Submit to Energies Review for Energies Propose a Special Issue

Journal Menu

Journal Browser

► Journal Browser

Energy Performance and Indoor Climate in Buildings

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Benefits of Publishing in a Special Issue
Published Papers

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "G: Energy and Buildings".

Deadline for manuscript submissions: closed (31 December 2020) | Viewed by 34847

Share This Special Issue

Special Issue Editors

Prof. Dr. Jarek Kurnitski

E-Mail Website
Guest Editor

Department of Civil Engineering and Architecture, Tallinn University of Technology, 19086 Tallinn, Estonia
Interests: energy performance; indoor climate; zero energy buildings; HVAC systems; building simulation
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Martin Thalfeldt

E-Mail Website
Guest Editor

Department of Civil Engineering and Architecture, Tallinn University of Technology, 19086 Tallinn, Estonia
Interests: building physics and energy efficiency
Special Issues, Collections and Topics in MDPI journals

Dr. Andrea Ferrantelli

E-Mail Website
Guest Editor

1. Department of Civil Engineering, Aalto University, Espoo, Finland
2. Department of Mechanical Engineering, Aalto University, Espoo, Finland
3. Department of Civil Engineering and Architecture, Tallinn University of Technology, Tallinn, Estonia
Interests: heat transfer; theoretical modeling; building simulation; energy performance; thermal comfort; indoor air quality; statistical analysis; energy benchmarking
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

This Special Issue is dedicated to energy performance, HVAC, and other technical systems, and indoor climate analyses in buildings. Articles dealing both with new and renovated, low energy and nearly zero energy buildings (NZEB) are welcomed. On the background of this issue are NZEB requirements recently established and taken into use from 2020 in most EU Member States, as well as similar developments in Japan, the US, and other countries. NZEB definitions, system boundaries, performance levels, and energy calculation input data show no consensus on the European level, indicating a need for benchmarking for future harmonization in the common market. Long-term renovation strategies aiming to transform all existing building stock to nearly zero energy performance level of major renovation by 2050 bring similar questions and technical and financial challenges to the renovation market. Therefore, it is difficult to understand which countries have set stringent requirement leading to the best possible energy performance. Climate differences provide an additional challenge, and a common energy performance scale is not yet available. Revised EPBD directive stresses that the specification of adequate ventilation and comfort levels is the responsibility of Member States, which calls for comparative analyses on how indoor environmental quality (IEQ) criteria are set nationally and how a good IEQ is achieved in practice in new or in deeply renovated highly-performing buildings. Benchmarking, assessment of technical solutions needed for NZEB, performance analyses of HVAC systems, cost optimality, and energy flexibility measures in the context of new smart readiness indicators are some examples of topics which are highly welcome in this Special Issue.

Prof. Dr. Jarek Kurnitski
Prof. Dr. Martin Thalfeldt
Dr. Andrea Ferrantelli
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

energy performance
HVAC systems
indoor climate
nearly zero energy buildings
major renovation
long-term renovation strategy

Benefits of Publishing in a Special Issue

Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (11 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Research

22 pages, 13696 KiB

Open AccessArticle

Selected Aspects of Indoor Climate in a Passive Office Building with a Thermally Activated Building System: A Case Study from Poland

by Piotr Michalak

Energies 2021, 14(4), 860; https://doi.org/10.3390/en14040860 - 7 Feb 2021

Cited by 23 | Viewed by 3652

Abstract

Modern buildings with new heating, ventilation and air conditioning (HVAC) systems offer possibility to fit parameters of the indoor environment to the occupants’ requirements. The present paper describes the results of measurements performed in an office room in the first Polish passive commercial office building during four months of normal operation. They were used to calculate parameters describing thermal comfort: vertical air temperature profile, floor surface temperature, predicted mean vote (PMV) and predicted percent of dissatisfied (PPD). Obtained results confirmed good thermal conditions in the analysed room. The average temperature of the floor’s surface varied from 20.6 °C to 26.2 °C. The average vertical air temperature, calculated for working days, was from 22.5 °C to 23.1 °C. The temperature difference between the floor and 5 cm below the ceiling was from −0.9 °C to 6.3 °C. The PMV index varied from 0.52 to 1.50 indicating ‘slightly warm’ sensation, in spite of ‘neutral’ reported by employees. Also measured cooling and heating energy consumption was presented. The performed measurements confirmed the ability of thermally activated building system (TABS) to keep good thermal conditions. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Graphical abstract

20 pages, 4844 KiB

Open AccessArticle

New Equation for Optimal Insulation Dependency on the Climate for Office Buildings

by Kaiser Ahmed and Jarek Kurnitski

Energies 2021, 14(2), 321; https://doi.org/10.3390/en14020321 - 8 Jan 2021

Cited by 3 | Viewed by 2169

Abstract

The comparison of building energy efficiency in different climates is a growing issue. Unique structural solutions will not ensure the same energy use, but the differences also remain if cost-optimal solutions are applied. This study developed a new equation for the assessment of building envelope optimal insulation in different climates for office buildings. The developed method suggests determining actual degree days from simulated heating energy need and the thermal conductance of a building, avoiding in such a way the use of a base temperature. The method was tested in four climates and validated against cost-optimal solutions solved with optimization. The accuracy of the method was assessed with sensitivity analyses of key parameters such as window-to-wall ratios (WWRs), window g-values, costs of heating, and electricity. These results showed that the existing square root equation overestimated the climate difference effect so that the calculation from the cold climate U-value resulted in less insulation than cost-optimal in warmer climates. Parametric analyses revealed that the power value of 0.2 remarkably improved the accuracy as well as performance worked well in all cases and can be recommended as a default value. Sensitivity analyses with a broad range of energy costs and window parameters revealed that the developed equation resulted in maximum 5% underestimation and maximum 7% overestimation of an average area-weighted optimal U-value of building envelope in another climate. The developed method allows objectively to compare optimal insulation of the building envelope in different climates. The method is easy to apply for energy performance comparison of similar buildings in different climates and also for energy performance requirements comparison. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

19 pages, 2089 KiB

Open AccessArticle

A Supervisory Control Strategy for Improving Energy Efficiency of Artificial Lighting Systems in Greenhouses

by Gianluca Serale, Luca Gnoli, Emanuele Giraudo and Enrico Fabrizio

Energies 2021, 14(1), 202; https://doi.org/10.3390/en14010202 - 2 Jan 2021

Cited by 11 | Viewed by 2737

Abstract

Artificial lighting systems are used in commercial greenhouses to ensure year-round yields. Current Light Emitting Diode (LED) technologies improved the system efficiency. Nevertheless, having artificial lighting systems extended for hectares with power densities over

50 W / m^{2}

causes energy and power [...] Read more.

50 W / m^{2}

causes energy and power demand of greenhouses to be really significant. The present paper introduces an innovative supervisory and predictive control strategy to optimize the energy performance of the artificial lights of greenhouses. The controller has been implemented in a multi-span plastic greenhouse located in North Italy. The proposed control strategy has been tested on a greenhouse of 1 hectare with a lighting system with a nominal power density of 50

W

m^{- 2}

requiring an overall power supply of 1

M

W

for a period of 80 days. The results have been compared with the data coming from another greenhouse of 1 hectare in the same conditions implementing a state-of-the-art strategy for artificial lighting control. Results outlines that potential 19.4% cost savings are achievable. Moreover, the algorithm can be used to transform the greenhouse in a viable source of energy flexibility for grid reliability. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

21 pages, 3486 KiB

Open AccessArticle

The Applicability of Coanda Effect Hysteresis for Designing Unsteady Ventilation Systems

by Aldona Skotnicka-Siepsiak

Energies 2021, 14(1), 34; https://doi.org/10.3390/en14010034 - 23 Dec 2020

Cited by 6 | Viewed by 2648

Abstract

Energy-saving ventilation systems are designed to improve the energy efficiency of buildings. Low energy efficiency in buildings poses a considerable problem that needs to be addressed. Mechanical ventilation with heat recovery has gained increased popularity in recent years. Mechanical ventilation has numerous advantages, including easy adjustment and control, high indoor air quality and elimination of indoor pollutants. Mixing ventilation is the most popular type of mechanical ventilation, in particular in residential buildings. Unsteady ventilation is a type of mixing ventilation that involves stronger mixing effects and smaller vertical temperature gradients to improve indoor air quality (IAQ) and minimize energy consumption. This study examines the possibility of controlling and modifying Coanda effect hysteresis (CEH) to generate unsteady flow and simulate the conditions of unsteady mixing ventilation. The experiment was performed on a self-designed test bench at the University of Warmia and Mazury in Olsztyn. It demonstrated that an auxiliary nozzle can be applied at the diffuser outlet to control CEH and the angles at which the air jet becomes attached to and separated from the flat plate positioned directly behind the nozzle. The study proposes an innovative mixing ventilation system that relies on CEH. The potential of the discussed concept has not been recognized or deployed in practice to date. This is the first study to confirm that an auxiliary nozzle by the diffuser outlet can be operated in both injection and suction mode to control CEH. In the future, the results can be used to design a new type of nozzles for unsteady ventilation systems that are based on CEH control. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

17 pages, 3918 KiB

Open AccessArticle

Development of a Reduced Order Model of Solar Heat Gains Prediction

by Meril Tamm, Jordi Macià Cid, Roser Capdevila Paramio, Joan Farnós Baulenas, Martin Thalfeldt and Jarek Kurnitski

Energies 2020, 13(23), 6316; https://doi.org/10.3390/en13236316 - 30 Nov 2020

Cited by 5 | Viewed by 2102

Abstract

The aim of this study was to elaborate and validate a reduced order model able to forecast solar heat gains as a function of the architectural parameters that determine the solar heat gains. The study focused on office buildings in Catalonia and Spain and their physical values were taken from the Spanish Building Technical Code and European Union Directive 2018/844. A reduced order model with three direct variables (solar heat gain coefficient, shade factor, window to wall ratio) and one indirect design variable (building orientation) was obtained and validated in respect to the International Performance Measurement and Verification Protocol. Building envelope properties were fixed and the values were taken from the national standards of Spain. This work validates solar heat gain coefficient as a primary variable in determining the annual solar heat gains in a building. Further work of developed model could result in building energy need quick evaluation tool in terms of solar heat gains for architects in building early stage as it has an advantage over detailed building simulation programs in terms of instant calculation and the limited need for predefined input data. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

14 pages, 2807 KiB

Open AccessArticle

The Effect of CO₂ Concentration on Children’s Well-Being during the Process of Learning

by Snezana Bogdanovica, Jurgis Zemitis and Raimonds Bogdanovics

Energies 2020, 13(22), 6099; https://doi.org/10.3390/en13226099 - 21 Nov 2020

Cited by 26 | Viewed by 5458

Abstract

There are more than 200 thousand pupils in Latvia. Most of them are still learning in non-renovated classrooms without proper mechanical ventilation. The classrooms are often ventilated only during the breaks by opening windows. This can lead to increased CO₂ levels and reduced mental performance. To test how CO₂ concentration in classrooms influences student attention level and their ability to perform mental tasks, the students had to complete a short test at the start and the end of the class. At the same time CO₂ concentration, temperature and relative humidity were logged. In addition, an anonymous survey on how the pupils felt regarding the overall indoor environmental quality (IEQ) in the classroom, their thermal sensation, are they fatigued, any difficulty concentrating and if they have headaches during the lesson performed. The measurements were performed in a Secondary School in Daugavpils, Latvia. The analysis of results shows that existing 10 min breaks are not enough to fully ventilate the classroom, and they must be increased to at least 15 min. At the same time, 30 min breaks can be reduced to 20 min. The correlation between CO₂ concentration and test results of pupils’ performance test results is noticeable but not definitive. It indicates that at increased CO₂ levels the performance lowers—when the concentration of CO₂ corresponds only to the Category 3 norm, the lowest results are achieved while the best results are when the CO₂ concentration level corresponds to Category 1. To improve the study, observations of CO₂ concentrations must be extended throughout the school year, as well as measurements in other classrooms in the school should be made. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

16 pages, 633 KiB

Open AccessArticle

Adoption of Energy Efficiency Measures in Renovation of Single-Family Houses: A Comparative Approach

by Shoaib Azizi, Gireesh Nair and Thomas Olofsson

Energies 2020, 13(22), 6042; https://doi.org/10.3390/en13226042 - 19 Nov 2020

Cited by 10 | Viewed by 2390

Abstract

Inclusion of energy efficiency measures (EEMs) in the renovation of the single-family housing stock can unlock the potential for much-needed energy efficiency to tackle climate change. Energy renovation (ER) in single-family houses is often promoted as an aggregate process, and EEMs are treated homogenously without sufficient attention to their differences. This study applies a comparative analysis on common EEMs using chi-square test to investigate the influence of factors already found affecting the implementation of ER. This paper addresses the “personal” and “house-related” factors influencing the adoption of EEMs regardless of motives or barriers leading the adopters’ decisions. This strategy is useful to highlight the contexts leading to an increase in the adoption rate of different EEMs. The analysis is based on a questionnaire survey mailed in spring 2017 to 1550 single-family homeowners in the northern region of Sweden. Approximately 60% of respondents showed interest in adopting at least one EEM if they implement a major renovation. About 46% of respondents stated to have at least one indoor environmental problem (IEP) in their houses, and IEPs are found to have significant relations with homeowners’ interest to adopt several different EEMs. The policy implications related to different EEMs are discussed. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

19 pages, 8954 KiB

Open AccessArticle

Office Building Tenants’ Electricity Use Model for Building Performance Simulations

by Andrea Ferrantelli, Helena Kuivjõgi, Jarek Kurnitski and Martin Thalfeldt

Energies 2020, 13(21), 5541; https://doi.org/10.3390/en13215541 - 22 Oct 2020

Cited by 9 | Viewed by 2338

Abstract

Large office buildings are responsible for a substantial portion of energy consumption in urban districts. However, thorough assessments regarding the Nordic countries are still lacking. In this paper we analyse the largest dataset to date for a Nordic office building, by considering a case study located in Stockholm, Sweden, that is occupied by nearly a thousand employees. Distinguishing the lighting and occupants’ appliances energy use from heating and cooling, we can estimate the impact of occupancy without any schedule data. A standard frequentist analysis is compared with Bayesian inference, and the according regression formulas are listed in tables that are easy to implement into building performance simulations (BPS). Monthly as well as seasonal correlations are addressed, showing the critical importance of occupancy. A simple method, grounded on the power drain measurements aimed at generating boundary conditions for the BPS, is also introduced; it shows how, for this type of data and number of occupants, no more complexities are needed in order to obtain reliable predictions. For an average year, we overestimate the measured cumulative consumption by only 4.7%. The model can be easily generalised to a variety of datasets. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

10 pages, 5330 KiB

Open AccessArticle

Hygrothermal Analysis of Masonry Wall with Reed Boards as Interior Insulation System

by Kadri Keskküla, Tambet Aru, Mihkel Kiviste and Martti-Jaan Miljan

Energies 2020, 13(20), 5252; https://doi.org/10.3390/en13205252 - 9 Oct 2020

Cited by 6 | Viewed by 2187

Abstract

When the masonry walls of buildings under heritage protection need to be restored and thermally improved, the only option is to use an interior insulation system. This is also the riskiest method of insulating walls in cold climates. Capillary active interior insulation systems have been proven to be the most reliable, minimizing the risk of mold growth and decay caused by condensation. They have also been proven to be less risky in wind-driven rain. The building studied is situated in a heritage-conservation area in downtown Tartu, Estonia, and therefore cannot be insulated from the exterior. This paper compares the hygrothermal performance of four different interior insulation systems with and without a heating cable and vapor barrier. In the first case, Isover Vario KM Duplex UV was placed between reed panels. In the second case, reed panels were used without the vapor barrier. Data loggers were applied between the reed panels and the original wall and inside the room to measure temperature and relative humidity in one-hour intervals. Exterior temperature and relative humidity values were taken from the Estonian University of Life Sciences Institute of Technology weather service station. In addition to the measurements taken in the case study building, calculations were made using heat-air-moisture (HAM) Delphin software to simulate the situation. The use of a smart vapor retarder (Isover Vario KM Duplex UV) with reed panels in the interior insulation system reduced the relative humidity level inside the wall. The vapor retarder improved the drying-potential compared to the interior insulation system without the vapor barrier. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

18 pages, 38585 KiB

Open AccessArticle

The Influence of Building Renovations on Indoor Comfort—A Field Test in an Apartment Building

by Paula Ala-Kotila, Terttu Vainio and Jarmo Laamanen

Energies 2020, 13(18), 4958; https://doi.org/10.3390/en13184958 - 22 Sep 2020

Cited by 8 | Viewed by 4041

Abstract

This article presents a field test of how deep renovation affects indoor climate quality. The studied apartment building was built in 1968 and is located in Finland, within the Nordic climate zone. The deep renovation included façade repair with extra insulation, new windows with trickle vents, new balcony glass and doors, and the installation of an exhaust air heat pump into the existing mechanical exhaust air ventilation. The indoor climate conditions and building envelope tightness were measured before and after the renovation. As a result of these energy renovation measures, the building envelope tightness improved by nearly 40% and the uncontrolled supply of air (draughts) decreased by approximately 24%. The overall energy consumption of the building decreased by 45%. Above all, the long testing period gives credibility to the study. The field test brought up the challenge of supplying an adequate amount of fresh air. This article highlights the fact that windows are part of a mechanical ventilation system if fresh air is not controlled by being led through inlet ducts. The supply air flow and volume must be ensured by correctly dimensioned valves, and therefore we stress the importance of the technical cooperation of technical designers. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Figure 1

31 pages, 3450 KiB

Open AccessArticle

EU Emission Targets of 2050: Costs and CO₂ Emissions Comparison of Three Different Solar and Heat Pump-Based Community-Level District Heating Systems in Nordic Conditions

by Hassam ur Rehman, Janne Hirvonen, Juha Jokisalo, Risto Kosonen and Kai Sirén

Energies 2020, 13(16), 4167; https://doi.org/10.3390/en13164167 - 12 Aug 2020

Cited by 20 | Viewed by 4296

Abstract

In Finland, old apartments (1980s) contribute toward emissions. The objective is to reduce CO₂ emissions to reach Europe’s targets of 2050. Three different centralized solar-based district heating systems integrated either with non-renovated or renovated old buildings in the community were simulated and compared against the reference city-level district heating system. The three proposed centralized systems were: Case 1: photovoltaic (PV) with a ground source heat pump (GSHP); Case 2: PV with an air-water heat pump (A2WHP); and Case 3: PV with A2WHPs, seasonal storage, and GSHPs. TRNSYS simulation software was used for dynamic simulation of the systems. Life cycle cost (LCC), CO₂ emissions and purchased electricity were calculated and compared. The results show that the community-level district heating system (Case 3) outperformed Case 1, Case 2, and the city-level district heating. With non-renovated buildings, the relative emissions reduction was 83% when the reference energy system was replaced with Case 3 and the emissions reduction cost was 3.74 €/kg.CO₂/yr. The relative emissions reduction was 91% when the buildings were deep renovated and integrated with Case 3 when compared to the reference system with non-renovated buildings and the emission reduction cost was 11.9 €/kg.CO₂/yr. Such district heating systems could help in meeting Europe’s emissions target for 2050. Full article

(This article belongs to the Special Issue Energy Performance and Indoor Climate in Buildings)

► Show Figures

Journal Menu

Journal Browser

Energy Performance and Indoor Climate in Buildings

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (11 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI