Energy Demand Reduction in Nearly Zero-Energy Buildings by Highly Efficient Aluminium Foam Heat Exchangers

2018 ◽  
Vol 919 ◽  
pp. 236-245
Author(s):  
Jaroslav Jerz ◽  
František Simančík ◽  
Ján Španielka ◽  
Jozef Šebek ◽  
Jaroslav Kováčik ◽  
...  

The capability periodically to store and release the latent heat of phase transition during melting and solidification of Phase Change Materials (PCMs) has been currently the main subject of interest with regard to cost reduction efforts for cooling, heating of interiors and Domestic Hot Water (DHW) necessary for the operation and maintenance of adequate thermal comfort in new modern as well as old renovated residential buildings. The main principle of PCMs facilities to reduce significantly the energy consumption in the building industry of the future is based on the ability of thermo-active heat exchangers to absorb and later to dissipate into the surroundings excessive heat which can be easily obtained from renewable sources (e.g. solar energy, geothermal heat, etc.) directly in a building or in its immediate vicinity. Smart interior tiling and furnishing systems can provide high energy efficiency by stabilizing the room temperature at a level ensuring sufficient thermal comfort basically governed by the thermal conductivity and heat exchange area between ceiling (respectively also wall and floor if necessary) heat exchangers (radiators) and the heat storage medium in the form of PCMs. Unfortunately, most conventional building materials, e.g. aerated concrete, bricks, gypsum, ceramic tiles, etc. are particularly characterized by very low thermal conductivity, which disadvantages them to be used for these purposes. However, highly porous metallic material such as aluminium foam prepared by powder metallurgy [10, 11] is on the contrary excellently heat conductive, which predisposes it to be used for light-weight design of supporting structure of very energy efficient indoor as well as outdoor thermo-active heat exchangers for building industry of the future. This contribution points to the possibility to apply aluminium foam for both the novel innovative roofing system to cover pitched roofs and the interior ceiling panels, with the minimum energy demands for maintaining the sufficient thermal comfort in future nearly Zero-Energy Buildings (nZEBs).

Buildings ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 143 ◽  
Author(s):  
Juan Garcia ◽  
Lukas Kranzl

Since buildings account for 40% of total energy consumption and 36% of CO2 emissions in the European Union (EU), the directive 2010/31/EU “Energy Performance of Buildings Directive (EPDB)” among other legal provisions concerning the reduction of energy consumption of buildings has been enforced. According to this legislation, all new buildings must be nearly zero energy buildings “nZEB” by 31 December 2020 (public buildings by 31 December 2018). Nonetheless, the assessment of the “high energy performance” of a building is ambiguous and a cross country comparison seems to be intricate since different national building codes and nZEB definitions employ different energy indicators and methods. This paper delves into the question of how do the ambition levels of “nZEB” definitions and the transposition of the Directive 2010/31/EU into national law differ in four selected EU Countries: Austria, Germany, Spain, and England (as part of UK). The energy performance of some exemplary buildings is assessed by means of a simplified MATLAB model that is based on the norm DIN V-18599. The results drawn from this work show how diverse are building codes scopes and national “nZEB” definitions. Only 9 of the 36 studied cases of residential buildings obtain consistently the “nZEB” compliance status in all four selected countries. The results show that climate conditions, energy requirements, primary energy factors, ambition levels, and calculation methodologies lead to the problem of an uneven cross-country comparison. Moreover, primary energy consumption [kWh/m2a] set as the main quantitative energy indicator by the directive 2010/31/EU might not be the most suitable one for an EU level comparison.


2020 ◽  
pp. 1420326X2096115
Author(s):  
Jaime Resende ◽  
Marta Monzón-Chavarrías ◽  
Helena Corvacho

Buildings account for 34% of world energy consumption and about half of electricity consumption. The nearly/Net Zero Energy Building (nZEB/NZEB) concepts are regarded as solutions for minimizing this problem. The countries of Southern Europe, which included the nZEB concept recently in their regulatory requirements, have both heating and cooling needs, which adds complexity to the problem. Brazil may benefit from their experience since most of the Brazilian climate zones present significant similarities to the Southern European climate. Brazil recently presented a household energy consumption increase, and a growing trend in the use of air conditioning is predicted for the coming decades. Simulations with various wall and roof solutions following the Brazilian Performance Standard were carried out in a low standard single-family house in three different climate zones in order to evaluate thermal comfort conditions and energy needs. Results show that in milder climate zones, achieving thermal comfort with a low energy consumption is possible, and there is a great potential to achieve a net zero-energy balance. In the extreme hot climate zone, a high cooling energy consumption is needed to provide thermal comfort, and the implementation of a nearly zero-energy balance may be more feasible.


Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 6026
Author(s):  
Sergio Gómez Melgar ◽  
Antonio Sánchez Cordero ◽  
Marta Videras Rodríguez ◽  
José Manuel Andújar Márquez

The construction sector is a great contributor to global warming both in new and existing buildings. Minimum energy buildings (MEBs) demand as little energy as possible, with an optimized architectural design, which includes passive solutions. In addition, these buildings consume as low energy as possible introducing efficient facilities. Finally, they produce renewable energy on-site to become zero energy buildings (ZEBs) or even plus zero energy buildings (+ZEB). In this paper, a deep analysis of the energy use and renewable energy production of a social dwelling was carried out based on data measurements. Unfortunately, in residential buildings, most renewable energy production occurs at a different time than energy demand. Furthermore, energy storage batteries for these facilities are expensive and require significant maintenance. The present research proposes a strategy, which involves rescheduling energy demand by changing the habits of the occupants in terms of domestic hot water (DHW) consumption, cooking, and washing. Rescheduling these three electric circuits increases the usability of the renewable energy produced on-site, reducing the misused energy from 52.84% to 25.14%, as well as decreasing electricity costs by 58.46%.


2019 ◽  
Vol 40 (4) ◽  
pp. 470-491 ◽  
Author(s):  
Radwa Salem ◽  
Ali Bahadori-Jahromi ◽  
Anastasia Mylona

The death toll of the 2003 heat wave in Europe exceeded 35,000 heat-related deaths. The elderly population were the most affected. The current paradigm within the construction industry in cold-dominant countries is to design/retrofit buildings with high levels of insulation. Whilst thermal comfort may be reached during colder months with this approach, the risk of overheating can be increased during hotter months. This paper aims to examine the impacts of a changing climate on the risk of overheating and energy performance for a UK retirement village. For this study, the buildings within the retirement village will be designed to reach the nearly zero energy building standard. Consequently, the risk of overheating of the buildings within the retirement village as they currently stand and as zero energy buildings will be investigated under current and future climatic conditions. The analysis is carried out using thermal analysis simulation software (TAS, Edsl). Combined heat and power and combined cooling, heat and power will be investigated as mitigating strategies with regard to overheating. The results of this study do not undermine the importance of continuing to improve the energy efficiency of existing buildings but rather highlight that the approach undertaken should be reconsidered. Practical application: Currently, there is emphasis placed on retrofitting and designing buildings, with high energy efficiency standards. Whilst this is in line with our vision as a society towards reaching a decarbonised, sustainable future, this work highlights that doing so, carries risks with regard to overheating. Nonetheless, the results demonstrate that with the incorporation of suitable mitigation strategies and adequate ventilation strategies, it is possible to achieve an energy efficient building that meets the heating and cooling demand (and thereby thermal comfort of occupants) during the heating and non-heating season.


Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5524
Author(s):  
José Marco Lourenço ◽  
Laura Aelenei ◽  
Jorge Facão ◽  
Helder Gonçalves ◽  
Daniel Aelenei ◽  
...  

The 2018 revision of the European Performance Building Directive (EPBD) requires that from the year 2020 onwards, all new buildings will have to be “nearly zero energy buildings”. It also further promotes smart building technologies, raising awareness amongst building owners and occupants of the value behind building automation. The European Commission also identified, in 2011, Key Enabling Technologies (KETs), which provide the basis for innovation in the EU. In the frame of the SUDOKET project, the Solar XXI building was used as a pilot case, as innovative integrated solutions and technologies are monitored and controlled. The objective of this paper is to validate a simulation of the laboratorial test room in EnergyPlus with data obtained experimentally and determine the impact of the control systems on energy needs and on thermal comfort. Two systems, in particular, were studied: the Building-Integrated Photovoltaic (BIPV) and the earth tubes. Once validated, the simulation of the test room without the systems was created, allowing their impact to be determined. The results show that, for the analysed periods, BIPVs reduced the heating consumption by 22% while also increasing thermal comfort, and the earth tube system would reduce the cooling needs by 97%.


2016 ◽  
Vol 22 (4) ◽  
pp. 271 ◽  
Author(s):  
Jaroslav Jerz ◽  
František Simančík ◽  
Jaroslav Kováčik ◽  
Peter Oslanec Sr.

The high energy efficiency of buildings can be achieved if energy needs are almost entirely covered by the supply of renewable energy sources obtained directly on the building or in its immediate vicinity. The technology providing efficient storage of the heat at a time of excessive sunlight is necessary if a returns of investment for the construction of small houses with zero energy balance should be less than 10 years. The regular alternation of day and night cycle resulting in continuously changing amount of sunshine falling on the building roof causes even though a small but very well usable potential. The concept presented in this contribution is based on the storage of energy obtained through the aluminium foam roof and facade cladding, which are capable of absorbing the desired, or even take away the excess energy to the surroundings if necessary. The energy effectively generated by this way is by means of piping system distributed by heating liquid medium/coolant to interior ceiling heat exchangers made of aluminium foam enabling due to filling by <span style="text-decoration: underline;">P</span>hase <span style="text-decoration: underline;">C</span>hange <span style="text-decoration: underline;">M</span>aterial<span style="text-decoration: underline;">s</span> (PCMs) to store the energy required for heating/cooling for a period of at least several hours. This progressive technology, therefore, contributes significantly to reducing of energy demand and thus also the prices of future not only large buildings but also small family houses that are able to achieve the optimal thermal comfort by extremely low costs. Possibility to manufacture facade, as well as the interior panels of aluminium foam, is a good prerequisite for ensuring that these structural components could be in the nearest future made from fully recyclable aluminium alloys. This fact indicates large potential chance for long-term sustainable further development of above-mentioned advanced technologies.


2021 ◽  
Vol 13 (24) ◽  
pp. 13934
Author(s):  
Hanan S. S. Ibrahim ◽  
Ahmed Z. Khan ◽  
Yehya Serag ◽  
Shady Attia

Retrofitting “nearly-zero energy” heritage buildings has always been controversial, due to the usual association of the “nearly-zero energy” target with high energy performance and the utilization of renewable energy sources in highly regarded cultural values of heritage buildings. This paper aims to evaluate the potential of turning heritage building stock into a “nearly-zero energy” in hot, dry climates, which has been addressed in only a few studies. Therefore, a four-phase integrated energy retrofitting methodology was proposed and applied to a sample of heritage residential building stock in Egypt along with microscale analysis on buildings. Three reference buildings were selected, representing the most dominant building typologies. The study combines field measurements and observations with energy simulations. In addition, simulation models were created and calibrated based on monitored data in the reference buildings. The results show that the application of hybrid passive and active non-energy generating scenarios significantly impacts energy use in the reference buildings, e.g., where 66.4% of annual electricity use can be saved. Moreover, the application of solar energy sources approximately covers the energy demand in the reference buildings, e.g., where an annual self-consumption of electricity up to 78% and surplus electricity up to 20.4% can be achieved by using photo-voltaic modules. Furthermore, annual natural gas of up to 66.8% can be saved by using two unglazed solar collectors. Lastly, achieving “nearly-zero energy” was possible for the presented case study area. The originality of this work lies in developing and applying an informed retrofitting (nearly-zero energy) guide to be used as a benchmark energy model for buildings that belong to an important historical era. The findings contribute to fill a gap in existing studies of integrating renewable energy sources to achieve “nearly-zero energy” in heritage buildings in hot climates.


2019 ◽  
Vol 11 (24) ◽  
pp. 7032 ◽  
Author(s):  
Ji Li ◽  
Wei Xu ◽  
Ping Cui ◽  
Biao Qiao ◽  
Siyang Wu ◽  
...  

As a result of the impact of energy consumption, research on ultra-low energy, nearly zero-energy, and zero energy buildings has been conducted in China. However, the design of the nearly zero-energy building is flexible; the traditional architectural design method is not fully applicable to nearly zero-energy buildings. The paper proposed a performance-based design method based on overall energy consumption and progress for the nearly zero-energy building. The design process of the relevant cases was also analyzed. The factors of cold and heat sources, environment, and renewable energy were combined to make a comprehensive analysis to get the optimal scheme of the nearly zero-energy building in the case. In general, the performance-based design method has a certain guiding significance for the design of nearly zero-energy buildings and certainly promotes the expansion of the nearly zero-energy building industry in China.


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