miun.sePublikasjoner
Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Primary energy implications of end-use energy efficiency measures in district heated buildings
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling. (Ecotechnology)
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling. (Ecotechnology)
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling. (Ecotechnology)
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för teknik och hållbar utveckling. (Ecotechnology)ORCID-id: 0000-0001-5356-7471
2011 (engelsk)Inngår i: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 43, nr 1, s. 38-48Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

In this study we explore the effects of end-use energy efficiency measures on different district heat production systems with combined heat and power (CHP) plants for base load production and heat-only boilers for peak and medium load productions. We model four minimum cost district heat production systems based on four environmental taxation scenarios, plus a reference district heat system used in Östersund, Sweden. We analyze the primary energy use and the cost of district heat production for each system. We then analyze the primary energy implications of end-use energy efficiency measures applied to a case-study apartment building, taking into account the reduced district heat demand, reduced cogenerated electricity and increased electricity use due to ventilation heat recovery. We find that district heat production cost in optimally-designed production systems is not sensitive to environmental taxation. The primary energy savings of end-use energy efficiency measures depend on the characteristics of the district heat production system and the type of end-use energy efficiency measures. Energy efficiency measures that reduce more of peak load than base load production give higher primary energy savings, because the primary energy efficiency is higher for CHP plants than for boilers. This study shows the importance of analyzing both the demand and supply sides as well as their interaction in order to minimize the primary energy use of district heated buildings.

sted, utgiver, år, opplag, sider
2011. Vol. 43, nr 1, s. 38-48
Emneord [en]
CHP plant; District heat production; Energy efficiency; Environmental taxations; Primary energy; Buildings
HSV kategori
Identifikatorer
URN: urn:nbn:se:miun:diva-11899DOI: 10.1016/j.enbuild.2010.07.029ISI: 000284682700005Scopus ID: 2-s2.0-78049480263OAI: oai:DiVA.org:miun-11899DiVA, id: diva2:337519
Tilgjengelig fra: 2010-08-06 Laget: 2010-08-06 Sist oppdatert: 2018-12-20bibliografisk kontrollert
Inngår i avhandling
1. Life cycle primary energy use and carbon emission of residential buildings
Åpne denne publikasjonen i ny fane eller vindu >>Life cycle primary energy use and carbon emission of residential buildings
2011 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Abstract [en]

In this thesis, the primary energy use and carbon emissions of residential buildings are studied using a system analysis methodology with a life cycle perspective. The analysis includes production, operation, retrofitting and end-of-life phases and encompasses the entire natural resource chain. The analysis  focuses, in particular, on to the choice of building frame material; the energy savings potential of building thermal mass; the choice of energy supply systems and their interactions with different energy-efficiency measures, including ventilation heat recovery systems; and the effectiveness of current energy-efficiency standards to reduce energy use in buildings. The results show that a wood-frame building has a lower primary energy balance than a concrete-frame alternative. This result is primarily due to the lower production primary energy use and greater bioenergy recovery benefits of wood-frame buildings. Hour-by-hour dynamic modeling of building mass configuration shows that the energy savings due to the benefit of thermal mass are minimal within the Nordic climate but varies with climatic location and the energy efficiency of the building. A concrete-frame building has slightly lower space heating demand than a wood-frame alternative, because of the benefit of thermal mass. However, the production and end-of-life advantages of using wood framing materials outweigh the energy saving benefits of thermal mass with concrete framing materials.

A system-wide analysis of the implications of different building energy-efficiency standards indicates that improved standards greatly reduce final energy use for heating. Nevertheless, a passive house standard building with electric heating may not perform better than a conventional building with district heating, from a primary energy perspective. Wood-frame passive house buildings with energy-efficient heat supply systems reduce life cycle primary energy use.

An important complementary strategy to reduce primary energy use in the building sector is energy efficiency improvement of existing buildings, as the rate of addition of new buildings to the building stock is low. Different energy efficiency retrofit measures for buildings are studied, focusing on the energy demand and supply sides, as well as their interactions. The results show that significantly greater life cycle primary energy reduction is achieved when an electric resistance heated building is retrofitted than when a district heated building is retrofitted. For district heated buildings, the primary energy savings of energy efficiency measures depend on the characteristics of the heat production system and the type of energy efficiency measures. Ventilation heat recovery (VHR) systems provide low primary energy savings where district heating is based largely on combined heat and power (CHP) production. VHR systems can produce substantial final energy reduction, but the primary energy benefit largely depends on the type of heat supply system, the amount of electricity used for VHR and the airtightness of buildings.

Wood-framed buildings have substantially lower life cycle carbon emissions than concrete-framed buildings, even if the carbon benefit of post-use concrete management is included. The carbon sequestered by crushed concrete leads to a significant decrease in CO2 emission. However, CO2 emissions from fossil fuels used to crush the concrete significantly reduce the carbon benefits obtained from the increased carbonation due to crushing. Overall, the effect of carbonation of post-use concrete is small. The post-use energy recovery of wood and the recycling of reinforcing steel both provide higher carbon benefits than post-use carbonation.

In summary, wood buildings with CHP-based district heating are an effective means of reducing primary energy use and carbon emission in the built environment.

sted, utgiver, år, opplag, sider
Östersund: Mittuniversitetet, 2011. s. 165
Serie
Mid Sweden University doctoral thesis, ISSN 1652-893X ; 115
HSV kategori
Identifikatorer
urn:nbn:se:miun:diva-14942 (URN)978-91-86694-57-9 (ISBN)
Disputas
2011-11-08, Q221, Campus Östersund, Östersund, 12:00 (engelsk)
Opponent
Veileder
Tilgjengelig fra: 2011-11-28 Laget: 2011-11-28 Sist oppdatert: 2012-07-30bibliografisk kontrollert
2. Energy efficiency of new residential buildings in sweden: Design and Modelling Aspects
Åpne denne publikasjonen i ny fane eller vindu >>Energy efficiency of new residential buildings in sweden: Design and Modelling Aspects
2014 (engelsk)Licentiatavhandling, med artikler (Annet vitenskapelig)
Abstract [en]

Energy security and climate change mitigation have been discussed in Sweden since the oil crisis in the 1970s. Sweden has since then increased its share of renewable energy resources to reach the highest level among the EU member states, but is still among the countries with the highest primary energy use per capita. Not least because of that, increasing energy efficiency is important and it is part of the Swedish long term environmental objectives. Large potential for improving energy efficiency can be found in the building sector, mainly in the existing building stock but also in newly constructed buildings

In this thesis, criteria for energy efficiency in new residential buildings are studied, several design aspects of residential buildings are examined, and possible further analysis from an energy system perspective discussed. Three case studies of existing residential buildings were analysed, including one detached house and multi-storey apartment buildings. The analysis was based on both energy simulations and measurements in residential buildings.

The results show that the calculated specific final energy demand of residential buildings, before they are built, is too rough an indicator to explicitly steer society toward lower final energy use in the building sector. One of the reasons is assumptions made during calculation before the buildings is built. Another reason is the interior building design. A design that includes relatively large areas of heated corridors, service and storage rooms will lower the specific final energy demand without improving the building energy efficiency, which might increase both the total final energy demand and the use of construction materials in the building sector.

Efficient thermal envelopes are essential in construction of energy efficient buildings, which include the thermal resistance and also the shape of the building. The shape factor of buildings was found to be an important variable for heat demand in buildings located in temperate and colder climates, particularly if they are exposed to strong winds.

From a system perspective, energy efficiency measures and the performance of the end use heating technology in buildings should be evaluated together with the energy supply system, including the dynamic interaction between them.

sted, utgiver, år, opplag, sider
Östersund: Mid Sweden University, 2014. s. 46
Serie
Mid Sweden University licentiate thesis, ISSN 1652-8948 ; 105
HSV kategori
Identifikatorer
urn:nbn:se:miun:diva-21933 (URN)978-91-87557-10-1 (ISBN)
Presentation
2014-05-05, Q 221, Akademigatan 1, Östersund, 10:00 (engelsk)
Opponent
Veileder
Tilgjengelig fra: 2014-05-16 Laget: 2014-05-13 Sist oppdatert: 2018-12-20bibliografisk kontrollert
3. Energy performance of residential buildings: projecting, monitoring and evaluating
Åpne denne publikasjonen i ny fane eller vindu >>Energy performance of residential buildings: projecting, monitoring and evaluating
2016 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Abstract [en]

Energy security and climate change mitigation have been discussed in Sweden since the oil crisis in the 1970s. Sweden has since then increased its share of renewable energy resources to reach the highest level among the EU member states, but is still among the countries with the highest primary energy use per capita. Not least because of that, increasing energy efficiency is important and it is part of the Swedish long term environmental objectives. Large potential for improving energy efficiency can be found in the building sector, mainly in the existing building stock but also in new constructions.

Buildings hold high costs for construction, service and maintenance. Still, their energy efficiency and thermal performance are rarely validated after construction or renovation. As energy efficiency become an important aspects in building design there is a need for accurate tools for assessing the energy performance both before and after building construction. In this thesis criteria for energy efficiency in new residential buildings are studied. Several building design aspects are discussed with regards to final energy efficiency, energy supply-demand interactions and social aspects. The results of this thesis are based on energy modelling, energy measurements and one questionnaire survey. Several existing residential buildings were used as case studies.

The results show that pre-occupancy calculations of specific final energy demand in residential buildings is too rough an indicator to explicitly steer towards lower final energy use in the building sector. Even post occupancy monitoring of specific final energy demand does not always provide a representative image of the energy efficiency of buildings and may result with large variation among buildings with similar thermal efficiency. A post occupancy method of assessing thermal efficiency of building fabrics using thermography is presented. The thermal efficiency of buildings can be increased by design with low shape factor. The shape factor was found to have a significant effect on the final energy demand of buildings and on the use of primary energy. In Nordic climates, atria in multi-storey apartment buildings is a design that have a potential to increase both energy efficiency (by lower shape factor) and enhance social interactions among the occupants.

sted, utgiver, år, opplag, sider
Östersund: Mittuniversitetet, 2016. s. 62
Serie
Mid Sweden University doctoral thesis, ISSN 1652-893X ; 238
HSV kategori
Identifikatorer
urn:nbn:se:miun:diva-27175 (URN)978-91-88025-52-4 (ISBN)
Disputas
2016-02-23, G1352, Östersund, 11:04 (engelsk)
Opponent
Veileder
Tilgjengelig fra: 2016-03-04 Laget: 2016-03-03 Sist oppdatert: 2018-12-20bibliografisk kontrollert

Open Access i DiVA

Fulltekst mangler i DiVA

Andre lenker

Forlagets fulltekstScopus

Personposter BETA

Gustavsson, LeifDodoo, AmbroseTruong, Nguyen LeDanielski, Itai

Søk i DiVA

Av forfatter/redaktør
Gustavsson, LeifDodoo, AmbroseTruong, Nguyen LeDanielski, Itai
Av organisasjonen
I samme tidsskrift
Energy and Buildings

Søk utenfor DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 463 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf