scholarly journals Hybridization of Heat Pump Systems With Natural Ventilation To Improve Energy Efficiency in Cooling Dominated Buildings

2021 ◽  
Vol 6 ◽  
pp. 33
Author(s):  
Nuno R. Martins ◽  
Peter J. Bourne-Webb
Keyword(s):  
Heat Pump ◽  
Natural Ventilation ◽  
Energy Performance ◽  
Ground Temperature ◽  
Improve Energy Efficiency ◽  
Final Energy ◽  
Heating And Cooling ◽  
Energy Needs ◽  
Energy Simulations ◽  
Cooling Loads

Building foundation piles can be used as heat exchangers in ground-source heat pump (GSHP) systems to provide highly efficient renewable heating and cooling (H&C). Unbalanced H&C loads lead to heat build-up in the ground, decreasing the system's overall performance. In this study, the introduction of natural ventilation (NV) has been examined to decrease cooling load imbalance in cooling-dominated buildings to improve system efficiency. Building energy simulations estimated the H&C loads for an office building in three Portuguese cities: Lisbon, Porto and Faro, yielding heating loads of 0.2–3.6 MWh/year and cooling loads of 260–450 MWh/year. Four renewable H&C technology scenarios were used to assess energy performance: (1) an air-source heat pump (ASHP) system; (2) a GSHP system utilizing energy piles; (3) hybrid ASHP-NV and (4) hybrid GSHP-NV. Over 50 years of operation, in Scenario (1) COP values of 2.45–2.55 (heating) and 3.62–4.15 (cooling) were obtained. In (2), COP values increased to 4.15–4.34 (heating) but fell to 3.36–3.79 (cooling), which increased annual final energy needs by 7–8%. Unbalanced cooling loads increased the ground temperature by 21–24 °C, which is unlikely to be acceptable. Compared to (1), introducing NV reduced cooling loads by 65–90% in Scenarios (3) and (4), with the final energy needs decreasing by 59–80% and 62–88%, respectively. A further benefit of the GSHP-NV hybrid is that the ground temperature increase was limited to 8‑12 °C. For cooling, the COP in (3) decreased compared to (1) (3.14–3.69), while in (4), COP improved to 3.45–6.10. This study concludes that hybrid GSHP-NV systems should be considered in some cooling-dominated scenarios.

scholarly journals Assessment of the Impact of Occupants’ Behavior and Climate Change on Heating and Cooling Energy Needs of Buildings

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6468
Author(s):  
Gianmarco Fajilla ◽  
Marilena De Simone ◽  
Luisa F. Cabeza ◽  
Luís Bragança
Keyword(s):  
Climate Change ◽  
Natural Ventilation ◽  
Residential Buildings ◽  
Energy Performance ◽  
Future Scenarios ◽  
Occupant Behavior ◽  
Heating And Cooling ◽  
Energy Needs ◽  
Energy Simulations ◽  
The Impact

Energy performance of buildings is a worldwide increasing investigated field, due to ever more stringent energy standards aimed at reducing the buildings’ impact on the environment. The purpose of this paper is to assess the impact that occupant behavior and climate change have on the heating and cooling needs of residential buildings. With this aim, data of a questionnaire survey delivered in Southern Italy were used to obtain daily use profiles of natural ventilation, heating, and cooling, both in winter and in summer. Three climatic scenarios were investigated: The current scenario (2020), and two future scenarios (2050 and 2080). The CCWorldWeatherGen tool was used to create the weather files of future climate scenarios, and DesignBuilder was applied to conduct dynamic energy simulations. Firstly, the results obtained for 2020 demonstrated how the occupants’ preferences related to the use of natural ventilation, heating, and cooling systems (daily schedules and temperature setpoints) impact on energy needs. Heating energy needs appeared more affected by the heating schedules, while cooling energy needs were mostly influenced by both natural ventilation and usage schedules. Secondly, due to the temperature rise, substantial decrements of the energy needs for heating and increments of cooling energy needs were observed in all the future scenarios where in addition, the impact of occupant behavior appeared amplified.

The Performance Improvements of a Ground-Coupled Heat Pump System for both Building Heating and Cooling Modes

2011 ◽  
Vol 354-355 ◽  
pp. 807-810 ◽  
Author(s):  
Zi Shu Qi ◽  
Qing Gao ◽  
Yan Liu ◽  
Y.Y. Yan ◽  
Jeffrey D. Spitler
Keyword(s):  
Heat Pump ◽  
Temperature Response ◽  
Energy Performance ◽  
Coefficient Of Performance ◽  
Fluid Temperature ◽  
Time Step ◽  
Pump System ◽  
Heating And Cooling ◽  
Ground Coupled Heat Pump ◽  
Cooling Loads

The objective of the paper is to describe the performance of ground-coupled heat pump (GCHP) system in 20 years. A mathematical model for simulation of GCHP system is built based on long time-step Eskilson’s theory. The design methodology is based on a simulation that predicts the temperature response of the ground heat exchanger (GHE) to monthly heating and cooling loads and monthly peak heating and cooling demands over a number of years. The temperature response also has a secondary impact on the predicted energy consumption of the system, as the coefficient of performance (COP) of the heat pump varies with entering fluid temperature. This paper presents GCHP system can achieve better energy performance in building that heating and cooling loads are balanced all the year round. It is illustrated by performing a GHE for a 300 m2 building located in Changchun, China.

scholarly journals Full-scale operation of a novel two-pipe active beam system for simultaneous heating and cooling of office buildings

2019 ◽  
Vol 111 ◽  
pp. 01073
Author(s):  
Alessandro Maccarini ◽  
Göran Hultmark ◽  
Niels C. Bergsøe ◽  
Alireza Afshari
Keyword(s):  
Room Temperature ◽  
Energy Performance ◽  
Physical Parameters ◽  
Heating And Cooling ◽  
System A ◽  
A Value ◽  
Beam System ◽  
Simultaneous Heating ◽  
Simultaneous Heating And Cooling ◽  
Cooling Loads

This paper presents an investigation on the operation of a novel active beam system installed in an office building located in Jönköping, Sweden. The system consists of two parts: a dedicated outdoor air system (DOAS) to satisfy latent loads and ventilation requirements, and a water circuit to meet sensible heating and cooling loads. The novelty of the system is in relation to the water circuit, which is able to provide simultaneous heating and cooling through a single water loop that is near the room temperature. The energy performance of the system is currently being monitored through a number of sensors placed along the water circuit. Relevant physical parameters are being measured and data are available through a monitoring system. A preliminary analysis shows that the system is performing as designed. Results are shown for a typical week in winter, spring and summer. In particular, the supply water temperature in the circuit was between 20°C (in summer) and 23.2°C (in winter). The maximum supply/return temperature difference was found in summer and it assumed a value of 1.5 K. It is noticed that in spring supply and return water temperatures almost overlap.

scholarly journals Numerical Assessment of Zebra-Stripes-Based Strategies in Buildings Energy Performance: A Case Study under Tropical Climate

Biomimetics ◽  
2022 ◽  
Vol 7 (1) ◽  
pp. 14
Author(s):  
Miguel Chen Austin ◽  
Kevin Araque ◽  
Paola Palacios ◽  
Katherine Rodríguez Maure ◽  
Dafni Mora
Keyword(s):  
Energy Efficiency ◽  
Thermal Comfort ◽  
Natural Ventilation ◽  
Heat Dissipation ◽  
Energy Performance ◽  
Base Case ◽  
Energy Needs ◽  
Numerical Assessment ◽  
Lower Temperature

Urban growth has increased the risk of over-heating both in the microclimate and inside buildings, affecting thermal comfort and energy efficiency. That is why this research aims to evaluate the energy performance of buildings in terms of thermal comfort (operative temperature (OP) levels, satisfied hours of natural ventilation SHNV, thermal lag), and energy efficiency (roof heat gains and surface temperatures) in an urban area in Panama City, using superficial-heat-dissipation biomimetic strategies. Two case studies, a base case and a proposed case, were evaluated using the Designbuilder software through dynamic simulation. The proposed case is based on a combined biomimetic strategy; the reflective characteristics of the Saharan ant applied as a coating on the roofs through a segmented pattern such as the Zebra’s stripes (one section with coating, and another without). Results showed that the OP decreased from 8 to 10 °C for the entire urban zone throughout the year. A reduction of 3.13% corresponding to 8790 kWh per year was achieved for cooling energy consumption. A difference of 5 °C in external surface temperature was obtained, having a lower temperature in which the biomimetic strategy was applied. Besides, it was evidenced that a contrasted-reflectivity-stripes pitched roof performed better than a fully reflective roof. Thus, the functionality of Zebra stripes, together with the reflective characteristics of the Saharan ant, provide better performance for buildings’ thermal regulation and energy needs for cooling.

scholarly journals The application of the EN ISO 52016 standard and its Italian National Annex to assess the heating and cooling needs of a reference office building

2021 ◽  
Vol 312 ◽  
pp. 06003
Author(s):  
Franz Bianco Mauthe Degerfeld ◽  
Ilaria Ballarini ◽  
Giovanna De Luca ◽  
Vincenzo Corrado
Keyword(s):  
Building Energy ◽  
Energy Performance ◽  
Office Building ◽  
Dynamic Calculation ◽  
Building Stock ◽  
Existing Building ◽  
Building Energy Performance ◽  
Heating And Cooling ◽  
Energy Simulations

The EN ISO 52016-1 standard presents a new simplified dynamic calculation procedure, whose aim is to provide an accurate energy performance assessment without excessively increasing the number of data required. The Italian National Annex to EN ISO 52016-1, currently under development, provides some improvements to the hourly calculation method; despite many works can be found in literature on the hourly model of EN ISO 52016-1, the National Annexes application has not been sufficiently analysed yet. The aim of the present work is to assess the main improvements introduced by the Italian National Annex and to compare the main results, in terms of energy need for space heating and cooling. To this purpose, an existing building representative of the Italian office building stock in Northern Italy was selected as a case study. The energy simulations were carried out considering both continuous and reduced operation of the HVAC systems. The options specified in the Italian National Annex were firstly applied one by one, and then all together. The variation of the energy need compared to the international base procedure is finally quantified. For the premises and the scope above discussed, the present work is intended to enhance the standardisation activity towards the adoption of more accurate and trustable calculation methods of the building energy performance.

Designing a mediator space and the study of its effect on the energy consumption of a residential building using EnergyPlus software in Savadkuh, Iran

2019 ◽  
Vol 17 (4) ◽  
pp. 833-846
Author(s):  
Yasaman Yousefi ◽  
Mehdi Jahangiri ◽  
Akbar Alidadi Shamsabadi ◽  
Afshin Raeesi Dehkordi
Keyword(s):  
Energy Consumption ◽  
Design Methodology ◽  
Residential Building ◽  
Environmental Costs ◽  
Content Type ◽  
Design And Implementation ◽  
Heating And Cooling ◽  
Energy Simulations ◽  
Cooling Loads ◽  
Reducing Energy

Purpose Reducing energy consumption of a building may have a significant effect on the energy and environmental costs. Nowadays, energy simulations have come to the aid of engineers in the design and implementation of buildings with a perspective on energy consumption. Design/methodology/approach In the current study, the suggested volume of a residential building in the Savadkuh City, Iran, is modeled using Ecotect® software, and the amount of radiation on the sides during various months of the year is studied. Then, using EnergyPlus™ software, climate analyses are performed on the suggested design, and finally, the amount of heating and cooling loads of the building are examined under two difference scenarios of mediator space. Findings Results indicated that nearly at all times of the year, both the heating and cooling loads were reduced in the scenario where mediator space had two functions, i.e. as greenhouse and as a space for higher ventilation, compared to the scenario where mediator space did not have a climate role and merely served as an entrance and passageway with rigid dividers. Originality/value Nowadays, energy simulations have come to the aid of engineers in the design and implementation of buildings with a perspective on energy consumption. Therefore, in the current study, the suggested volume of a residential building in the Savadkuh City, Iran, is modeled using Ecotect® software, and the amount of radiation on the sides during various months of the year is studied. Then, using EnergyPlus™ software, climate analyses are performed on the suggested design, and finally, the amount of heating and cooling loads of the building are examined under two difference scenarios of mediator space.

Analysis of Building Envelope Performance Effects of an Insulating Semi-Transparent Photovoltaic (STPV) Glazing Unit

2014 ◽  
Author(s):  
Dirk V. P. McLaughlin ◽  
Konstantinos Kapsis ◽  
Andreas K. Athienitis ◽  
Sam Siassi ◽  
Livio Nichilo
Keyword(s):  
Performance Standards ◽  
Energy Performance ◽  
Building Envelope ◽  
Commercial Building ◽  
Heating And Cooling ◽  
Performance Effects ◽  
Gas Consumption ◽  
U Value ◽  
And Performance ◽  
Cooling Loads

This paper presents characterization results for the electrical and thermal properties of a unique insulating semi-transparent photovoltaic (STPV) glazing unit using calorimetry hot box methods finding a U-value of 1.09 W/m2·°C and a SHGC of 0.11. These properties are then applied to an energy model of a case study commercial building in a continental climate region to examine the effects of utilizing STPV in the building envelope on the electricity and natural gas consumption levels and peak demands. The results indicate that such a building envelope can significantly reduce heating and cooling loads compared to standard glazing which would help architects maintain the desirable properties of highly glazed façades while avoiding the drop in building energy performance that could make adhering to increasingly stringent building codes and performance standards difficult. The paper also presents simulation results for the photovoltaic energy generation of the vertical STPV façades at two building orientations.

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