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Toward net zero emissions by 2050, efficient renewable energy systems and various energy interactions are increasingly proposed to improve energy matching and flexibility capacities. The existing studies primarily focused on onshore solar and wind energy sources, which can interact with electric vehicles or static batteries to improve the economic performance by the energy flexibility control. However, the hybrid system of ocean energy interacting with buildings and electric boats is rarely discussed. This study proposes an innovative integrated energy flexibility control to improve the techno-economic performance of a hybrid wave energy converter (WEC) and floating photovoltaic panel (FPV) energy system supporting a coastal hotel building and eight electric boats. We propose five control strategies, guaranteeing the normal excursion function of the boats while supporting enough energy for the building. In addition, two new indicators are presented to investigate the peak-shaving (PSI) and valley-filling (VFI) capabilities. A weighted matching index (WMI) is provided to investigate the overall energy matching capability. Annual electricity fees and relative net present value (NPVrel) are introduced to analyse the economy. To analyse the environmental aspect, we use the annual operational equivalent CO2 emissions (CEa) to track the emissions of the hybrid system. We observe that strategy E, integrated with the non-dominated solutions from the other four strategies, shows a significant profitable economic performance The annual electricity fee is reduced by 12.22%, and the NPVrelis improved by around 16.62%. PSI and VFI can reach 98.01% and 17.05% for a 100 kW line.

A building-integrated photovoltaic (BIPV) system produces power using photovoltaic (PV) modules as building exterior materials, whose architectural performance serves the same functions as those of existing building materials. Most relevant studies targeted general PV modules used in the building-mounted and -attached types. This study aims to integrate the building elevation-type BIPV system and exterior materials to secure both exterior material performance and PV electrical performance by embedding a power optimization device in an integrated system of BIPV modules and exterior materials. Thus, the advantages of economy, safety, aesthetics, and ease of maintenance can be achieved. In this study, experiments were conducted on elevation-type BIPV modules with and without a power optimizer, that is, a DC/DC converter, under various shade conditions, and the power loss rate of the BIPV system was analyzed. The power optimizer-equipped BIPV system was experimentally observed to have a PV power-loss rate approximately 2–3 times lower than that of the BIPV system without a power optimizer when the shade ratio of one module was approximately 10–75%. This exterior material-integrated BIPV-specific power optimization device reduces dependence on fossil fuels for power production and improves energy sustainability, contributing to the spread of zero-energy buildings and carbon neutrality.

The transition to a net-zero energy system is being promoted in the energy sector, which has led to the creation of energy prosumers. These produce, consume, and trade energy using renewable energy systems installed in buildings or complexes. Here, a community was set as the target to apply the concept of an energy prosumer at the individual building and regional levels. Energy-sharing systems were divided into three categories: energy production, energy storage, and energy management. Energy-sharing systems centered on electrical energy—photovoltaic, battery energy storage, and energy management systems—were installed in two communities located in South Korea, and the energy-sharing effects of the system operation were reported. Monthly power consumption in spring and fall exhibited significant savings of approximately three times that of winter consumption, owing to the energy-sharing systems. Daily hourly power-consumption patterns differed on weekdays and weekends because of the weekday working and building-use hours of the communities. Energy could be shared between communities and buildings because of surplus energy. More surplus power was available for energy sharing on weekends because power consumption was lower. Because energy trading and sharing are restricted, the related laws are being revised. Therefore, a low-carbon community can be realized through surplus energy trading and sharing technology between communities and buildings as renewable energy systems spread owing to low carbonization.

The energy consumption in buildings is increasing, then, a new global multiple-objective optimization method for zero-energy buildings with the comprehensive assessment method is used in this study. The applied optimization design methods for renewable energy systems are the multiple-objective optimization by Enhanced Archimedes Optimization Algorithm (EAOA) on the original design for energy costs and energy optimal models. The Hybrid Gray Multiple-Level Comprehensive Assessment Method (HGMLCAM) is utilized to the optimal model including the solar energy use efficacy, energy conservation, economic and social factors. By the selected decision based on the global optimal model, the best solution is presented. For designing the practical building, the defined solution can be useful for the architects and decision-makers. Consequently, a multiple-objective design for a building located in Shanghai, in China, is studied. Based on the results, it can be concluded that the presented method is efficient to make decisions.

Solar power systems, such as photovoltaic (PV) systems, have become a necessary feature of zero-energy buildings because efficient building design and construction materials alone are not sufficient to meet the building’s energy consumption needs. However, solar power generation is subject to fluctuations based on weather conditions, and these fluctuations are higher than other renewable energy sources. This phenomenon has emphasized the importance of predicting solar power generation through weather forecasting. In this paper, an Automatic Machine Learning (AML)-based method is proposed to create multiple prediction models based on solar power generation and weather data. Then, the best model to predict daily solar power generation is selected from these models. The solar power generation data used in this study was obtained from an actual solar system installed in a zero-energy building, while the weather data was obtained from open data provided by the Korea Meteorological Administration. In addition, To verify the validity of the proposed method, an ideal data model with high accuracy but difficult to apply to the actual system and a comparison model with a relatively low accuracy but suitable for application to the actual system were created. The performance was compared with the model created by the proposed method. Based on the validation process, the proposed approach shows 5–10% higher prediction accuracies compared to the comparison model.

The exploitation of renewable energy sources in the building sector is a challenging aspect of achieving sustainability. The incorporation of a proper storage unit is a vital issue for managing properly renewable electricity production and so to avoid the use of grid electricity. The present investigation examines a zero-energy residential building that uses photovoltaics for covering all its energy needs (heating, cooling, domestic hot water, and appliances-lighting needs). The building uses a reversible heat pump and an electrical heater, so there is not any need for fuel. The novel aspect of the present analysis lies in the utilization of hydrogen as the storage technology in a power-to-hydrogen-to-power design. The residual electricity production from the photovoltaics feeds an electrolyzer for hydrogen production which is stored in the proper tank under high pressure. When there is a need for electricity, and the photovoltaics are not enough, the hydrogen is used in a fuel cell for producing the needed electricity. The present work examines a building of 400 m2 floor area in Athens with total yearly electrical demand of 23,656 kWh. It was found that the use of 203 m2 of photovoltaics with a hydrogen storage capacity of 34 m3 can make the building autonomous for the year period.

Nearly zero-energy-consumption buildings are the inevitable trend of future buildings. There have been a large number of studies on nearly zero building technology issues. However, there is no detailed study on how to effectively promote the development of nearly zero-energy consumption buildings according to China’s national conditions. Here, by establishing an evolutionary game model, this paper discusses the dynamic game scheme selection and stability strategy of three stakeholders, namely local government, real estate companies, and construction consumers, related to the development of nearly zero-energy-consumption buildings in the development process. The conditions required for evolutionary stabilization strategies were identified. Finally, Matlab data simulation analysis is used to further illustrate the stability and equilibrium strategies of each subject and the sensitivity analysis of the main influencing factors at various stages in the development process of nearly zero-energy-consuming buildings. The research results show that the government plays a leading role in the early stage of the development of nearly zero-energy consumption buildings, and as the market matures, government intervention gradually withdraws from the market; furthermore, if the cost of supervision is prohibitively high, the government’s willingness to supervise the market will be reduced. This will hinder consumers and developers from choosing nearly zero-energy-consuming buildings and if the penalties and subsidies are too low, it will be meaningless to the evolution of the optimal solution of the three parties. On this basis, targeted promotion programs are established to realize the rapid development of China’s nearly zero-energy-consumption building sector. Our research results can provide important scientific basis for the development of the nearly zero-energy building industry in China.

With the development of a low-carbon economy, zero-energy structures will become prevalent and take center stage in the construction industry. This paper uses the CiteSpace software to create knowledge maps of authors, institutions and keywords, and then examined and commented on research publications regarding zero-energy buildings in order to understand the research state and development trends of zero-energy buildings. The findings demonstrate that: (1) Since its inception in 2000, research on zero-energy buildings has advanced significantly; (2) A subject analysis approach is used to identify development trends and research emphasis, and the four research areas with the most papers published are energy fuels, construction building technology, civil engineering and green sustainable science technology; (3) China, the United States and Italy are the countries with the most activity in zero-energy building research; (4) Out of the eight most prominent keywords for the study subjects, the design of zero-energy buildings, the estimation of the carbon emissions of zero-energy buildings, the technical challenges of zero-energy buildings and the follow-up energy-saving measures of zero-energy buildings are the four fundamental topics covered in the most cited papers; (5) There are three obstacles to the development of zero-carbon buildings: unclear standards, immature technology and insufficient development momentum. The following three problems should receive more attention in the future: how to develop a widely accepted zero-carbon building standard; how to coordinate national support to achieve technological breakthroughs; and the establishment of an effective incentive mechanism at the international and national levels to promote the development of zero-carbon buildings.

This study aims to institutionalize an evaluation methodology to assess water-source heat pumps (WSHPs) when designing a zero-energy building. Thus, regions where zero-energy buildings were designed were subdivided into 66 sub-regions, thereby standardizing the temperatures on the source side of WSHPs using river water and pipeline water. Based on these data, ground-source and water-source heat pump system-based simulation (new and renewable energy self-sufficiency rate compared to building energy consumption) values were derived for cases whose condition (region or heat source) was different among the buildings certified as zero-energy buildings. The application of the standard meteorological data and reference hydrothermal data to the ECO2 program and outcome evaluation led to the following findings: in all cases (reference: Seoul), ground-source heat pumps (GSHPs) showed a higher self-sufficiency rate than WSHPs (ground source > pipeline water > river water). The self-sufficiency rate of GSHPs was 11–33% higher than that of WSHPs. In a regional comparison among the cold (Jeongseon), central (Seoul), and southern (Jeju Island) regions, WSHPs exhibited higher energy self-sufficiency rates than GSHPs under the conditions of higher water temperatures in winter and lower water temperatures in summer, as in the southern region.

Energy sharing is critical for zero-energy buildings on the community level. However, most existing works studied the energy sharing problems without considering the physical energy sharing circuit. In this paper, we provide a new perspective to explore the energy sharing among building with a specific energy sharing circuit, and then, the modeling, control, and verification of the energy sharing system are presented. The energy sharing system is modeled as a cyber-physical system, where the physical layer characterizes the physical energy sharing circuit, and the cyber layer represents the communication topology among buildings. In the control layer, an average state-of-charge (SoC) estimator is designed for energy storage systems (ESSs) of each building using the dynamic consensus protocol, and a cooperative SoC tracking law is designed to achieve the SoC balancing of ESSs. The closed-loop model of the energy sharing system is developed using the block diagram. A laboratory prototype is built to verify the effectiveness of the proposed energy sharing method. The experimental results verify that the proposed energy sharing system can achieve energy sharing among ESSs effectively and efficiently.

Following the Paris Agreement in 2015, the worldwide focus on global warming countermeasures has intensified. The Japanese government has declared its aim at achieving carbon neutrality by 2050. The concept of zero-energy buildings (ZEBs) is based on measures to reduce energy consumption in buildings, the prospects of which are gradually increasing. This study investigated the annual primary energy consumption; as well as evaluated, renewed, and renovated buildings that had a solar power generation system, and utilized solar and geothermal heat. It further examines the prospects of hydrogen production from on-site surplus electricity and the use of hydrogen fuel cells. A considerable difference was observed between the actual energy consumption (213 MJ/m2), and the energy consumption estimated using an energy simulation program (386 MJ/m2). Considerable savings of energy were achieved when evaluated based on the actual annual primary energy consumption of a building. The building attained a near net zero-energy consumption considering the power generated from the photovoltaic system. The study showed potential energy savings in the building by producing hydrogen, using surplus electricity from on-site power generation, and introducing hydrogen fuel cells. It is projected that a building’s energy consumption will be lowered by employing the electricity generated by the hydrogen fuel cell for standby power, water heating, and regenerating heat from the desiccant system.

According to the previous pieces of research, the building sector consumes about 40 % of total yield energy and produce one-third of GHG pollution emission. This point shows the significant potential in two aspects of energy optimization and pollution reduction in this field. The purpose of this research as a case study is to construct a residential building and develop the paths for reaching a zero-energy building, considering GHG emissions in the climate of Tehran, Iran. In thirty scenarios of this study, solar panels, solar water heaters, ground source heat pumps, and combined heat and power generators were selected to provide the required power and energy in the building. All three passive, single active, and hybrid active scenarios were defined and analyzed with respect to technical and economic factors. In all of the defined scenarios, the conditions are two-folded: (a) considering the effect of national profits, fuel saving, and pollution reduction and (b) without considering them so that the results would become more realistic. In the end, three different types of conclusions were made with respect to macro-engineering, energy, and economic perspectives. Statistical conclusions based on a questionnaire filled by 50 people and the perspective of achieving NZEB definition are presented.

Achieving the best energy performance has become an important goal. The European Union has consequently developed legislative measures that introduce the concepts of nearly zero-energy buildings and cost-effectiveness during life-cycle. We use these concepts, looking for the design of energy-efficient wineries, while reducing wine production costs. The research method is based on the monitoring of temperature and humidity of 12 red wine aging rooms of representative construction designs with almost zero energy consumption that together with the economic data obtained from construction cost update, determine a parameter that has been called “construction effectiveness”. This parameter allows the evaluation of the cost–benefit ratio of each of the analyzed constructions. The results obtained demonstrate that adequate conditions can be achieved for the wine aging with zero-energy buildings, although there are notable differences in cost, damping effectiveness, and resulting hygrothermal environment depending on the type of building. The correlation between performance and construction costs shows large differences in cost per unit of damping achieved: 0.5–2.7 €/m2 for temperature and 0.6–5 €/m2 for relative humidity. With a correct design, the differences between typologies can be reduced or even non-existent. The results obtained can be a valuable tool to promote the design of zero-energy warehouses.

The objective of this study is to derive a design methodology for a zero-energy building considering the energy production and consumption of the building. In order to establish the design methodology, various factors affecting the energy production and consumption of the building are derived, and the effect of the heat transmission rate, the surface to volume ratio (S/V ratio), the location and the orientation of the building are analyzed by simulation method. As a result, the S/V ratio and the heat transmission rate are the most important factors in the central region of Korea where consumes large amounts of heating and cooling energy. This is because the final energy consumption varies depending on the heat loss through the envelope. It was confirmed that solar power generation is the most important factor in the southern regions of Korea where the energy consumption is relatively small. The final energy consumption varies depending on the solar power generation in these areas. Therefore, when designing a zero-energy building, the zero-energy of the building can be achieved by using the design methodology established in this study.

Buildings that are designed with aggressive energy performance targets are defined broadly in this study as high-performance buildings. As the technology advances, some of these buildings have the potential to become zero-energy ready through the adoption of cost-effective measures, such as retro-commissioning and occupant behavior techniques. This study demonstrated the viability of an office building to achieve the zero-energy goal and intended to engage the owners of similar facilities. The case building was designed as a very low-energy building with an energy use intensity (EUI) goal of 42 kWh/(m2 a), and the actual EUI was 23.9 kWh/(m2 a). The calibrated simulation approach was employed in the study, and the results indicated that the case building can achieve the zero-energy goal by optimizing the controls of the HVAC (Heating, Ventilation and Air Conditioning) system, changing the occupant behavior and improving the performance of the photovoltaic system.