scholarly journals Exploring Climate-Change Impacts on Energy Efficiency and Overheating Vulnerability of Bioclimatic Residential Buildings under Central European Climate

2021 ◽  
Vol 13 (12) ◽  
pp. 6791
Author(s):  
Luka Pajek ◽  
Mitja Košir

Climate change is expected to expose the locked-in overheating risk concerning bioclimatic buildings adapted to a specific past climate state. The study aims to find energy-efficient building designs which are most resilient to overheating and increased cooling energy demands that will result from ongoing climate change. Therefore, a comprehensive parametric study of various passive building design measures was implemented, simulating the energy use of each combination for a temperate climate of Ljubljana, Slovenia. The approach to overheating vulnerability assessment was devised and applied using the increase in cooling energy demand as a performance indicator. The results showed that a B1 heating energy efficiency class according to the Slovenian Energy Performance Certificate classification was the highest attainable using the selected passive design parameters, while the energy demand for heating is projected to decrease over time. In contrast, the energy use for cooling is in general projected to increase. Furthermore, it was found that, in building models with higher heating energy use, low overheating vulnerability is easier to achieve. However, in models with high heating energy efficiency, very high overheating vulnerability is not expected. Accordingly, buildings should be designed for current heating energy efficiency and low vulnerability to future overheating. The paper shows a novel approach to bioclimatic building design with global warming adaptation integrated into the design process. It delivers recommendations for the energy-efficient, robust bioclimatic design of residential buildings in the Central European context, which are intended to guide designers and policymakers towards a resilient and sustainable built environment.

2021 ◽  
Vol 11 (9) ◽  
pp. 3972
Author(s):  
Azin Velashjerdi Farahani ◽  
Juha Jokisalo ◽  
Natalia Korhonen ◽  
Kirsti Jylhä ◽  
Kimmo Ruosteenoja ◽  
...  

The global average air temperature is increasing as a manifestation of climate change and more intense and frequent heatwaves are expected to be associated with this rise worldwide, including northern Europe. Summertime indoor conditions in residential buildings and the health of occupants are influenced by climate change, particularly if no mechanical cooling is used. The energy use of buildings contributes to climate change through greenhouse gas emissions. It is, therefore, necessary to analyze the effects of climate change on the overheating risk and energy demand of residential buildings and to assess the efficiency of various measures to alleviate the overheating. In this study, simulations of dynamic energy and indoor conditions in a new and an old apartment building are performed using two climate scenarios for southern Finland, one for average and the other for extreme weather conditions in 2050. The evaluated measures against overheating included orientations, blinds, site shading, window properties, openable windows, the split cooling unit, and the ventilation cooling and ventilation boost. In both buildings, the overheating risk is high in the current and projected future average climate and, in particular, during exceptionally hot summers. The indoor conditions are occasionally even injurious for the health of occupants. The openable windows and ventilation cooling with ventilation boost were effective in improving the indoor conditions, during both current and future average and extreme weather conditions. However, the split cooling unit installed in the living room was the only studied solution able to completely prevent overheating in all the spaces with a fairly small amount of extra energy usage.


Author(s):  
Hugo Hens

Since the 1990s, the successive EU directives and related national or regional legislations require new construction and retrofits to be as much as possible energy-efficient. Several measures that should stepwise minimize the primary energy use for heating and cooling have become mandated as requirement. However, in reality, related predicted savings are not seen in practice. Two effects are responsible for that. The first one refers to dweller habits, which are more energy-conserving than the calculation tools presume. In fact, while in non-energy-efficient ones, habits on average result in up to a 50% lower end energy use for heating than predicted. That percentage drops to zero or it even turns negative in extremely energy-efficient residences. The second effect refers to problems with low-voltage distribution grids not designed to transport the peaks in electricity whensunny in summer. Through that, a part of converters has to be uncoupled now and then, which means less renewable electricity. This is illustrated by examples that in theory should be net-zero buildings due to the measures applied and the presence of enough photovoltaic cells (PV) on each roof. We can conclude that mandating extreme energy efficiency far beyond the present total optimum value for residential buildings looks questionable as a policy. However, despite that, governments and administrations still seem to require even more extreme measurements regarding energy efficiency.


2019 ◽  
Vol 23 (3 Part B) ◽  
pp. 2071-2084 ◽  
Author(s):  
Norbert Harmathy ◽  
Danijela Urbancl ◽  
Darko Goricanec ◽  
Zoltán Magyar

The research elaborates various solutions using detailed economic evaluation and energy efficiency calculation and simulation technology for formulating applicable, energy and cost-efficient retrofit solutions of single-family residential buildings located in temperate climate areas. Primarily the annual energy demand for a reference existing single-family residential building was determined. The economic analysis was performed for six formulated refurbishment scenarios in order to determine which of the scenarios will demonstrate optimal performance both in energy and cost efficiency. A feasibility study was performed for the most efficient scenario, which included an economic evaluation of low temperature radiant heating systems were three energy suppliers (oil, natural gas and electricity for air to water heat pump) were compared. According to financial analyses the optimal scenario includes the replacement of windows, installation of 15 cm expanded polystyrene thermal insulation, low temperature radiant floor heating, with a payback period of ten years.


Buildings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 642
Author(s):  
Mark Kyeredey Ansah ◽  
Xi Chen ◽  
Hongxing Yang

Reducing the lifecycle energy use of buildings with renewable energy applications has become critical given the urgent need to decarbonize the building sector. Multi-objective optimizations have been widely applied to reduce the operational energy use of buildings, but limited studies concern the embodied or whole lifecycle energy use. Consequently, there are issues such as sub-optimal design solutions and unclear correlation between embodied and operational energy in the current building energy assessment. To address these gaps, this study integrates a multi-objective optimization method with building energy simulation and lifecycle assessment (LCA) to explore the optimal configuration of different building envelopes from a lifecycle perspective. Major contributions of the study include the integrated optimization which reflects the dynamics of the whole lifecycle energy use. Insights from the study reveal the optimal configuration of PV and composite building façades for different regions in sub-Saharan Africa. The lifecycle energy use for the optimized building design resulted in 24.59, 33.33, and 36.93% energy savings in Ghana, Burkina Faso, and Nigeria, respectively. Additionally, PV power generation can efficiently cover over 90% of the total building energy demand. This study provides valuable insights for building designers in sub-Saharan Africa and similar areas that minimize lifecycle energy demand.


2021 ◽  
Vol 1203 (2) ◽  
pp. 022020
Author(s):  
Yalim Gültekin

Abstract Greenhouse gas (GHG), which is a determining factor in climate change is a result of human activities, namely climate change is human-caused (anthropogenic). Cities, where 60% of the world's population of approximately 7.3 billion living today, are responsible for 60-80% consumption of energy, which is the lifeblood of intense human activities, thus at least 70% of GHG. Nevertheless, cities are the cause of climate change and other global environmental problems, as well as the innovation centres and laboratories to deal with their impact. With climate change becoming more explicit and active in the 21st century, researchers, governments and international institutions question cities’ strength/vulnerability against these problems, especially their energy production and consumption patterns that cause GHG, and they anticipate that urban resilience be the motivating force for urban policies. The widespread and effective use of renewable energy is regarded as an influential tool against climate change. However, this should be endorsed by spatial strategies. In the light of this approach, this study evaluates the urban form, building design and production technologies that are focused on energy efficiency and renewable energy use.


2020 ◽  
Vol 172 ◽  
pp. 02009
Author(s):  
André Badura ◽  
Birgit Mueller ◽  
Ivo Martinac

Large and rapid climatic changes can be uncomfortable and sometimes hazardous to humans. Buildings protect people from external climatic conditions, and also mitigate the impacts of external climate extremes through their design and construction, as well as with the help of dedicated building service and other technical systems. Active space conditioning accounts for more than 30 per cent of the overall final energy use in Germany. In the life cycle of a building, the construction phase (planning and construction) is the phase with the shortest duration. However, the quality applied during this phase has a significant impact on the resources required, as well as the overall building performance during the much longer operational phase. Once built, buildings are often unable to adapt to boundary conditions that were not considered in the original building design. Consequently, changing outdoor climate conditions can result in an uncomfortable indoor climate over the lifetime of a building. The aim of this study was to determine the effectiveness of flexible solutions for reducing winter heating loads and to reducing/avoiding summer cooling loads in nonresidential buildings in Germany. Various external shading scenarios for non-residential buildings were analysed using the IDA ICE indoor climate and energy simulation tool. Key simulation parameters included the orientation and location of the building, as well as the envelope structure. We investigated the impacts of solar shading on heat storage in the building mass and indoor climate and how different types of envelopes affect overall energy use. The result shows that the use of an adaptive building envelope allows a higher reduction of the total energy demand by 7 % to 15 % compared to an increase in insulation thickness only.


Buildings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 255
Author(s):  
Muataz Dhaif ◽  
André Stephan

In hot and humid climatic conditions, cooling tends to dominate building thermal energy use. Cooling loads can be reduced through the adoption of efficient building envelope materials, such as Structural Insulated Panels (SIPs). This study quantifies the life cycle cost and operational energy of a representative case-study house in Bahrain using SIPs and hollow concrete blocks (HCBs) for the envelope over a period of 50 years. Operational energy is calculated using a dynamic energy simulation tool, operational costs are calculated based on the energy demand and local tariff rates, and construction costs are estimated using market prices and quotations. The life cycle cost is quantified using the Net Present Cost technique. Results show that SIPs yield a 20.6% reduction in cooling energy use compared to HCBs. For SIP costs of 12 and 17 USD/m², the SIP house was cheaper throughout, or had a higher capital cost than the HCB house (breaking even in year 33), respectively. We propose policy recommendations with respect to material pricing, electricity tariffs, and energy efficiency, to improve the operational energy efficiency of houses in Bahrain and similar countries along the Arabian Peninsula.


Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 5061
Author(s):  
Raluca Buzatu ◽  
Viorel Ungureanu ◽  
Adrian Ciutina ◽  
Mihăiţă Gireadă ◽  
Daniel Vitan ◽  
...  

The building sector continues to register a significant rise in energy demand and environmental impact, notably in developing countries. A considerable proportion of this energy is required during the operational phase of buildings for interior heating and cooling, leading to a necessity of building performance improvement. A holistic approach in building design and construction represents a step to moderate construction costs in conjunction with reduced long-term operating costs and a low impact on the environment. The present paper presents an experimental evaluation of the energy efficiency of a building under real climate conditions; the building, which represents a holistically designed modular laboratory, is located in a moderate continental temperate climate, characteristic of the south-eastern part of the Pannonian Depression, with some sub-Mediterranean influences. Considerations for the holistic design of the building, including multi-object optimization and integrated design with a high regard for technology and operational life are described. The paper provides a genuine overview of the energy efficiency response of the building during six months of operational use through a monitored energy management system. The energetic analysis presented in the paper represents an intermediary stage as not all the energetic users were installed nor all the energetic suppliers. However, the results showed a reliable thermal response in the behaviour of recycled-PET thermal wadding used as insulation material in the building and for the intermediary stage in which the building has only secondary energy users, the energetic balance proves its efficiency, keeping the buffer stock of energy high values over 90%.


Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6170
Author(s):  
Jakob Carlander ◽  
Bahram Moshfegh ◽  
Jan Akander ◽  
Fredrik Karlsson

12.9% of the energy use in the EU originates from the commercial and public sector. It has therefore become a priority to optimize energy efficiency in these buildings. The purpose of this study has been to explore how energy demand in a new office building is affected by different internal heat gains, location, orientation, and façade design, and also to see how different indicators can change perspective on energy efficiency. The study was performed with simulations in IDA-ICE with different façade design and changes in internal heat gains (IHG), orientation, and location. Energy demand was then compared to two different indicators. Using a façade designed to lower solar heat gains had little effect on energy demand in the north of Sweden, but slightly more effect further south. The amount of internal heat gains had significant effect on energy demand. Making deeper studies on design and internal heat gains should therefore be prioritized in the beginning of new building projects so the most energy-efficient design can be chosen. When the indicator kWh/m2 was used, the cases with low internal heat gains were perceived as the most energy efficient, while when kWh/(m2 × hpers) (hpers = hours of use) was used, the cases with high occupancy and low electricity use were considered to be the most energy efficient. Therefore, revising the standardized indicator is of great importance.


Author(s):  
O. A. Omitaomu ◽  
B. L. Bhaduri ◽  
C. S. Maness ◽  
J. B. Kodysh ◽  
A. M. Noranzyk

Energy efficiency is the lowest cost option being promoted for achieving a sustainable energy policy. Thus, there have been some innovations to reduce residential and commercial energy usage. There have also been calls to the utility companies to give customers access to timely, useful, and actionable information about their energy use, in order to unleash additional innovations in homes and businesses. Hence, some web-based tools have been developed for the public to access and compare energy usage data. In order to advance on these efforts, we propose a data analytics framework called Citizen Engagement for Energy Efficient Communities (CoNNECT). On the one hand, CoNNECT will help households to understand (i) the patterns in their energy consumption over time and how those patterns correlate with weather data, (ii) how their monthly consumption compares to other households living in houses of similar size and age within the same geographic areas, and (iii) what other customers are doing to reduce their energy consumption. We hope that the availability of such data and analysis to the public will facilitate energy efficiency efforts in residential buildings. These capabilities formed the public portal of the CoNNECT framework. On the other hand, CoNNECT will help the utility companies to better understand their customers by making available to the utilities additional datasets that they naturally do not have access to, which could help them develop focused services for their customers. These additional capabilities are parts of the utility portal of the CoNNECT framework. In this paper, we describe the CoNNECT framework, the sources of the data used in its development, the functionalities of both the public and utility portals, and the application of empirical mode decomposition for decomposing usage signals into mode functions with the hope that such mode functions could help in clustering customers into unique groups and in developing guidelines for energy conservation.


Sign in / Sign up

Export Citation Format

Share Document