| 1. |
- Averfalk, Helge, 1988-, et al.
(författare)
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Low-Temperature District Heating Implementation Guidebook : Final Report of IEA DHC Annex TS2. Implementation of Low-Temperature District Heating Systems
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This guidebook was written between 2018 and 2021 by seventeen authors that used approximately 15 000 hours of work within the IEA DHC TS2 annex. The content is based on more than 250 literature references and 165 inspiration initiatives to obtain lower temperatures in buildings and heat distribution networks. The author group wrote 40 internal documents about early implementations of low-temperature district heating. Fifteen of these early implementations are presented in this guidebook.The guidebook contains aggregated information about the main economic drivers for low-temperature district heating. It shows how to obtain lower temperatures in heating systems inside existing and new buildings, as well as in existing and new heat distribution networks. An applied study of a campus system in Darmstadt shows the possibility of reducing temperatures in an existing heat distribution network with rather high temperatures. The competitiveness of low-temperature district heating is explored by analysing business models and heat distribution costs. Early adopters of low-temperature district heating are presented by examples and by identified transition strategies. Five groups of network configurations with fourteen variants are presented to be used for low-temperature district heating. Finally, all 165 identified inspiration initiatives and all 137 locations mentioned are listed.
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| 2. |
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| 3. |
- Dalla Rosa, Alessandro, et al.
(författare)
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Annex X Final report : Toward 4th Generation District Heating: Experience and Potential of Low-Temperature District Heating
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Background and ObjectiveThe evolution of district heating (DH) has gone through three generations since the first introduction of distirct heating. It is characterized by the type of transport media and the network temperature levels: the 1st generation DH system is steam-based system, the 2nd generation DH uses high network supply temperature above 100oC, and the 3rd generation DH represents the current DH system with medium network supply temperature between 80oC to 100oC. Up until now, the 4th generation DH as the low-temperature district heating (LTDH) is emerging as a new system which is going to replace the existing 3rd generation DH system. Comparing with the existing DH system, the LTDH reduces the network supply temperature down to consumer required temperature level, thus greatly improves the quality match between the energy supply and the energy demand. Meanwhile, LTDH coupling with reduced network temperature and well-designed DH network can reduce network heat loss by up to 75% comparing with the current system. This makes DH economically competitive comparing with local heat generation units in the areas with low heat density or with low-energy buildings.The traditional approach to evaluating a DH system often focuses on the production/supply aspect and only afterwards on the final users. The LTDH concept switches the perspective, starting from end-user thermal comfort and a quality match between energy supply and energy consumption, and aiming to find the best and most economical way to satisfy the heat demand through efficient distribution networks and supply systems based on waste heat and RE. The new concept therefore starts by identifying suitable in-house substations for low-energy-demand buildings at low supply temperature, goes back to design efficient and reliable networks, and finally considers environmentally-friendly heat production units.This report describes the concept of LTDH, collects and discusses successful examples of implementation LTDH in the building heating sector. The objective of this report is to raise awareness and provide insights that will stimulate the research, development and implementation of LTDH systems. It will help to increase public recognition and assist policy makers and energy planners, both at local and governmental level, in promoting cost-effective and environmentally friendly DH systems, and in planning and realizing long-term sustainable urban area development. To this end, the report addresses the following research issues:1. What are the main advantages of LTDH?2. What technology options are available for LTDH, and what are the associated challenges to consider?3. How can the risk of Legionella be mitigated in LTDH?4. What lessons can be learned from early LTDH projects?5. What heat distribution costs are associated with LTDH?
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| 4. |
- Dodoo, Ambrose
(författare)
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Life cycle primary energy use and carbon emission of residential buildings
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- 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.
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| 5. |
- Haavik, Trond, et al.
(författare)
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New business models for holistic renovation solutions of single family houses
- 2011
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Konferensbidrag (refereegranskat)abstract
- Single family houses represent the biggest potential for energy savings within residential buildingsin the Nordic countries. In earlier research project [1] it highlighted that there is a missing linkbetween the single family house owner and various segregated offers of single solutions forrenovation and/or energy efficiency installations. In the two international research projectsSuccessFamiles and One Stop Shop, establishment of new business models as pilots for bridgingthis gap are now being monitored.Two of the pilots as “one stop shops”, a retailer chain in Finland and a daughter company of aNorwegian manufacturer of insulation, are described and discussed.A key issue for any business model which offers an integrated service from analysis of the houseand recommendations for measures is the trustworthiness of the supplier.As a holistic energy efficient renovation project is a “new” and unknown service to single familyhouse owner and at same time a costly investment, it is important for the suppliers to findadequate ways of communicating through each phase of the buying process. There are variouschallenges in each of the phases which have to be solved differently.
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| 6. |
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| 7. |
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| 8. |
- Liv, Per, et al.
(författare)
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Accuracy and precision of variance components in occupational posture recordings : a simulation study of different data collection strategies
- 2012
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Ingår i: BMC Medical Research Methodology. - : Springer Science and Business Media LLC. - 1471-2288. ; 12:1, s. 58-58
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Tidskriftsartikel (refereegranskat)abstract
- Background. Information on exposure variability, expressed as exposure variance components, is of vital use in occupational epidemiology, including informed risk control and efficient study design. While accurate and precise estimates of the variance components are desirable in such cases, very little research has been devoted to understanding the performance of data sampling strategies designed specifically to determine the size and structure of exposure variability. The aim of this study was to investigate the accuracy and precision of estimators of betweensubjects, between-days and within-day variance components obtained by sampling strategies differing with respect to number of subjects, total sampling time per subject, number of days per subject and the size of individual sampling periods. Methods. Minute-by-minute values of average elevation, percentage time above 90degrees and percentage time below 15degrees were calculated in a data set consisting of measurements of right upper arm elevation during four full shifts from each of 23 car mechanics. Based on this parent data, bootstrapping was used to simulate sampling with 80 different combinations of the number of subjects (10, 20), total sampling time per subject (60, 120, 240, 480 minutes), number of days per subject (2, 4), and size of sampling periods (blocks) within days (1, 15, 60, 240 minutes). Accuracy (absence of bias) and precision (prediction intervals) of the variance component estimators were assessed for each simulated sampling strategy. Results. Sampling in small blocks within days resulted in essentially unbiased variance components. For a specific total sampling time per subject, and in particular if this time was small, increasing the block size resulted in an increasing bias, primarily of the between-days and the within-days variance components. Prediction intervals were in general wide, and even more so at larger block sizes. Distributing sampling time across more days gave in general more precise variance component estimates, but also reduced accuracy in some cases. Conclusions. Variance components estimated from small samples of exposure data within working days may be both inaccurate and imprecise, in particular if sampling is laid out in large consecutive time blocks. In order to estimate variance components with a satisfying accuracy and precision, for instance for arriving at trustworthy power calculations in a planned intervention study, larger samples of data will be required than for estimating an exposure mean value with a corresponding certainty
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| 9. |
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| 10. |
- Liv, Per, 1979-, et al.
(författare)
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Theoretical and empirical efficiency of sampling strategies for estimating upper arm elevation
- 2011
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Ingår i: Annals of Occupational Hygiene. - : Oxford University Press (OUP). - 0003-4878 .- 1475-3162. ; 55:4, s. 436-449
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To investigate the statistical efficiency of strategies for sampling upper arm elevation data, which differed with respect to sample sizes and sample allocations within and across measurement days. The study was also designed to compare standard theoretical predictions of sampling efficiency, which rely on several assumptions about the data structure, with 'true' efficiency as determined by bootstrap simulations.METHODS: Sixty-five sampling strategies were investigated using a data set containing minute-by-minute values of average right upper arm elevation, percentage of time with an arm elevated <15°, and percentage of time with an arm elevated >90° in a population of 23 house painters, 23 car mechanics, and 26 machinists, all followed for four full working days. Total sample times per subject between 30 and 240 min were subdivided into continuous time blocks between 1 and 240 min long, allocated to 1 or 4 days per subject. Within day(s), blocks were distributed using either a random or a fixed-interval principle. Sampling efficiency was expressed in terms of the variance of estimated mean exposure values of 20 subjects and assessed using standard theoretical models assuming independence between variables and homoscedasticity. Theoretical performance was compared to empirical efficiencies obtained by a nonparametric bootstrapping procedure.RESULTS: We found the assumptions of independence and homoscedasticity in the theoretical model to be violated, most notably expressed through an autocorrelation between measurement units within working days. The empirical variance of the mean exposure estimates decreased, i.e. sampling efficiency increased, for sampling strategies where measurements were distributed widely across time. Thus, the most efficient allocation strategy was to organize a sample into 1-min block collected at fixed time intervals across 4 days. Theoretical estimates of efficiency generally agreed with empirical variances if the sample was allocated into small blocks, while for larger block sizes, the empirical 'true' variance was considerably larger than predicted by theory. Theory overestimated efficiency in particular for strategies with short total sample times per subject.CONCLUSIONS: This study demonstrates that when exposure data are autocorrelated within days-which we argue is the major reason why theory overestimates sampling performance-sampling efficiency can be improved by distributing the sample widely across the day or across days, preferably using a fixed-interval strategy. While this guidance is particularly valid when small proportions of working days are assessed, we generally recommend collecting more data than suggested by theory if a certain precision of the resulting exposure estimate is needed. More data per se give a better precision and sampling larger proportion(s) of the working day(s) also alleviate the negative effects of possible autocorrelation in data.
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| 11. |
- Lund, Henrik, et al.
(författare)
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4th Generation District Heating (4GDH) : Integrating smart thermal grids into future sustainable energy systems
- 2014
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Ingår i: Energy. - London, United Kingdom : Elsevier. - 0360-5442 .- 1873-6785. ; 68, s. 1-11
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Tidskriftsartikel (refereegranskat)abstract
- This paper defines the concept of 4th Generation District Heating (4GDH) including the relations to District Cooling and the concepts of smart energy and smart thermal grids. The motive is to identify the future challenges of reaching a future renewable non-fossil heat supply as part of the implementation of overall sustainable energy systems. The basic assumption is that district heating and cooling has an important role to play in future sustainable energy systems – including 100 percent renewable energy systems – but the present generation of district heating and cooling technologies will have to be developed further into a new generation in order to play such a role. Unlike the first three generations, the development of 4GDH involves meeting the challenge of more energy efficient buildings as well as being an integrated part of the operation of smart energy systems, i.e. integrated smart electricity, gas and thermal grids. © 2014 Elsevier Ltd.
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| 12. |
- Lund, Henrik, et al.
(författare)
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The status of 4th generation district heating : Research and results
- 2018
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Ingår i: Energy. - London : Elsevier. - 0360-5442 .- 1873-6785. ; 164, s. 147-159
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Tidskriftsartikel (refereegranskat)abstract
- This review article presents a description of contemporary developments and findings related to the different elements needed in future 4th generation district heating systems (4GDH). Unlike the first three generations of district heating, the development of 4GDH involves meeting the challenge of more energy efficient buildings as well as the integration of district heating into a future smart energy system based on renewable energy sources. Following a review of recent 4GDH research, the article quantifies the costs and benefits of 4GDH in future sustainable energy systems. Costs involve an upgrade of heating systems and of the operation of the distribution grids, while benefits are lower grid losses, a better utilization of low-temperature heat sources and improved efficiency in the production compared to previous district heating systems. It is quantified how benefits exceed costs by a safe margin with the benefits of systems integration being the most important. © 2018 Elsevier Ltd
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| 13. |
- Mahapatra, Krushna, 1974-, et al.
(författare)
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Business models for full service energy efficient renovation of single family houses in Nordic countries
- 2012
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Ingår i: ICAE2012. ; , s. 593-602
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Konferensbidrag (refereegranskat)abstract
- In Nordic countries significant primary energy efficiency potential exists in houses built before 1980. These old houses need to be renovated, which provides an opportunity for implementation of energy efficiency measures. However, there are several economic and market barriers and the renovation market are dominated by handicraft-based individual solutions. In this project we analyze the opportunities for implementation of one-stop-shop business models where an overall contractor offers full-service renovation packages including consulting, independent energy audit, renovation work, follow-up (independent quality control and commissioning) and financing.A comparative assessment of emerging business models shows that different types of actors (renovation company, insulation company, energy utility, building product warehouse) can provide such a service. Financing is included in some models. There are differences in how customers are contacted, while the similarities are more on how the service is provided. A main challenge is how to secure independent advising and there is there is uncertainty over who will be responsible for guarantee of the renovation work if the service provider goes bankrupt.Even though there is strong business potential for one-stop-shop energy renovation concept, still it has been somewhat difficult to start or run such a business. Various options to overcome the barriers to promote energy efficient renovation of detached houses are discussed.
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| 14. |
- Mahapatra, Krushna, 1974-, et al.
(författare)
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Business models for full service energy renovation of single family houses in Nordic countries
- 2013
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Ingår i: Applied Energy. - : Elsevier. - 0306-2619 .- 1872-9118. ; 112, s. 1558-1565
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Tidskriftsartikel (refereegranskat)abstract
- In Nordic countries significant primary energy saving potential exists in houses built before 1980. These old houses need to be renovated, which provides an opportunity for implementation of energy efficiency measures. However, there are several economic and market hindrances and the renovation markets are dominated by handicraft-based individual solutions. In this paper we have analyzed the opportunities for implementation of one-stop-shop business models where an overall contractor offers full-service renovation packages including consulting, independent energy audit, renovation work, follow-up (independent quality control and commissioning) and financing. A comparative assessment of emerging business models in the Nordic countries shows that different types of actors can provide such a service. Financing is included in some models. There are differences in how customers are contacted, while the similarities are on how the service is provided. Even though there is strong business potential for one-stop-shop energy renovation concept, still it has been somewhat difficult to start or run such a business. Various options to overcome the hindrances to promote energy efficient renovation of detached houses are discussed.
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| 15. |
- Mahapatra, Krushna, 1974-, et al.
(författare)
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One-stop-shop service for sustainable renovation of single family house : Summary Report
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Nordic project “Successful Sustainable Renovation Business for Single-Family Houses (SuccessFamilies)”, with participants from Denmark, Finland, Norway and Sweden, deals with development of business models for full service energy efficient renovation of detached houses in Nordic countries. The background to this project is that the majority of these houses are more than 30 years old and need to be renovated, which provides opportunity for implementation of energy efficiency measures. The renovation market is dominated by handicraft-based individual solutions. There is a need for onestop-shop business models where an overall contractor offers full-service renovation packages including consulting, independent energy audit, renovation work, independent quality control and commissioning, and financing. There is a significant business potential for such a model as the volume of renovation market for single-family houses can reach hundreds of million Euros per year in each Nordic country. The project team analysed emerging business models to offer full-service renovation packages in the Nordic countries. A comparative assessment shows that different types of actors (renovation company, insulation company, energy utility, building product warehouse) can provide such a service. There are differences in how customers are contacted, while the similarities are more on how the service is provided. A main challenge is how to secure independent advising. Even though there is strong business potential for one-stop-shop energy renovation concept, still it has been somewhat difficult to start or run such a business. Various options to overcome the barriers to promote energy efficient renovation of detached houses are discussed in the final report.
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| 16. |
- Mahapatra, Krushna, 1974-, et al.
(författare)
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Report on business models for one-stop-shop service for sustainable renovation of single family house, Deliverable D3.2 : Successful Sustainable Renovation Business for Single-Family Houses – SuccessFamilies
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In Nordic countries significant primary energy efficiency potential exists in houses built before 1980. These houses are more than 30 years old and need to be renovated. This provides an opportunity for implementation of energy efficiency measures, but the renovation market is dominated by handicraft-based individual solutions. There is a need for one-stop-shop business models where an overall contractor offers full-service renovation packages including consulting, independent energy audit, renovation work, follow-up (independent quality control and commissioning) and financing. There is a significant business potential for such a model as the renovation market for single-family houses could be in the order of hundreds of million Euros per year in each Nordic country. Homeowners will get an improved quality renovated house with little risk or responsibility which usually is the case with traditional renovations, the energy cost will be reduced, market value of the house is likely to increase, mortgage banks will have a safer asset and there are societal benefits in terms of reduced energy use and greenhouse gas emission. However, there is uncertainty over who will be responsible for guarantee of the renovation work if the service provider goes bankrupt. Insurance companies could be involved to address this issue.The aim of the report is to analyze and develop one-stop-shop business models to offer full-service renovation packages in the Nordic countries. The report will contribute to identify potential models that can be tested in pilot studies and will be an important source of market information for companies planning to develop a one-stop-shop concept.A comparative assessment of models proposed in the Nordic countries shows that different type of actors may play the key role in a one-stop-shop for energy efficient renovation of single-family houses. In some models the service provider collaborates with financing institutions to provide renovation financing. There are differences on how customers are contacted, while the similarities are more on how the service is provided. A main challenge is how to secure independent advising.Even though there is strong business potential for one-stop-shop energy renovation concept, still it has been somewhat difficult to start or run such a business. One of the main reasons is the uncertainties about the customer base. One way to attract more customers is to offer subsidies for energy efficiency measures. In Denmark, Sweden and Finland there are tax deductions for labour cost for home renovation and other household work. An amendment to such programs to incorporate specific requirements regarding energy efficiency of implemented measures could be a way to increase homeowners’ interest in energy efficient renovation.A guarantee on energy or energy cost saving may encourage energy efficient renovation of houses as energy cost saving is one of the most important factors in the homeowners’ decision to implement energy efficiency measures. But, at present it is less likely that such guarantee will be given as the full service energy renovation concept is yet to be tested and not enough experience exists regarding energy savings potential in the context of varying household energy behaviour. However, such concepts exist for industrial and public buildings (the ESCO concept) and are emerging for residential buildings. Highlighting the energy (e.g. cost reduction) and non-energy benefits (improved thermal comfort or indoor air quality) of energy efficiency improvements may create customer interest in energy efficient renovations.One way to kickstart the market is to provide public funding for few demonstration projects to test different business models, e.g. those identified in this report. Such projects will bring together actors interested in one-stop-shop concept and they will gain some experience. In such demonstration projects the full-scale energy renovation actions could be realised in shorter timeframe than in traditional piecemeal renovations. Advertisement of results of successful demonstration projects may attract more customers and entrepreneurs.Existing models in Denmark and Finland include financing by the service providers in collaboration with financing institutions. Still, mortgage financing is the most cost efficient option to finance energy efficiency renovation of single-family houses (Mahapatra et al. 2011). However, the need to selffinance the amount not covered in the mortgage loan may not encourage homeowners to go for energy efficiency renovation. This could be addressed if government provides soft loans or subsidies to cover the investment cost beyond the mortgage (base) loan. Attention should be given to the limitation of mortgage financing for energy efficient renovation of recently bought houses. Banks may consider an energy efficient renovation plan prepared by an entrepreneur and pre-evaluate the postrenovation value of the house in collaboration with real estate agents. This valuation could form the basis for the bank to confirm the homeowner and the entrepreneur that certain amount of investment cost would be covered by mortgage refinancing.
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| 17. |
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| 18. |
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| 19. |
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| 20. |
- Mathiassen, Svend Erik, et al.
(författare)
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Task-based estimation of mechanical job exposure in occupational groups
- 2005
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Ingår i: Scandinavian Journal of Work, Environment and Health. - 0355-3140 .- 1795-990X. ; 31:2, s. 138-51
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: This study examined the validity of a common belief in epidemiology with respect to work-related musculoskeletal disorders, that individual mechanical job exposure is better estimated from tasks performed in the job than from the mean exposure of the occupational group. METHODS: Whole-day recordings of upper trapezius electromyography were obtained from 24 cleaners and 23 office workers. Trapezius activity was analyzed in the level (gap time) and frequency (jerk time) dimensions. On the same day, the job of each person was divided into periods of active work and breaks by means of continuous observations. The bootstrap re-sampling technique was used with this database to compare task-based job exposure estimates with estimates based on the occupational mean. For a particular person, the task-based estimate was obtained by combining the average work and break exposures in the occupation with the personal time proportions of the two tasks in the job. RESULTS: The task-based estimates were, in general, equivalent to, or less correct than, occupation-based estimates for both exposure parameters in both occupations and for individual exposures, as well as for group means. This was the result in spite of significant and consistent exposure differences between work and breaks, in particular among the cleaners. CONCLUSIONS: Even if task exposure contrasts are large, task-based estimates of job exposures can be less correct than estimates based on the occupational mean. Since collecting and processing task information is costly, it is recommended that task-based modeling of mechanical exposure be implemented in studies only after careful examination of its possible benefits.
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| 21. |
- Persson, Johannes, 1981-
(författare)
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Low-energy buildings : energy use, indoor climate and market diffusion
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Low-energy buildings have, in recent years, gained attention and moved towards a large-scale introduction in the residential sector. During this process, national and international criteria for energy use in buildings have become stricter and the European Union has through the Energy Performance of Buildings Directive imposed on member states to adapt their building regulations for ‘Nearly Zero Energy Buildings’, which by 2021 should be standard for new buildings.With a primary focus on new terraced and detached houses, this thesis analyses how the concept of low-energy buildings may be further developed to reduce the energy use in the residential sector. The main attention is on the technical performance in terms of indoor climate and heat consumption as well as on the market diffusion of low-energy buildings into the housing market.A multidisciplinary approach is applied, which here means that the concept of low-energy buildings is investigated from different perspectives as well as on different system levels. The thesis thus encompasses methods from both engineering and social sciences and approaches the studied areas through literature surveys, interviews, assessments and simulations.The thesis reveals how an increased process integration of the building’s energy system can improve the thermal comfort in low-energy buildings. Moreover, it makes use of learning algorithms – in this case artificial neural networks – to study how the heat consumption can be predicted in a low-energy building in the Swedish climate. The thesis further focuses on the low-energy building as an element in our society and it provides a market diffusion analysis to gain understanding of the contextualisation process. In addition, it suggests possible approaches to increase the market share of low-energy buildings.
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| 22. |
- Svendsen, Susanne Wulff, et al.
(författare)
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Work above shoulder level and degenerative alterations of the rotator cuff tendons : a magnetic resonance imaging study.
- 2004
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Ingår i: Arthritis and rheumatism. - : Wiley. - 0004-3591 .- 1529-0131. ; 50:10, s. 3314-22
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To determine whether work performed with the arms in a highly elevated position is associated with alterations in the rotator cuff tendons as assessed by magnetic resonance imaging (MRI). METHODS: A cross-sectional study was performed in a historical cohort of male machinists, car mechanics, and house painters. The participants were right-handed, ages 40-50 years, and had been employed in their trades for not less than 10 years. Seventy-one percent of invited subjects participated (136 of 192). Lifetime upper arm elevation was assessed by direct measurements combined with individual work histories obtained by questionnaire and from registry data. Supraspinatus tendinopathy was evidenced by MRI signal intensity changes and morphologic alterations. Infraspinatus and subscapularis tendinopathy were also assessed. Additional outcomes were acromioclavicular joint degeneration and humeral head cysts. The MRI findings were evaluated by radiologists who were blinded to exposure status and symptoms. RESULTS: An exposure-response relationship was found between lifetime upper arm elevation and supraspinatus tendinopathy, with an age-adjusted odds ratio of 1.27 (95% confidence interval 1.02-1.60) for a 5-month increase in the total number of full-time working months spent with the arm elevated >90 degrees . CONCLUSION: Work with the arms in a highly elevated position is associated with MRI-diagnosed alterations in the supraspinatus tendon. By demonstrating the first part of a possible biologic pathway, the study corroborates the work-relatedness of rotator cuff disorders.
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| 23. |
- Svendsen, SW, et al.
(författare)
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Work related shoulder disorders: quantitative exposure-response relations with reference to arm posture
- 2004
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Ingår i: Occupational and Environmental Medicine. - : BMJ. - 1470-7926 .- 1351-0711. ; 61:10, s. 844-853
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Tidskriftsartikel (refereegranskat)abstract
- Aims: To determine quantitative exposure-response relations between work with highly elevated arms and supraspinatus tendinitis, shoulder pain with disability, and shoulder pain without disability. Methods: A cross sectional study was conducted in a historical cohort of 1886 males from three occupational groups. Exposure measurements were performed for four consecutive working days in a random sample of 72 currently employed subjects. Individual work histories were obtained by questionnaire and register data. Health status was ascertained by physical examination blinded towards exposure and symptoms. Data were analysed by generalised estimating equation and multiple logistic regression with adjustment for potential confounders. Results: For current upper arm elevation above 90degrees, a duration increment of 1% of the daily working hours was associated with odds ratios of 1.23 (95% CI 1.10 to 1.39) for supraspinatus tendinitis, 1.16 ( 95% CI 1.08 to 1.24) for shoulder pain with disability, and 1.08 ( 95% CI 1.04 to 1.13) for shoulder pain without disability. The outcomes were not related to duration of employment in one of the three trades. Conclusions: Quantitative exposure-response relations were established between current work with highly elevated arms and clinically verified shoulder disorders. Substantial long term cumulative effects were not shown. A potential for primary prevention was revealed.
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| 24. |
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| 25. |
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| 26. |
- Tommerup, Henrik, et al.
(författare)
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Existing sustainable renovation concepts, Deliverable D1.1 : Successful Sustainable Renovation Business for Single-Family Houses - SuccessFamilies
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Nordic single-family house renovation market is dominated by a craftsman based approach with individual solutions, traditional warehouses ”do-it-yourself-shops” and some actors marketing single products. To speed up the implementation of sustainable renovation of single-family houses there is a great need for full-service packages including consulting, contract work, follow-up, financing and operation and maintenance. There are few Nordic examples of such service models for renovation of single-family houses which entered the market recently. The success of these concepts is yet to be evaluated.One successful full-service package described in the report is a campaign by an energy company in Sweden who convinced 78% of 456 owners of houses with resistance heaters to connect to its biomass based district heating network. The campaign was successful because of its package offer and information provision with emphasis on economic aspects and functional reliability.The existing technical renovation concepts, typically focussing on application of only a few of the available technical solutions, have not been successful in realizing large scale energy efficiency gains. Renovation of single-family houses might be carried out based on design solutions with good combinations of the possible range of technical solutions including e.g. “passive (insulation) measures” and “solar measures” in order to reach a low primary energy level. Key aspects of reaching a low primary energy level in connection with renovation are described in the form of typical energy renovation measures and technical principles of low energy renovation including recommended extent of measures.Full service and technical renovation concepts should make it easy, simple and secure for the consumer to invest in a low energy renovation of their house. The building sector needs easy to use knowledge and initiatives which ensures that they can offer solutions which fulfil the demand for quality, economy and a simple process. To speed up the implementation of sustainable renovation of single-family houses, society needs to stimulate the process including better incentives structures, e.g. increased tax on energy and/or subsidy programmes. Combined with an outlook for rising global energy prices, sustainable renovation of single-family houses then has the potential to become an important market area in the future.
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| 27. |
- Vanhoutteghem, Lies, et al.
(författare)
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Sustainable renovation concepts for single-family houses, Deliverable D1.3 of the project Successful Sustainable Renovation Business for Single-Family Houses - SuccessFamilies.
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Due to the introduction of low energy standards for new houses as minimum requirements, rising energy prices and generally more focus on energy performance, there is a need for farreaching energy efficiency improvements in connection with renovation if existing singlefamily houses in the Nordic countries are to have competitive power compared to new houses on the future housing market. If the market is able to explain this to the homeowners there is an open market with undreamt-of possibilities. Good technical solutions exist but need to be combined based on the full range of (standard) solutions in order to reach the low primary energy level of new houses. The typical single-family houses identified to have large primary energy saving potential almost descend from the same time period in each Nordic country. The first segment is houses built in large numbers in the 1960 and 1970 before tightening of the insulation standards in the building codes in the late 1970’s due to the oil crisis. The second segment is houses built before 1945 (except for Finland) where a large part of them has been renovated, but energy renovation of those houses today would still account for a large energy saving. The third segment is type houses from the post-war period in Finland. A complete energy efficient renovation of a typical house include post-insulation and sealing of the buildings envelope - roof/ceiling, façade, windows/doors and foundation and maybe slab on ground - installation of a mechanical ventilation system with high efficiency heat recovery and low electricity use and if not already there, an energy efficient heating system based on district heating, heat pump etc. This package of technical solutions can be carried out during an overall or step wise planned renovation dependent on the condition of the house, the financial possibilities of the homeowner etc. Calculation of packages of energy efficient renovation solutions targeted the three segments of houses show that primary energy use and heating bill can be reduced with up to about 75% or a factor 4 corresponding to the level of a new house or better. It seems that the passive house level can not quite be reached with standard solutions. They require that more ambitious measures are applied. The total investment needed to reduce the heating bill by a factor 4 including replacement of e.g. roof and windows is up to EUR 100,000. It is generally difficult to obtain an economy in balance in the sense that the annual payment on a cheap loan, e.g. mortgage refinancing, to finance the investment is not fully offset by the expected annual energy savings. Since, the cost of energy measures today may not correspond to the increased market value of the house, it is important to find mechanisms so that the total cost of the energy investments in the future is reflected as an increased value of the house. But with due regard to all the non-energy benefits, such as better and healthier indoor environment and comfort, and less dependence on expected future higher energy prices, energy efficient renovation will probably still be attractive for the average homeowner. One-stop-shops in the form of full-service providers of energy efficient renovation of singlefamily house are missing in the Nordic countries. This service is vital to open up the market. A one-stop-shop could be seen as a possibility to make it easy for the homeowner to comply with possible future requirements to realize far-reaching energy savings in connection with extensive renovations, provided that the building sector offers the solutions. Homeowners need someone to take care of all relevant steps necessary for the renovation of the house including quotation for the work, financing and management of the contract work. An ideal full-service concept in five phases is proposed, going from initial evaluation of the house, to extensive analyses, proposal for package solutions, coordinated execution and operation and finally management of the house after renovation.
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| 28. |
- Werner, Anna, 1971-
(författare)
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External Water Condensation and Angular Solar Absorptance : Theoretical Analysis and Practical Experience of Modern Windows
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Part I of this thesis is a theoretical background to parts II and III. Part II treats the phenomenon of decreased visibility through a glazing due to external water condensation, dew, on the external surface. Some simulations are presented where it is shown that under certain circumstances condensation can be expected. A combination of coatings on the external surface is suggested to overcome the problem of external condesation. It consists of both a coating which decreases the emissivity of the surface and a hydrophilic coating which reduces the detrimental effects to the view through the window. Fresnel calculations of the optical properties are used to discuss the feasibility of using different coatings. A new test box was used to verify that the proposed window coatings perform as expected. Part III is a study on the angular dependence of solar absorptance in windows. Optical properties vary with the angle of incidence of the incoming light. The variation is different from one window pane to another. A model is proposed to approximate the angular variation of the solar absorptance in window panes. The model is semi-empirical and involves dividing the wide range of windows into nine groups. To which group a window belongs, depends on how many panes it has and on the features of the outer pane. The strength of the model is that it can be used without knowing the exact optical properties of each pane of the window. This makes it useful in the many cases when these data are not given by the manufacturer and Fresnel calculations to get the optical properties of the window are not feasible. The model is simple and can be added as an appendix to existing standards for measuring optical properties of windows.
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