Building Energy Performances of Pre/Post TAB Practices for Heat Recovery Ventilation Systems in Residential Buildings and its On-site Surveys

Decentralized regenerative mechanical ventilation systems have acquired relevance in recent years for the retrofit of residential buildings. While manufacturers report heat recovery efficiencies over 90%, research has shown that the efficiencies often vary between 60% and 80%. In order to better understand this mismatch, a test facility is designed and constructed for the experimental characterization and validation of regenerative heat exchanger simulation models. A ceramic honeycomb heat exchanger, typical for decentralized regenerative ventilation devices, is measured in this test facility. The experimental data are used to validate two modeling approaches: a one-dimensional model in Modelica and a computational fluid dynamics (CFD) model built in COMSOL Multiphysics®. The results show an overall acceptable thermal performance of both models, the 1D model having a much lower simulation time and, thus, being suitable for integration in building performance simulations. A test case is designed, where the importance of an appropriate thermal and hydraulic modeling of decentralized ventilation systems is investigated. Therefore, the device is integrated into a multizone building simulation case. The results show that including component-based heat recovery and fan modeling leads to 30% higher heat losses due to ventilation and 10% more fan energy consumption than when assuming constant air exchange rates with ideal heat recovery. These findings contribute to a better understanding of the behavior of a growing technology such as decentralized ventilation and confirm the need for further research on these systems.

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Review of Heat Recovery Technologies for Building Applications

Energies ◽

10.3390/en12071285 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1285 ◽

Cited By ~ 6

Author(s):

Qi Xu ◽

Saffa Riffat ◽

Shihao Zhang

Keyword(s):

Heat Recovery ◽

High Performance ◽

Natural Ventilation ◽

Residential Buildings ◽

Global Climate ◽

Real Life ◽

Thermal Conductance ◽

Thermoelectric Module ◽

Residential Building ◽

Ventilation Systems

In recent years, interest in heat recovery systems for building applications has resurged due to concerns about the energy crisis and global climate changes. This review presents current developments in four kinds of heat recovery systems for residential building applications. A extensive investigation into the heat recovery integrated in energy-saving systems of residential buildings is also covered, including passive systems for building components, mechanical/natural ventilation systems, dehumidification systems, and the thermoelectric module (TE) system. Based on this review, key issues have been identified as follows: (1) The combination of heat recovery and energy-efficient systems could be considered as a promising approach to reduce greenhouse gas emissions and make residential buildings meet high performance and comfort requirements. However, real-life evaluation of these systems with economic analysis is insufficient; (2) When heat recovery is applied to mechanical ventilation systems, issues such as pressure leakages and air shortcuts should be addressed; (3) The heat pipe heat recovery system enjoys more potential in being combined with other sustainable technologies such as thermoelectric modules and solar energy systems due to its advantages, which include handy manufacturing and convenient maintenance, a lack of cross contamination, and greater thermal conductance.

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Decentralized Ventilation Systems with Exhaust Air Heat Recovery in the Case of Residential Buildings

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.680.524 ◽

2014 ◽

Vol 680 ◽

pp. 524-528 ◽

Cited By ~ 14

Author(s):

Vera Murgul ◽

Dusan Vuksanovic ◽

Nikolay Vatin ◽

Viktor Pukhkal

Keyword(s):

Heat Recovery ◽

Residential Buildings ◽

Basic System ◽

Ventilation Systems

Decentralized ventilation systems applied in residential buildings are generalized in this article. Basic system elements and devices and tools assigned for its application are considered herein. Basic requirements for design of the ventilation systems used in residential buildings are stipulated.

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Application Method of a Simplified Heat and Moisture Transfer Model of Building Construction in Residential Buildings

Energies ◽

10.3390/en14144180 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4180

Author(s):

Joowook Kim ◽

Michael Brandemuehl

Keyword(s):

Latent Heat ◽

Moisture Transfer ◽

Residential Buildings ◽

Building Energy ◽

The United States ◽

Building Envelope ◽

Outdoor Environment ◽

Transfer Model ◽

Heat And Moisture Transfer ◽

Heat And Moisture

Several building energy simulation programs have been developed to evaluate the indoor conditions and energy performance of buildings. As a fundamental component of heating, ventilating, and air conditioning loads, each building energy modeling tool calculates the heat and moisture exchange among the outdoor environment, building envelope, and indoor environments. This paper presents a simplified heat and moisture transfer model of the building envelope, and case studies for building performance obtained by different heat and moisture transfer models are conducted to investigate the contribution of the proposed steady-state moisture flux (SSMF) method. For the analysis, three representative humid locations in the United States are considered: Miami, Atlanta, and Chicago. The results show that the SSMF model effectively complements the latent heat transfer calculation in conduction transfer function (CTF) and effective moisture penetration depth (EMPD) models during the cooling season. In addition, it is found that the ceiling part of a building largely constitutes the latent heat generated by the SSMF model.

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Evaluation of Urban-Scale Building Energy-Use Models and Tools—Application for the City of Fribourg, Switzerland

Sustainability ◽

10.3390/su13041595 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1595

Author(s):

Valeria Todeschi ◽

Roberto Boghetti ◽

Jérôme H. Kämpf ◽

Guglielmina Mutani

Keyword(s):

Machine Learning ◽

Energy Use ◽

Residential Buildings ◽

Building Energy ◽

Energy Performance ◽

Space Heating ◽

Engineering Model ◽

Building Energy Use ◽

The Impact ◽

The City

Building energy-use models and tools can simulate and represent the distribution of energy consumption of buildings located in an urban area. The aim of these models is to simulate the energy performance of buildings at multiple temporal and spatial scales, taking into account both the building shape and the surrounding urban context. This paper investigates existing models by simulating the hourly space heating consumption of residential buildings in an urban environment. Existing bottom-up urban-energy models were applied to the city of Fribourg in order to evaluate the accuracy and flexibility of energy simulations. Two common energy-use models—a machine learning model and a GIS-based engineering model—were compared and evaluated against anonymized monitoring data. The study shows that the simulations were quite precise with an annual mean absolute percentage error of 12.8 and 19.3% for the machine learning and the GIS-based engineering model, respectively, on residential buildings built in different periods of construction. Moreover, a sensitivity analysis using the Morris method was carried out on the GIS-based engineering model in order to assess the impact of input variables on space heating consumption and to identify possible optimization opportunities of the existing model.

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Proposing Alternative Solutions to Enhance Natural Ventilation Rates in Residential Buildings in the Cfa Climate Zone of Rasht

Sustainability ◽

10.3390/su13020679 ◽

2021 ◽

Vol 13 (2) ◽

pp. 679

Author(s):

Roya Aeinehvand ◽

Amiraslan Darvish ◽

Abdollah Baghaei Daemei ◽

Shima Barati ◽

Asma Jamali ◽

...

Keyword(s):

Natural Ventilation ◽

Residential Buildings ◽

Residential Building ◽

Ventilation Rate ◽

Humid Climate ◽

The Sustainable Development ◽

Passive Strategies ◽

Development Goals ◽

Ventilation Rates ◽

Ventilation Systems

Today, renewable resources and the crucial role of passive strategies in energy efficiency in the building sector toward the sustainable development goals are more indispensable than ever. Natural ventilation has traditionally been considered as one of the most fundamental techniques to decrease energy usage by building dwellers and designers. The main purpose of the present study is to enhance the natural ventilation rates in an existing six-story residential building situated in the humid climate of Rasht during the summertime. On this basis, two types of ventilation systems, the Double-Skin Facade Twin Face System (DSF-TFS) and Single-Sided Wind Tower (SSWT), were simulated through DesignBuilder version 4.5. Then, two types of additional ventilation systems were proposed in order to accelerate the airflow, including four-sided as well as multi-opening wind towers. The wind foldable directions were at about 45 degrees (northwest to southeast). The simulation results show that SSWT could have a better performance than the aforementioned systems by about 38%. Therefore, the multi-opening system was able to enhance the ventilation rate by approximately 10% during the summertime.

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Decarbonization of Residential Building Energy Supply: Impact of Cogeneration System Performance on Energy, Environment, and Economics

Energies ◽

10.3390/en14092538 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2538

Author(s):

Praveen K. Cheekatamarla

Keyword(s):

Carbon Dioxide ◽

Power Generation ◽

Energy Consumption ◽

Carbon Footprint ◽

Residential Buildings ◽

Building Energy ◽

Primary Energy ◽

Primary Energy Consumption ◽

Cogeneration System ◽

The Impact

Electrical and thermal loads of residential buildings present a unique opportunity for onsite power generation, and concomitant thermal energy generation, storage, and utilization, to decrease primary energy consumption and carbon dioxide intensity. This approach also improves resiliency and ability to address peak load burden effectively. Demand response programs and grid-interactive buildings are also essential to meet the energy needs of the 21st century while addressing climate impact. Given the significance of the scale of building energy consumption, this study investigates how cogeneration systems influence the primary energy consumption and carbon footprint in residential buildings. The impact of onsite power generation capacity, its electrical and thermal efficiency, and its cost, on total primary energy consumption, equivalent carbon dioxide emissions, operating expenditure, and, most importantly, thermal and electrical energy balance, is presented. The conditions at which a cogeneration approach loses its advantage as an energy efficient residential resource are identified as a function of electrical grid’s carbon footprint and primary energy efficiency. Compared to a heat pump heating system with a coefficient of performance (COP) of three, a 0.5 kW cogeneration system with 40% electrical efficiency is shown to lose its environmental benefit if the electrical grid’s carbon dioxide intensity falls below 0.4 kg CO2 per kWh electricity.

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Modifying Building Energy-Saving Design Based on Field Research into Climate Features and Local Residents’ Habits

Energies ◽

10.3390/en14020442 ◽

2021 ◽

Vol 14 (2) ◽

pp. 442

Author(s):

Xiaoyue Zhu ◽

Bo Gao ◽

Xudong Yang ◽

Zhong Yu ◽

Ji Ni

Keyword(s):

Energy Consumption ◽

Energy Saving ◽

Residential Buildings ◽

Average Energy ◽

Field Tests ◽

Building Energy ◽

Building Energy Efficiency ◽

Local Conditions ◽

Building Energy Saving ◽

Average Energy Consumption

In China, a surging urbanization highlights the significance of building energy conservation. However, most building energy-saving schemes are designed solely in compliance with prescriptive codes and lack consideration of the local situations, resulting in an unsatisfactory effect and a waste of funds. Moreover, the actual effect of the design has yet to be thoroughly verified through field tests. In this study, a method of modifying conventional building energy-saving design based on research into the local climate and residents’ living habits was proposed, and residential buildings in Panzhihua, China were selected for trial. Further, the modification scheme was implemented in an actual project with its effect verified by field tests. Research grasps the precise climate features of Panzhihua, which was previously not provided, and concludes that Panzhihua is a hot summer and warm winter zone. Accordingly, the original internal insulation was canceled, and the shading performance of the windows was strengthened instead. Test results suggest that the consequent change of SET* does not exceed 0.5 °C, whereas variations in the energy consumption depend on the room orientation. For rooms receiving less solar radiation, the average energy consumption increased by approximately 20%, whereas for rooms with a severe western exposure, the average energy consumption decreased by approximately 11%. On the other hand, the cost savings of removing the insulation layer are estimated at 177 million RMB (1 USD ≈ 6.5 RMB) per year. In conclusion, the research-based modification method proposed in this study can be an effective tool for improving building energy efficiency adapted to local conditions.

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A Rapid Review on Community Connected Microgrids

Sustainability ◽

10.3390/su13126753 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6753

Author(s):

Moiz Masood Syed ◽

Gregory M. Morrison

Keyword(s):

Literature Review ◽

Urban Areas ◽

Energy Use ◽

Residential Buildings ◽

Optimal Solution ◽

Building Energy ◽

Rapid Review ◽

Solar Pv ◽

Electricity Cost ◽

Building Energy Use

As the population of urban areas continues to grow, and construction of multi-unit developments surges in response, building energy use demand has increased accordingly and solutions are needed to offset electricity used from the grid. Renewable energy systems in the form of microgrids, and grid-connected solar PV-storage are considered primary solutions for powering residential developments. The primary objectives for commissioning such systems include significant electricity cost reductions and carbon emissions abatement. Despite the proliferation of renewables, the uptake of solar and battery storage systems in communities and multi-residential buildings are less researched in the literature, and many uncertainties remain in terms of providing an optimal solution. This literature review uses the rapid review technique, an industry and societal issue-based version of the systematic literature review, to identify the case for microgrids for multi-residential buildings and communities. The study describes the rapid review methodology in detail and discusses and examines the configurations and methodologies for microgrids.

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