Impact of building design parameters precision on heating and cooling load calculations

To improve the energy efficiency of dwellings, rooftop photovoltaic (PV) technology is proposed in contemporary designs; however, adopting this technology will add a new component to the roof that may affect its thermal balance. This paper studies the effect of roof shading developed by solar PV panels on dwellings’ thermal performance. The analysis in this work is performed by using two types of software packages: “AccuRate Sustainability” for rating the energy efficiency of a residential building design, and “PVSYST” for the solar PV power system design. AccuRate Sustainability is used to calculate the annual heating and cooling load, and PVSYST is used to evaluate the power production from the rooftop PV system. The analysis correlates the electrical energy generated from the PV panels to the change in the heating and cooling load due to roof shading. Different roof orientations, roof inclinations, and roof insulation, as well as PV dwelling floor areas, are considered in this study. The analysis shows that the drop in energy efficiency due to the shaded area of the roof by PV panels is very small compared to the energy generated by these panels. The analysis also shows that, with an increasing number of floors in the dwelling, the effect of shading by PV panels on thermal performance becomes negligible. The results show that insensitivity of the annual heating and cooling load to the thermal resistance of rooftop solar systems is only because the total thermal resistance is dominated by roof insulation.

Download Full-text

Comparison of Factorial and Latin Hypercube Sampling Designs for Meta-Models of Building Heating and Cooling Loads

Energies ◽

10.3390/en14020512 ◽

2021 ◽

Vol 14 (2) ◽

pp. 512

Author(s):

Younhee Choi ◽

Doosam Song ◽

Sungmin Yoon ◽

Junemo Koo

Keyword(s):

Latin Hypercube Sampling ◽

Building Design ◽

Gain Coefficient ◽

Design Parameters ◽

Latin Hypercube ◽

Heating And Cooling ◽

Factor Design ◽

Heating Loads ◽

Cooling Loads ◽

Interest In Research

Interest in research analyzing and predicting energy loads and consumption in the early stages of building design using meta-models has constantly increased in recent years. Generally, it requires many simulated or measured results to build meta-models, which significantly affects their accuracy. In this study, Latin Hypercube Sampling (LHS) is proposed as an alternative to Fractional Factor Design (FFD), since it can improve the accuracy while including the nonlinear effect of design parameters with a smaller size of data. Building energy loads of an office floor with ten design parameters were selected as the meta-models’ objectives, and were developed using the two sampling methods. The accuracy of predicting the heating/cooling loads of the meta-models for alternative floor designs was compared. For the considered ranges of design parameters, window insulation (WDI) and Solar Heat Gain Coefficient (SHGC) were found to have nonlinear characteristics on cooling and heating loads. LHS showed better prediction accuracy compared to FFD, since LHS considers the nonlinear impacts for a given number of treatments. It is always a good idea to use LHS over FFD for a given number of treatments, since the existence of nonlinearity in the relation is not pre-existing information.

Download Full-text

A novel method based on extreme learning machine to predict heating and cooling load through design and structural attributes

Energy and Buildings ◽

10.1016/j.enbuild.2018.06.056 ◽

2018 ◽

Vol 176 ◽

pp. 275-286 ◽

Cited By ~ 14

Author(s):

Sachin Kumar ◽

Saibal K. Pal ◽

Ram Pal Singh

Keyword(s):

Extreme Learning Machine ◽

Cooling Load ◽

Heating And Cooling ◽

Novel Method ◽

Learning Machine ◽

Heating And Cooling Load

Download Full-text

The Effects of Window Film on the Performance of Window System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.525.408 ◽

2014 ◽

Vol 525 ◽

pp. 408-411

Author(s):

Min Seon Jang ◽

Gyeong Seok Choi ◽

Jae Sik Kang ◽

Yumin Kim

Keyword(s):

Energy Consumption ◽

Cooling Load ◽

Indoor Temperature ◽

Heating And Cooling ◽

Window System ◽

Window Systems ◽

Clear Glass ◽

Window Film ◽

And Performance ◽

Heating And Cooling Load

Window film is generally attached the glazing in buildings to improve the thermal performance of the window system by addressing a range of problems such as indoor temperature rise, indoor temperature imbalance, degraded heating and cooling load due to excessive influx of solar radiation. To evaluate the performance of window films, window films are attached to 3mm or 6mm clear glass. However, window films are generally used on existing window systems for reducing the annual energy consumption. Therefore it is necessary to evaluate the performance of window films depending on the performance of glazing such as clear double glazing or low-e double glazing. Thus the purpose of this study is to analyze the performance of window systems when window film is attached. As a result, in the case of applying window films for reducing the SHGC of buildings, it is necessary to select window films suitable for the configuration and performance of the glazing to be installed, considering the SHGC of the entire glazing system.

Download Full-text