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

Sustainable development in the building sector requires the integration of energy efficiency and renewable energy utilization in buildings. In recent years, the concept of net zero energy buildings (NZEBs) has become a potential plausible solution to improve efficiency and reduce energy consumption in buildings. To achieve an NZEB goal, building systems and design strategies must be integrated and optimized based on local climatic conditions. This paper provides a comprehensive review of NZEBs and their current development in hot and humid regions. Through investigating 34 NZEB cases around the world, this study summarized NZEB key design strategies, technology choices and energy performance. The study found that passive design and technologies such as daylighting and natural ventilation are often adopted for NZEBs in hot and humid climates, together with other energy efficient and renewable energy technologies. Most NZEB cases demonstrated site annual energy consumption intensity less than 100 kW-hours (kWh) per square meter of floor space, and some buildings even achieved “net-positive energy” (that is, they generate more energy locally than they consume). However, the analysis also shows that not all NZEBs are energy efficient buildings, and buildings with ample renewable energy adoption can still achieve NZEB status even with high energy use intensity. This paper provides in-depth case-study-driven analysis to evaluate NZEB energy performance and summarize best practices for high performance NZEBs. This review provides critical technical information as well as policy recommendations for net zero energy building development in hot and humid climates

Passive cooling of buildings with phase change materials using whole-building energy simulation tools: A review

Buildings contribute to climate change by consuming a considerable amount of energy to provide thermal comfort for occupants. Cooling energy demands are expected to increase substantially in the world. On this basis, technologies and techniques providing high energy efficiency in buildings such as passive cooling are highly appreciated. Passive cooling by means of phase change materials (PCM) offers high potential to decrease the cooling energy demand and to improve the indoor comfort condition. However, in order to be appropriately characterized and implemented into the building envelope, the PCM use should be numerically analyzed. Whole-building energy simulation tools can enhance the capability of the engineers and designers to analyze the thermal behavior of PCM-enhanced buildings. In this paper, an extensive review has been made, with regard to whole-building energy simulation for passive cooling, addressing the possibilities of applying different PCM-enhanced components into the building envelope and also the feasibility of PCM passive cooling system under different climate conditions. The application of PCM has not always been as energy beneficial as expected, and actually its effectiveness is highly dependent on the climatic condition, on the PCM melting temperature and on the occupants behavior. Therefore, energy simulation of passive PCM systems is found to be a single-objective or multi-objective optimization problem which requires appropriate mathematical models for energy and comfort assessment which should be further investigated. Moreover, further research is required to analyze the influence of natural night ventilation on the cooling performance of PCM.The work is partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER) and ENE2015-64117-C5-3-R (MINEDO/FEDER)). The authors would like to thank the Catalan Government for the quality accreditation g iven to their research group GREA (2014 SGR 123). This project has received funding from the European Commission Seventh Framework Program (FP/2007-2013) under Grant agreement Nº PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union’s Horizon 2020 research and innovation program under grant ag reement No 657466 (INPATH-TES). Alvaro de Gracia would like to thank Ministerio de Economia y Competitividad de España for Grant Juan de la Cierva, FJCI-2014-19940

Options for demonstrating the use of solar energy in california buildings

Three programmatic options for demonstrating the most economically attractive applications of solar energy to buildings located in California are formulated. The unique characteristics of solar energy demonstration programs and the involvement of key decision makers are discussed in detail. The demonstration programs are related to specific purposes. The priority structure used to select the generic projects making up each program is discussed in relationship to the purposes of the program. In addition, some implications of the nature of the demonstration program for management are outlined

Solar thermal heating and cooling. A bibliography with abstracts

This bibliographic series cites and abstracts the literature and technical papers on the heating and cooling of buildings with solar thermal energy. Over 650 citations are arranged in the following categories: space heating and cooling systems; space heating and cooling models; building energy conservation; architectural considerations, thermal load computations; thermal load measurements, domestic hot water, solar and atmospheric radiation, swimming pools; and economics

Porous materials in building energy technologies—a review of the applications, modelling and experiments

Improving energy efficiency in buildings is central to achieving the goals set by Paris agreement in 2015, as it reduces the energy consumption and consequently the emission of greenhouse gases without jeopardising human comfort. The literature includes a large number of articles on energy performance of the residential and commercial buildings. Many researchers have examined porous materials as affordable and promising means of improving the energy efficiency of buildings. Further, some of the natural media involved in building energy technologies are porous. However, currently, there is no review article exclusively focused on the porous media pertinent to the building energy technologies. Accordingly, this article performs a review of literature on the applications, modelling and experimental studies about the materials containing macro, micro, and nano-porous media and their advantages and limitations in different building energy technologies. These include roof cooling, ground-source heat pumps and heat exchangers, insulations, and thermal energy storage systems. The progress made and the remaining challenges in each technology are discussed and some conclusions and suggestions are made for the future research

Appropriateness’ of the use of tensile membrane structures in hot arid regions

Today, with the vast technological progress and the deep understanding of our environment, and the insisting need to reduce energy consumption to save our natural resources there have been a shift in thinking and the need for a sustainable environmentally friendly architecture has evolved. The need of new materials and structures that fulfil the occupant’s needs and comfort, has the architectural beauty and attraction and be environmentally friendly has become a necessity. Although, tensile membrane structures (TMS) are relatively new as a structural material, they have been widely used in many architectural projects that were mainly considered as architectural statements and landmarks. Form finding and structure analysis of such structures has become an established discipline, however, their environmental understanding and behaviour are still in its infancy. This paper considers the appropriateness of the use of TMS in hot arid regions through a review of some of the built environment successful built examples

CFD supported modelling of double skin facades in hot arid climates

Previous simulations predict the possibility of reducing cooling demands in office buildings in hot arid areas if a selective double skin facade is used. The reductions on cooling loads in rooms range between 19%-40% depending on the glazing thermal and visual performance characteristics of the exterior glazing of the double skin façade. However considerable uncertainty exists about the air flow rates and temperatures experienced within the channels of these facades. In this work a CFD model is used to predict these conditions for the case of an air-conditioned building in a hot arid climate. This case uniquely allows a CFD model to be applied to the facade independent of the simulation of the main building and its plant. Results show appreciable flow rates and temperatures generated mainly by buoyancy flow over the outer facade skin

Climate based facade design for business buildings with examples from central London

There is a disconnection between commercial architecture and environmental thinking, where green features can be included as part of a strategy for gaining approvals and marketing projects, but those features are not reviewed after completion and occupation of the building and knowledge is not shared. High levels of air conditioning are still considered unavoidable. Elaborate double skin façades and complex motorized shading systems are adopted; often masking an underlying lack of basic environmental thinking. This article returns (in principle) to the physics of comfort in buildings and the passive strategies which can help achieve this with a low energy and carbon footprint. Passive and active façade design strategies are outlined as the basis of a critical tool and a design methodology for new projects. A new architectural sensibility can arise based on modeling the inputs of sunlight, daylight and air temperature in time and space at the early stages of design. Early but sound strategies can be tested and refined using advanced environmental modeling techniques. Architecture and environmental thinking can proceed hand in hand through the design process

Renewable energy for Latium: looking for innovative technologies in PV and solar thermal field.

European METTTES Project, financed within the FP6-2005-INNOV-7 call, aimed to test a new methodology to encourage the launch of transnational collaborations technology based among European small and medium enterprises (SMEs) and/or research organizations, focusing its attention on regional technology demand, influenced by changes in regulations and standards and fostered by local incentives. METTTES considered European directives, national, regional and local measures (i.e. incentives, projects, etc.) potentially influencing companies’ behavior. In addition, METTTES has also taken into account the IPPC (Integrated Pollution Prevention and Control) Directive 96/61/EC, whose purpose is to achieve an integrated pollution prevention and control from the industrial activities. At the end of these analysis, METTTES derived the technology demand not from the needs of individual enterprises, but instead from the regional system. A certain number of Regional Demand Profiles (RDPs) on particular interesting industrial fields have been collected at European level; the documentation includes a comprehensive analysis and detailed presentation of current regional technology demands and forecasts as well as foresight regarding future demands triggered by legal requirements new administrative regulations or national environmental policy and BATs analysis. Each RDP document has been edited with the collaboration of local stakeholders and administrations and by auditing involving SMEs. Results of each RDP have been high quality Technology Requests (TRs) expressed by local companies which seek technological collaboration. For Latium Region this task has been performed by CNR in the sector of PV and solar thermal technologies