Search Results (1,063)

The three key design criteria for nearly zero-energy buildings (nZEBs) and climate-neutral buildings are minimizing energy use, ensuring high occupant comfort, and reducing environmental impact. Thermal comfort is one of the main components of indoor environmental quality (IEQ), strongly affecting occupants’ health, well-being, and productivity. As energy-efficiency requirements become more demanding, the appropriate selection of heating systems, their automated control, and the management of solar heat gains are becoming increasingly important. This study investigates the influence of two low-temperature radiant heating systems—underfloor and wall-mounted—and the use of Venetian blinds on perceived thermal comfort in a highly glazed public nZEB building located in a densely built urban area within a temperate climate zone. The assessment was based on the PMV (Predicted Mean Vote) index, commonly used in IEQ research. The results show that both heating systems maintained indoor conditions corresponding to comfort or slight thermal stress under steady state operation. However, during periods of strong solar exposure in the room without blinds, PMV values exceeded 2.0, indicating substantial heat stress. In contrast, external Venetian blinds significantly stabilized the indoor microclimate—reducing PMV peaks by an average of 50.2% and lowering the number of discomfort hours by 94.9%—demonstrating the crucial role of solar protection in highly glazed spaces. No significant whole-body PMV differences were found between underfloor and wall heating. Overall, the findings provide practical insights into the control of thermal conditions in radiant-heated spaces and highlight the importance of solar shading in mitigating heat stress. These results may support the optimization of HVAC design, control, and operation in both residential and non-residential nZEB buildings, contributing to improved occupant comfort and enhanced energy efficiency. Full article

With a key policy decision on the role of hydrogen boilers expected by 2026, the UK is at a strategic crossroads in implementing its Heat and Buildings Strategy. This study evaluates the relative advantages of hydrogen boilers and heat pumps in residential heating, focusing on their impact on national energy demand, which is a critical factor in achieving full decarbonisation by 2050. Using the End-state Decarbonisation Resource Analysis framework, this study demonstrates that electrification with widespread heat pumps could reduce current residential primary energy demand by over 53%, whereas a hydrogen boiler-dominant pathway could increase demand by 42%. When translated into generation and infrastructure requirements, the hydrogen pathway would demand significantly more resources than the heat pump alternative. Incorporating heat pumps into the electrification strategy would make the delivery of net-zero targets more achievable. Notably, heat pumps could deliver nearly six times higher economic benefits than hydrogen, while requiring only 67% of investment needed for additional generation assets. These findings support prioritising heat pumps over hydrogen boilers in the UK’s national residential decarbonisation strategy. Full article

Energy deficits have been a major challenge in Sub-Saharan Africa (SSA), particularly in Nigeria. Consequently, the integration of renewable energy (RE) is a crucial strategy for achieving energy transition goals and addressing climate change issues. Therefore, this article investigates the technical, energy, economic, and environmental impact of PV/Wind/BS/Converter, a standalone hybrid energy mix for electrifying a single-family residential building prototype in multi-regional parts of Nigeria. This study aims to examine the renewable energy potential of three locations using HOMER Pro. The results indicate that Kano exhibits the lowest economic performance indices, with a net present cost (NPC) of USD 32,212.52 and a cost of energy (COE) of USD 0.6072/kWh, followed by Anambra (NPC: USD 45,671.68; COE: USD 0.8609/kWh) and Lagos (NPC: USD 47,184.62; COE: USD 0.8706/kWh). Technically, this study shows that the higher the renewable potential of a site, the lower the energy cost and vice versa. The sensitivity cases of key energy parameters—including solar PV cost, wind turbine cost, wind speed, solar radiation, and inflation rate—were considered to compare multiple scenarios and assess renewable energy potential variability under certain decision-making conditions. Economically, the Kano system shows the feasible capital cost of the energy produced, replacement cost, and operation and maintenance cost (O&M) for wind turbines, compared to the nil cost for Anambra and Lagos. Environmentally, the energy systems revealed 100% renewable fractions (RFs) with zero emissions at the three sites under study, which can enhance Nigeria’s energy transition plan and help in achieving the Sustainable Development Goals. Integrating RE supports the successful implementation of the recommended energy policy strategies for Nigeria. Full article

In recent decades, energy efficiency policies have increasingly focused on reducing buildings’ energy use and improving their performance. However, by overlooking the entire life cycle of a building, a considerable portion of its environmental impact has indeed been kept out of the process. As a result, even leading buildings that have advanced toward Zero-Energy status may not that as innocent as promised by evaluating environmental impacts during their whole life. Consequently, a logical method for achieving nearly Zero Energy Buildings (nZEBs) involves implementing energy-efficient measures and proper materials throughout the entire life cycle of buildings. This paper is one of its first kinds that includes all building systems and materials embodied energy and cost to explore the possibility of creating nearly zero residential buildings through their life cycle. Life-cycle energy consumptions, life-cycle CO₂ emissions and life-cycle cost of nZEB retrofit packages for a five-storey, 20-apartment residential building in Ankara, Turkey were evaluated. The methodology couples dynamic simulation (DesignBuilder/EnergyPlus) with an EN 15978-aligned boundary (A1–A5, B, C). The study highlights the critical role of both operational and embodied energy and carbon emissions in the pursuit of nZEBs. The best nZEB package reduces primary energy by ~55% and life-cycle CO₂ by ~45% relative to the reference building over 50 years, while cost-optimal packages deliver 6–7% lower global cost. These findings demonstrate the effectiveness of life cycle assessment in measuring building environmental impact, the utilization of renewable energy, and the optimization of building materials in reducing energy consumption and emissions, providing a sustainable and cost-efficient approach to residential building design. Full article

This case study is an overview of architectural design solutions implemented in the construction of farming facilities and the technological processes necessary to support a sustainable farm that runs with nearly zero waste in a closed-loop system that functions with full energy independence. The research will thoroughly investigate the specific location and configuration of the farm units in the target area—providing an extensive description of all necessary building typologies and infrastructures. The text will provide a summary of the agricultural solutions implemented at the farm, which is located in the region of Vojvodina in the Republic of Serbia. This region consists mainly of fertile agricultural land and could be a template for further designs and innovations in sustainable farming. This case study concerns the design of a resilient and self-reliant farm complex that consists of multiple animal species (broilers, pigs, and cattle), including a biogas station. The study is meant to show that adjustments made in architectural design, variations in building typology, and smart urban planning can contribute significantly to the improvement of sustainability in agricultural practices. This case study demonstrates that investments in sustainable solutions not only benefit the environment but can also deliver significant economic returns for investors—thereby further stimulating growth and development in the field of sustainable agriculture. Full article

The United Kingdom’s (UK) retrofit revolution is at a crossroads and the efficacy of retrofit interventions is not solely a function of insulation thickness. To truly slash emissions and lift households out of fuel poverty, we must solve the persistent problem of thermal bridging (TB), i.e., the hidden flaws that cause heat to escape, dampness to form, and well-intentioned retrofits to fail. This review moves beyond basic principles to spotlight the emerging tools and transformative strategies to make a difference. We explore the role of advanced modelling techniques, including finite element analysis (FEA), in pinpointing thermal and moisture-related risks, and how emerging materials like vacuum-insulated panels (VIPs) offer high-performance solutions in tight spaces. Crucially, we demonstrate how an integrated fabric-first approach, guided by standards like PAS 2035, is essential to manage moisture, ensure durability, and deliver the comfortable, low-energy homes the UK desperately needs. Therefore, achieving net-zero targets is critically dependent on the systematic upgrade of the building envelope, with the mitigation of TB representing a fundamental prerequisite. The EnerPHit approach applies a rigorous fabric-first methodology to eliminate TB and significantly reduce the building’s overall heat demand. This reduction enables the use of a compact heating system that can be efficiently powered by renewable energy sources, such as solar photovoltaic (PV). Moreover, this review employs a systematic literature synthesis to critically evaluate the integration of TB mitigation within the PAS 2035 framework, identifying key technical interdependencies and research gaps in whole-house retrofit methodology. This article provides a comprehensive review of established FEA modelling methodologies, rather than presenting results from original simulations. Full article

Despite growing interest in positive-energy and net-zero-energy buildings (NZEBs), few studies have addressed the integration of biobased construction with building-integrated photovoltaics (BIPV) under hot–dry climate conditions, particularly in Morocco and North Africa. This study fills this gap by presenting a simulation-based evaluation of energy performance and renewable energy integration strategies for a residential building in the Fes-Meknes region. Two structural configurations were compared using dynamic energy simulations in DesignBuilder/EnergyPlus, that is, a conventional concrete brick model and an eco-constructed alternative based on biobased wooden materials. Thus, the wooden construction reduced annual energy consumption by 33.3% and operational CO₂ emissions by 50% due to enhanced thermal insulation and moisture-regulating properties. Then multiple configurations of the solar energy systems were analysed, and an optimal hybrid off-grid hybrid system combining rooftop photovoltaic, BIPV, and lithium-ion battery storage achieved a 100% renewable energy fraction with an annual output of 12,390 kWh. While the system incurs a higher net present cost of $45,708 USD, it ensures full grid independence, lowers the electricity cost to $0.70/kWh, and improves occupant comfort. The novelty of this work lies in its integrated approach, which combines biobased construction, lifecycle-informed energy modelling, and HOMER-optimised PV/BIPV systems tailored to a hot, dry climate. The study provides a replicable framework for designing NZEBs in Morocco and similar arid regions, supporting the low-carbon transition and informing policy, planning, and sustainable construction strategies. Full article

This study presents a well-to-wheel life-cycle assessment (WTW-LCA) comparing battery-electric heavy-duty trucks (BEVs) with conventional diesel trucks, utilizing real-world fleet data from Southern California’s Volvo LIGHTS project. Class 7 and Class 8 vehicles were analyzed under ISO 14040/14044 standards, combining measured diesel emissions from portable emissions measurement systems (PEMSs) with BEV energy use derived from telematics and charging records. Upstream (“well-to-tank”) emissions were estimated using USLCI datasets and the 2020 Southern California Edison (SCE) power mix, with an additional scenario for BEVs powered by on-site solar energy. The analysis combines measured real-world energy consumption data from deployed battery electric trucks with on-road emission measurements from conventional diesel trucks collected by the UCR team. Environmental impacts were characterized using TRACI 2.1 across climate, air quality, toxicity, and fossil fuel depletion impact categories. The results show that BEVs reduce total WTW CO₂-equivalent emissions by approximately 75% compared to diesel. At the same time, criteria pollutants (NO_x, VOCs, SO_x, PM_2.5) decline sharply, reflecting the shift in impacts from vehicle exhaust to upstream electricity generation. Comparative analyses indicate BEV impacts range between 8% and 26% of diesel levels across most environmental indicators, with near-zero ozone-depletion effects. The main residual hotspot appears in the human-health cancer category (~35–38%), linked to upstream energy and materials, highlighting the continued need for grid decarbonization. The analysis focuses on operational WTW impacts, excluding vehicle manufacturing, battery production, and end-of-life phases. This use-phase emphasis provides a conservative yet practical basis for short-term fleet transition strategies. By integrating empirical performance data with life-cycle modeling, the study offers actionable insights to guide electrification policies and optimize upstream interventions for sustainable freight transport. These findings provide a quantitative decision-support basis for fleet operators and regulators planning near-term heavy-duty truck electrification in regions with similar grid mixes, and can serve as an empirical building block for future cradle-to-grave and dynamic LCA studies that extend beyond the operational well-to-wheels scope adopted here. Full article

The transition to net-zero energy solutions in university campuses is essential for advancing sustainability and enhancing energy efficiency. This paper presents a mathematical optimization model for implementing net-zero energy strategies in Saudi Arabian universities, focusing on Imam Mohammad Ibn Saud Islamic University (IMSIU) as a case study. An administration building within IMSIU campus, using real operational data with daily peak loads of 900 kW, are analyzed to determine optimal configurations of renewable and storage systems. Simulation results show that optimally deploying a 3,500 kW photovoltaic array integrated with a 560 kW/2,800 kWh battery energy storage system can effectively meet building-level energy demands and achieve seasonal net-zero balance during both winter and summer periods. The model demonstrates a substantial reduction in grid dependency while promoting the integration of renewable energy resources, showing strong alignment with the targets of the Saudi Green Initiative and national pathways for accelerating renewable energy deployment and energy sustainability. The findings provide a scalable and replicable framework for universities seeking to transition toward net-zero readiness, promoting sustainability in higher education and supporting the broader national goal of carbon-neutral development. Full article

The cost of “carbon net zero by year 2050” for the UK will be high, and this target date can only be achieved if the project is undertaken in a progressive and timely manner; otherwise, costs will escalate. The base power source behind the UK approach to “net zero” is nuclear fission electricity power stations, and the ones currently on order are running significantly late. Renewables will provide some supply together with interconnectors, but only approx. twenty percent of the planned wind turbines are in place. The electricity distribution grid must change to satisfy the UK’s planned “electricity-based” future. Energy use for transport is also a significant fraction of total UK energy consumption and we include predictions for their associated emissions. These must be reduced in a progressive and timely fashion. Intermittent support for unreliable renewables is necessary and methods employing both liquid as well as gaseous fuels are suggested. Means to use and upgrade the existing infrastructure are considered, and a few of the basic building blocks of the future are examined regarding their installation without significant interruption to the basic UK economy. ANR/AMR and SMR are included as potential renewables support as well as base load generators, and the approx. quantity of CO₂e emissions avoided is estimated. Even though methane is a powerful greenhouse gas, the main support for renewables will be UK natural gas (methane content ~95%), with Avtur/diesel as a recommended reserve. It is suggested that methane has a significant short- to medium-term future as a transition fuel. Full article

This systematic review analyzed energy efficiency strategies in Latin American university buildings, with emphasis on highland climates. Following PRISMA guidelines, 225 documents were screened from Scopus, Web of Science, and Google Scholar, yielding 36 studies published between 2015 and 2025. Reported interventions achieved 10–40% energy savings (median 18.5%), annual cost savings of USD 5672–USD 218,426 per building, with substantial variation reflecting differences in building size, intervention scope, and technology selection and carbon mitigation of 79–497 tons CO₂e annually. Common measures included LED retrofits, building automation, and solar photovoltaics, while integrated approaches reached up to 60% savings but required longer payback periods. Only six studies validated simulations with field data, and six addressed highland climates, limiting regional applicability. Free modeling tools such as EnergyPlus and OpenStudio increased accessibility but faced adoption barriers due to steep learning curves and scarce documentation in Spanish and Portuguese. Key barriers included inadequate metering (53%), limited funding (61%), and policy gaps (53%), while enablers involved ISO 50001 adoption and strong institutional leadership. Overall, evidence remains fragmented, highlighting the need for integrated frameworks linking validated models, technology, governance, and regional collaboration. Full article

This research presents a solution to the problem of controlling the energy demand and carbon footprint of old buildings, with the focus being on a (heated) building located in Madrid, Spain. A framework that incorporates AI and advanced hybrid ensemble approaches to make very accurate energy consumption predictions was developed and tested using the MATLAB environment. At first, the study evaluated six individual AI models (ANN, RF, XGBoost, RBF, Autoencoder, and Decision Tree) using a dataset of 100 points that were collected from the building’s sensors. Their performance was evaluated with high-quality data, which were ensured to be free of missing values or outliers, and they were prepared using L1/L2 normalization to guarantee optimal model performance. Later, higher accuracy was achieved through combining the models by means of hybrid ensemble techniques (voting, stacking, and blending). The main contribution is the application of a Long Short-Term Memory (LSTM) model for predicting the energy consumption of the building and, very importantly, its carbon footprint over a 30-year period until 2050. Additionally, the proposed methodology provides a structured pathway for existing buildings to progress toward nearly Zero-Energy Building (nZEB) performance by enabling more effective control of their energy demand and operational emissions. The comprehensive assessment of predictive models definitively concludes that the blended ensemble method is the most powerful and accurate forecasting tool, achieving 97% accuracy. A scenario where building heating energy use jumps to 135 by 2050 (a 35% increase above 2020 levels) represents an alarming complete failure to achieve energy efficiency and decarbonization goals, which would fundamentally jeopardize climate targets, energy security, and consumer expenditure. Full article

To support national carbon neutrality goals, enhancing the thermal insulation of building envelopes has emerged as a crucial strategy in reducing building energy consumption. This study conducted a detailed quantitative analysis of energy performance improvements achieved through enhanced insulation levels in four representative non-residential building types: office, accommodation, educational, and sales facilities. Based on four scenarios—Baseline (2019), Insulation Reinforced, Passive House, and Zero Energy Building (ZEB)—EnergyPlus simulations were performed to calculate end-use energy demand and consumption. The results revealed that office buildings achieved the highest improvement, with up to 34.7% energy reduction, while educational and sales facilities showed moderate and limited improvements, respectively. These findings provide quantitative evidence for prioritizing insulation-based policies and differentiated ZEB strategies tailored to each building type. The proposed RB models and scenario-based methodology offer a robust foundation for establishing future ZEB regulations and performance-based energy policies in South Korea. To ensure clarity, the study explicitly referenced verified data sources and field measurements. The IdealLoadsAirSystem used in the simulation assumes 100% system efficiency; thus, the reported outcomes represent building system loads rather than final energy consumption. The ZEB-level scenario analyzed in this study focuses on envelope and lighting improvements only, not on HVAC system optimization. Full article

As a specialized recurrent neural network (RNN), the Zeroing Neural Network (ZNN) has demonstrated efficacy in solving diverse real-time, time-varying problems. This paper proposes a ZNN-based model framework to address the challenge of time-varying demand response within building energy management systems, specifically for thermo-electric integrated systems. The framework encompasses model construction, control design, performance analysis, and robustness testing. Results indicate that the system’s target power effectively adapts to real-time electricity pricing with minimal response latency. The ZNN controller achieves extremely low tracking error, with a maximum observed value of merely −1.38 kW. Furthermore, the system exhibits strong robustness against disturbances in the coefficient of performance (COP) and achieves lower tracking error with increased thermal storage tank heat capacity. The ZNN has significant performance advantages in time-varying demand response scenarios. Full article

Energy efficiency in buildings is a vital subject within sustainable construction and climate change mitigation, yet comprehensive bibliometric analyses mapping the complete evolution of this domain remain limited. This study provides a comprehensive four-decade analysis (1981–2025) of building energy efficiency research using data from the Web of Science database, employing VOSviewer (1.6.20), Bibliometrix (4.3.0), and custom Python (3.12.3) scripts with automated terminology normalization through TF-IDF vectorization (n-grams 2–3) and cosine similarity algorithms (threshold = 0.75). Two critical methodological innovations distinguish this investigation: first, Pruned Exact Linear Time changepoint detection statistically validated 2011 as the field’s statistically validated transition point (Mann–Whitney U test, p < 0.000001, effect size = 2.48), replacing arbitrary decade-based periodization; second, computational keyword harmonization enabled precise thematic evolution mapping across inconsistent terminology. The analysis reveals marked increase in research post-2011, with median annual output increasing from 15 articles (1981–2011) to 840.5 articles (2012–2024), and China emerging as the preeminent research center with 2978 publications. Thematic evolution analysis demonstrates fundamental transformation from seven specialized research themes (i.e., behavior, heat-transfer, simulation, impact, performance, consumption, optimization) in the foundational period to dramatic consolidation into two dominant themes (i.e., performance and simulation) in the contemporary period, reflecting maturation from fragmented, component-focused investigations toward holistic, integrated frameworks. International collaboration network analysis identifies four distinct geographic clusters with China, United States, United Kingdom, and Italy serving as central hubs. These findings provide actionable intelligence for researchers, policymakers, and industry stakeholders, while the computationally enhanced framework offers a replicable methodology for bibliometric analysis in other rapidly evolving interdisciplinary domains. Full article