structure has been car-ried out using AutoCAD. Further analysis is done in STAAD Pro V8i and Cype taking the design loads for both zero energy and conventional building. Energy saving components such as rainwater harvesting system, solar panels, biogas plant, and wind energy and sewage treat-ment plant have been implemented as per standards. The dependence on external energy source is reduced by making use of the alternative energy sources such as solar PV panels, biogas and wind turbine there by making it economical environmental friendly. Estimation of the materials based on the drawings and specifications is carried out. Lastly, a comparative study of conventional versus zero energy building is done by performing cost benefit analysis of solar panel system.By using rainwater harvesting system the water bills reduced by 27% annually and by installing a solar panel with a capacity of 233 Kw/h led to the energy savings by 20 % annually. Also from the cost estima-tion, the payback period for green building was approximately 2.9 years for solar power.

Purpose Despite the current attention on net zero energy buildings (NZEBs) and the renewable energy potential of developing economies, their potential in developing economies remains underutilized. This untapped opportunity is largely attributed to a lack of knowledge regarding effective NZEB implementation strategies. Therefore, this study investigates the strategies for the implementation of NZEBs in a developing economy. Design/methodology/approach The study used a mixed-methods approach, conducting a quantitative survey among 120 construction professionals and semi-structured interviews with 10 NZEB experts to develop a conceptual framework for NZEBs implementation in the Ghanaian construction industry (GCI). The quantitative data collected were analysed using mean scores, standard deviation, one-sample t-test and normalisation value (NV) test. The qualitative results were thematically analysed and compared with the quantitative findings to validate and enrich the interpretation through detailed insights from interviewees. Findings The findings highlighted seven key strategies critical to NZEB implementation in the GCI: creation of NZEB awareness among design professionals and contractors; academic institutions’ intervention; government promotion of NZEB awareness; specialist training in renewable energy technologies; educating building owners about energy-saving benefits; ensuring adequate experts for NZEB quality assurance and publicizing the health benefits of NZEBs. Originality/value The findings of this study shed light on a relatively under-reported area within the built environment of a developing country, particularly Ghana. This offers insights and contributes new and supplementary knowledge on strategies for implementing NZEBs.