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Nair, Gireesh
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Azizi, S., Nair, G. & Olofsson, T. (2019). Analysing the house-owners’ perceptions on benefits and barriers of energy renovation in Swedish single-family houses. Energy and Buildings, 198, 187-196
Open this publication in new window or tab >>Analysing the house-owners’ perceptions on benefits and barriers of energy renovation in Swedish single-family houses
2019 (English)In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 198, p. 187-196Article in journal (Refereed) Published
Abstract [en]

Single-family houses offer a large potential for energy savings by energy renovation (ER). Homeowners’ motivation to implement ER derives from the benefits and barriers they perceive. Benefits are the positive consequences that can motivate homeowners to act and barriers are the challenges that demotivate them to undertake ER. Different benefits and barriers do not homogenously affect every homeowner. Identifying motivating benefits and demotivating barriers for each specific group among homeowners can shed lights on ER decision-making and enable policies that are more effective. The objective of this study is to contextualize the implementation of ER by understanding how the perceived benefits and barriers influence homeowners. This study links the expected consequences, which are benefits and barriers to the influential factors on ER, which are used to group the homeowners.

The analysis is based on a questionnaire survey mailed to 1550 owners of single-family houses in northern Sweden. The perceptions of homeowners on benefits and barriers of ER are significantly different between the groups that are motivated and unmotivated to implement ER. Despite the perceived importance of some of the benefits such as energy cost reduction, they may not be determinative for the homeowners’ decision to undertake ER. The homeowners are more likely to implement ER for reasons other than energy use reduction such as for improving the indoor environment. The barriers such as the difficulty of finding a low-interest loan and reliable information sources are found to impede the intention to implement ER among different groups. Policy implications to facilitate ER in single-family houses are discussed.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Energy efficient renovation, Investment decision, Perceptions, Implementation, House-owners, Sweden
National Category
Energy Systems
Research subject
environmental science
Identifiers
urn:nbn:se:umu:diva-160337 (URN)10.1016/j.enbuild.2019.05.034 (DOI)2-s2.0-85066929243 (Scopus ID)
Projects
renovatin center
Available from: 2019-06-17 Created: 2019-06-17 Last updated: 2019-08-14Bibliographically approved
Nair, G., Olofsson, T., Nordlund, A. & Hudson, C. (2019). Comparative evaluation of city dwellers' perspectives on household energy use based on housing tenure: survey results from Northern Sweden (1ed.). In: Johansson, Dennis, Bagge, Hans, Wahlström, Åsa (Ed.), Dennis Johansson, Hans Bagge, and Åsa Wahlström (Ed.), Cold climate HVAC 2018: sustainable buildings in cold climates. Paper presented at 9th International Cold Climate Conference, Sustainable new and renovated buildings in cold climates, Kiruna – Sweden 12-15, March 2018 (pp. 791-801). Switzerland: Springer Publishing Company
Open this publication in new window or tab >>Comparative evaluation of city dwellers' perspectives on household energy use based on housing tenure: survey results from Northern Sweden
2019 (English)In: Cold climate HVAC 2018: sustainable buildings in cold climates / [ed] Dennis Johansson, Hans Bagge, and Åsa Wahlström, Switzerland: Springer Publishing Company, 2019, 1, p. 791-801Conference paper, Published paper (Refereed)
Abstract [en]

The successful implementation of energy efficiency measures in the residential sector will depend to a large extent on the attitudes and perceptions of the end-users since they are the final decision maker. The tenure of the housing could influence the building occupants' perspectives on energy issues. In this study we conducted a comparative evaluation of perspectives on energy use of three categories of households: those living in single family houses, tenants and owners' of apartment. The analysis is based on responses to a mail-in questionnaire by approximately 650 residents in Umeå, Sweden. Majority of the respondents believed that their annual household energy use is less. Residents in single-family houses, as compared to the other two types of tenure of the housing, were more likely to believe their heat energy use as high and likely to take actions to reduce the energy use. Financial incentives such as subsidy or lower interest rate were preferred by most of single-family homeowners (45%) to motivate them to take actions to reduce energy use. While personalized information to reduce energy use and lower interest rate and reduced rent are preferred by more residents in the other two categories. The implications for promoting energy efficient measures based on housing tenure is discussed.

Place, publisher, year, edition, pages
Switzerland: Springer Publishing Company, 2019 Edition: 1
Series
Springer Proceedings in Energy, ISSN 2352-2534, E-ISSN 2352-2542
Keywords
Perception, Occupants, Energy efficiency
National Category
Civil Engineering
Identifiers
urn:nbn:se:umu:diva-152727 (URN)10.1007/978-3-030-00662-4_66 (DOI)978-3-030-00661-7 (ISBN)978-3-030-00662-4 (ISBN)
Conference
9th International Cold Climate Conference, Sustainable new and renovated buildings in cold climates, Kiruna – Sweden 12-15, March 2018
Available from: 2018-10-21 Created: 2018-10-21 Last updated: 2019-06-10Bibliographically approved
Azizi, S., Nair, G. & Olofsson, T. (2019). Demand-controlled energy systems in commercial and institutional buildings: a review of methods and potentials. In: eceee 2019 Summer Study on energy efficiency:: Is efficient sufficient?. Paper presented at eceee 2019 Summer Study, Belambra Presqu'île de Giens, France, 03–08 June, 2019 (pp. 1444-1450). European Council for an Energy Efficient Economy (ECEEE)
Open this publication in new window or tab >>Demand-controlled energy systems in commercial and institutional buildings: a review of methods and potentials
2019 (English)In: eceee 2019 Summer Study on energy efficiency:: Is efficient sufficient?, European Council for an Energy Efficient Economy (ECEEE), 2019, p. 1444-1450Conference paper, Published paper (Refereed)
Abstract [en]

Heating, ventilation and air-conditioning (HVAC) are by farthe most energy intensive systems in commercial and institutionalbuildings with office spaces. This makes HVAC systemsattractive targets for energy efficiency improvement. New technologicaladvancements can play significant role on improvingenergy efficiency. Such advancements have been also emergedin form of novel management and control strategies, whichmight lead to considerable energy savings with relatively minorinvestments. This paper evaluates demand control HVAC andlighting to assess the energy saving potential of upgrading theconventional building energy systems.

This paper provides a summary of different methods and occupancydetection technologies. A range of technologies andmethods are covered that vary in complexity, limitations andenergy saving potential. Additional benefits such as demandresponse are evaluated and other emerging applications arediscussed. Based on the review of methods and potentials, thepaper assesses the state of the art in demand controlled energysystems and suggests areas for further research.

Place, publisher, year, edition, pages
European Council for an Energy Efficient Economy (ECEEE), 2019
Series
eceee Summer Study proceedings, ISSN 1653-7025, E-ISSN 2001-7960
Keywords
occupancy detection, demand-side management
National Category
Energy Systems
Identifiers
urn:nbn:se:umu:diva-160341 (URN)978-91-983878-5-8 (ISBN)978-91-983878-4-1 (ISBN)
Conference
eceee 2019 Summer Study, Belambra Presqu'île de Giens, France, 03–08 June, 2019
Available from: 2019-06-17 Created: 2019-06-17 Last updated: 2019-06-18Bibliographically approved
Östin, R. & Nair, G. (2019). Energy performance and lessons learned from detailed measurement of a passive house preschool in cold climate. In: Is efficient sufficient?: eceee 2019 Summer Study on energy efficiency: Abstracts. Paper presented at European Council for an Energy Efficient Economy (ECEEE), France, June 3-8, 2019. (pp. 1433-1442). European Council for an Energy Efficient Economy (ECEEE)
Open this publication in new window or tab >>Energy performance and lessons learned from detailed measurement of a passive house preschool in cold climate
2019 (English)In: Is efficient sufficient?: eceee 2019 Summer Study on energy efficiency: Abstracts, European Council for an Energy Efficient Economy (ECEEE), 2019, p. 1433-1442Conference paper, Published paper (Refereed)
Abstract [en]

Public passive house buildings are rare in high northern latitudes. This study reports on extensive measurements and evaluations of the most northerly (640 N) built passive house preschool in Sweden. The two storied preschool, built in 2014, has a total heated floor area of 1407 m2. The building was certified according to the international passive house standard. The building has several smart solutions such as demand controlled ventilation of individual rooms and automatic solar shading system.

Energy measurements conducted during 2017-2018 showed that the preschool annually uses 44.4 kWhm-2, which is approximately 25 % lower than the passive house requirement for energy demand. However, the annual specific space heating requirement of 15 kWhm-2 and the peak heat power demand of 10 Wm-2 were not fulfilled. This non-compliance was mainly due to excessive ventilation during the heating season which was found to have 2.7 times higher air changes than the requirement in the Swedish building code. Furthermore, the building was found to be over heated from the sun during several occasions in a year. For example, excessive indoor air temperatures in the range 28 – 31°C were found during summer.

The study revealed that the default winter operation by turning off the ventilation system during nights and weekends is continued in other seasons as well. This practice was not a “smart” approach for the air handling units as it was found to be one of the reasons for high indoor temperatures during non-winter months. Also, a mismatch between the operation of the automatic shading device and the ventilation control units was noted.

The investigation shows that smart technical solutions in buildings may not be able to deliver its’ promised results if such systems are not monitored, adjusted and carefully evaluated. The paper identifies areas that need attention to ensure that a public building built to passive house standard actually deliver the energy efficiency it promises.

Place, publisher, year, edition, pages
European Council for an Energy Efficient Economy (ECEEE), 2019
Series
Ecee Summer Study Proceedings, ISSN 1653-7025, E-ISSN 2001-7960
Keywords
passive houses, energy measurement, building energy certification, energy efficiency action plans
National Category
Energy Systems
Identifiers
urn:nbn:se:umu:diva-159707 (URN)978-91-983878-0-3 (ISBN)978-91-983878-1-0 (ISBN)
Conference
European Council for an Energy Efficient Economy (ECEEE), France, June 3-8, 2019.
Available from: 2019-06-04 Created: 2019-06-04 Last updated: 2019-06-13Bibliographically approved
Nair, G. & Eklund, E. (2019). “Energy visualization” as a tool to influence the energy use in a municipality kitchen. In: eceee 2019 Summer Study on energy efficiency: Is efficient sufficient?, 3–8 June, Presqu’île de Giens, Hyères, France: . Paper presented at eceee 2019 Summer Study on energy efficiency (pp. 13-18). European Council for an Energy Efficient Economy (ECEEE)
Open this publication in new window or tab >>“Energy visualization” as a tool to influence the energy use in a municipality kitchen
2019 (English)In: eceee 2019 Summer Study on energy efficiency: Is efficient sufficient?, 3–8 June, Presqu’île de Giens, Hyères, France, European Council for an Energy Efficient Economy (ECEEE), 2019, p. 13-18Conference paper, Published paper (Refereed)
Abstract [en]

In Sweden, municipalities’ own and operate the kitchens that cook food for pre-schools, schools and the elderly care facilities. There are 68 kitchens in the municipality of Umeå and providing feedback to the kitchen staff on energy use could facilitate them to reduce the energy use in these facilities. Accordingly, an “energy visualization” project was initiated in one of the kitchen: Nordstjärnan, which is a newly built kitchen equipped with separate meters for appliances that continuously record the energy use.

For the “energy visualization” project, a visualization design software called “Siemens Control Point” is used. The software is integrated with the existing steering and control system and connected to almost all sensors/meters in the building.The electricity use data from the kitchen was collected for 5 months prior to installation of the “energy visualization” project to establish a base line for the energy use. The average electricity use is referred in this paper as “Electricity budget”, which is calculated for each kitchen appliance that has an electricity meter.

A trial was started in the kitchen from December 2018 onwards, wherein a display unit was designed to project the electricity use of the kitchen. The display unit, which is a large television screen, has different “slides”. For example, one of the slide is modelled to energy labelling. The energy labelling in the display has a rating from A+++ to D, which is calculated continuously based on the daily electricity use and the electricity budget. If the kitchen uses more electricity than budgeted then the rating will drop, and if the electricity use is less than the budget then the rating will increase. Furthermore, depending upon the energy performance of the kitchen the visualization screens also display “smileys” which are used as injunctive norms.

Place, publisher, year, edition, pages
European Council for an Energy Efficient Economy (ECEEE), 2019
Series
eceee 2019 eceee Summer Study proceedings, ISSN 2001-7960
Keywords
Sweden, energy use, visualisation, displays
National Category
Energy Systems
Research subject
Earth Sciences with Specialization Environmental Analysis
Identifiers
urn:nbn:se:umu:diva-159543 (URN)978-91-983878-4-1 (ISBN)
Conference
eceee 2019 Summer Study on energy efficiency
Projects
eLighthouse
Available from: 2019-05-30 Created: 2019-05-30 Last updated: 2019-06-12Bibliographically approved
Nordlund, A., Nair, G., Hudson, C. & Olofsson, T. (2018). Att utveckla en stadsdel på ett hållbart sätt: en fråga om energi, transporter och människor. Umeå: Transportforskningsenheten, Umeå Universitet
Open this publication in new window or tab >>Att utveckla en stadsdel på ett hållbart sätt: en fråga om energi, transporter och människor
2018 (Swedish)Report (Other academic)
Place, publisher, year, edition, pages
Umeå: Transportforskningsenheten, Umeå Universitet, 2018. p. 59
Series
TRUM, ISSN 1403-6924 ; 2018:1
Keywords
Hållbar stadsutveckling, Universitetsstaden, Attityder och beteende, Energianvändning, Resbeteende, Åtgärder, Samhällsplanering
National Category
Social Sciences Interdisciplinary
Identifiers
urn:nbn:se:umu:diva-147957 (URN)
Projects
Umeå – En testbädd för hållbar stadsutveckling
Funder
Swedish Energy Agency
Available from: 2018-05-23 Created: 2018-05-23 Last updated: 2018-06-19Bibliographically approved
Azizi, S., Nair, G. & Olofsson, T. (2018). Comparative Study of Influential Factors on Implementation of Energy Efficiency Measures in Single-Family Houses in Cold Climate. In: : . Paper presented at 2018 ACEEE Summer Study in Energy Efficiency in Buildings, Pacific Grove, CA, August 12-17, 2018. ACEEE - American Council for Energy-Efficient Economy
Open this publication in new window or tab >>Comparative Study of Influential Factors on Implementation of Energy Efficiency Measures in Single-Family Houses in Cold Climate
2018 (English)Conference paper, Published paper (Refereed)
Abstract [en]

A combination of factors, which include occupants and building related aspects, could motivate homeowners to implement energy renovation (ER). This study applies a comparative approach to assess perspectives of single-family homeowners towards different energy efficiency measures (EEMs). The aim is to unveil the factors that are effective on the residents’ attitude and decision making to implement an EEM or a set of EEMs. The analysis is based on a questionnaire survey conducted during spring 2017 among1550 owners of single-family houses in seven municipalities in northern Sweden. Approximately, 35% of respondents expressed their interest to install energy efficient household appliances and solar photovoltaic (PV) systems. The analysis suggests significant relations between the homeowners’ interest to implement thermal envelope measures and the quality of the house such as age and indoor environmental problems such as cold surfaces. The group of respondents, who reported their heating cost to be high, are more likely to be interested in implementing thermal envelope measures than other measures such as HVAC. Several socio-economic factors are found to be significantly related with homeowners’ interest to implement EEMs.

Place, publisher, year, edition, pages
ACEEE - American Council for Energy-Efficient Economy, 2018
Keywords
Energy efficient renovation
National Category
Energy Engineering
Identifiers
urn:nbn:se:umu:diva-151878 (URN)
Conference
2018 ACEEE Summer Study in Energy Efficiency in Buildings, Pacific Grove, CA, August 12-17, 2018
Funder
European Regional Development Fund (ERDF)
Available from: 2018-09-14 Created: 2018-09-14 Last updated: 2019-06-14Bibliographically approved
Allard, I., Olofsson, T. & Nair, G. (2018). Energy evaluation of residential buildings: Performance gap analysis incorporating uncertainties in the evaluation methods. Building Simulation, 11(4), 725-737
Open this publication in new window or tab >>Energy evaluation of residential buildings: Performance gap analysis incorporating uncertainties in the evaluation methods
2018 (English)In: Building Simulation, ISSN 1996-3599, E-ISSN 1996-8744, Vol. 11, no 4, p. 725-737Article in journal (Refereed) Published
Abstract [en]

Calculation and measurement-based energy performance evaluations of the same building often provide different results. This difference is referred as "the performance gap". However, a large performance gap may not necessarily mean that there are flaws in the building or deviations from the intended design. The causes for the performance gap can be analysed by calibrating the simulation model to measured data. In this paper, an approach is introduced for verifying compliance with energy performance criteria of residential buildings. The approach is based on a performance gap analysis that takes the uncertainties in the energy evaluation methods into consideration. The scope is to verify building energy performance through simulation and analysis of measured data, identifying any performance gap due to deviations from the intended design or flaws in the finished building based on performance gap analysis. In the approach, a simulation model is calibrated to match the heat loss coefficient of the building envelope [kWh/K] instead of the measured energy. The introduced approach is illustrated using a single-family residential building. The heat loss coefficient was found useful towards identifying any deviations from the intended design or flaws in the finished building. The case study indicated that the method uncertainty was important to consider in the performance gap analysis and that the proposed approach is applicable even when the performance gap appears to be non-existing.

Place, publisher, year, edition, pages
Tsinghua University Press, 2018
Keywords
performance gap, energy signature, calibration, simulation, design criteria
National Category
Energy Engineering
Identifiers
urn:nbn:se:umu:diva-150666 (URN)10.1007/s12273-018-0439-7 (DOI)000435421700008 ()2-s2.0-85048691979 (Scopus ID)
Note

Originally included in thesis in manuscript form with title A methodology to investigate the building energy performance gap

Available from: 2018-08-20 Created: 2018-08-20 Last updated: 2018-11-13Bibliographically approved
Olofsson, T., Nair, G. & Azizi, S. (2018). Enkät om renovering och energieffektivisering [Review]. Energi & Miljö (1)
Open this publication in new window or tab >>Enkät om renovering och energieffektivisering
2018 (Swedish)In: Energi & Miljö, no 1Article, book review (Other (popular science, discussion, etc.)) Published
Place, publisher, year, edition, pages
Stockholm: , 2018
National Category
Energy Systems
Identifiers
urn:nbn:se:umu:diva-145549 (URN)
Available from: 2018-03-09 Created: 2018-03-09 Last updated: 2019-06-17
Nair, G., Azizi, S. & Olofsson, T. (2017). A management perspective on energy efficient renovations in Swedish multi-family buildings. Energy Procedia, 132, 994-999
Open this publication in new window or tab >>A management perspective on energy efficient renovations in Swedish multi-family buildings
2017 (English)In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 132, p. 994-999Article in journal (Refereed) Published
Abstract [en]

Sweden has around 2.5 million dwellings in multi-family buildings, which constitute about 55% of the total dwelling units. The multi-family building ownership in Sweden can be categorized into municipal, private and co-operative ownership. Approximately 40% of apartments in multi-family buildings belong to municipal housing companies, while the rest is equally shared by private companies and co-operative housing associations. These organizations have different priorities, limitations and concerns related to energy renovations. Accordingly, in this sector the decisions to invest in energy efficiency improvement depends to a large extent on the type of ownership.

In this study we analyzed the perspectives of different types of building ownership on energy efficient renovation. The analysis is based on detailed interviews of 4 senior managers representing the multi-family buildings under different ownership categories. Along with this we also interviewed a municipality energy adviser. All the interviewees are based in in North Sweden. The drivers to facilitate the rate of adoption of energy renovation in such buildings are discussed.

Place, publisher, year, edition, pages
Elsevier, 2017
Keywords
Energy renovations, barriers, multi-family buildings, decisions, Sweden
National Category
Energy Systems
Identifiers
urn:nbn:se:umu:diva-133613 (URN)10.1016/j.egypro.2017.09.699 (DOI)000426435500166 ()2-s2.0-85033386266 (Scopus ID)
Available from: 2017-04-14 Created: 2017-04-14 Last updated: 2018-06-11Bibliographically approved
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