This thesis has been carried out on behalf of IV Produkt AB and intends to set an average ratio of thermal energy losses in apartment buildings that were built during the 1960-1990. This shall be derived by analyzing the total district energy consumption that has been divided into three parts: heat energy losses (the actual heating requirements), the heating of domestic hot water and heating energy consumption for the controlled ventilation. Three different residential areas that were built during the years 1962-1966 and one that was built in 1993 has been analyzed. All residential areas are located in Växjö urban and contains between four and six apartment buildings. The analyzed objects have a mechanical exhaust ventilation systems and district heating as the heating method. No own laboratory work or experiments have been done in this thesis, the calculations have been done on the basis of parameters from VEAB, interviews with property managers, and literature studies. By calculations, we have got a result that is reported in Chapter 6. The result is given as a thermal energy loss as a percentage of the total heat consumption. In this thesis there has also been a review of the rules on requirements for the specific energy consumptions in buildings, indoor environment and indoor temperature from the National Board of Housing and the National Board of Health and Welfare.

Along with the increasing use of intermittent electricity sources, such as wind and sun, comes a growing demand for user flexibility. This has paved the way for a new market of services that provide electricity customers with energy saving solutions. These include a variety of techniques ranging from sophisticated control of the customers’ home equipment to information on how to adjust their consumption behavior in order to save energy. This master thesis work contributes further to this field by investigating an additional incentive; predictions of future energy savings related to indoor temperature. Five different machine learning models have been tuned and used to predict monthly heating energy consumption for a given set of homes. The model tuning process and performance evaluation were performed using 10-fold cross validation. The best performing model was then used to predict how much heating energy each individual household could save by decreasing their indoor temperature by 1°C during the heating season. The highest prediction accuracy (of about 78%) is achieved with support vector regression (SVR), closely followed by neural networks (NN). The simpler regression models that have been implemented are, however, not far behind. According to the SVR model, the average household is expected to lower their heating energy consumption by approximately 3% if the indoor temperature is decreased by 1°C.

The diploma thesis deals with energy assessment and proof of energy performance of the building when replacing the heat source in a family house. The theoretical part deals with thermography and thermocamera in energy practice. The experimental part of the thesis was focused on the thermographic survey of the object and the evaluation of the outputs. The computational part focuses on the energy analysis of the assessed energy economy.

The theme of the diploma thesis is study the influence of structural systems for the energy performance of buildings. The thesis compares designed and measured values of the energy consumption of selected buildings with different bearing structure materials beside the results from numerical modeling of energy consumption.

The residential building sector plays an important role in combating climate change in Canada. Many energy efficiency solutions along with new building energy standards have been implemented to improve building energy performance. However, their effects on energy saving and GHG emissions reduction vary due to the complexity of the building systems and the variability of their operational conditions. This work quantifies such variability in both energy efficiency devices and building energy standards implementation, respectively. The first study in this dissertation assesses the energy savings from sensible heat recovery in a residential apartment suite in various locations across Canada. A series of detailed building energy performance models are developed in TRNSYS. The HVAC system’s annual energy consumption is simulated and the results are compared with and without HRV for each climate zone. The results show the heating energy savings of employing the HRV vary from 17 to 34% depending on the winter climatic conditions; while, the building cooling energy use can be increased due to the undesired thermal recovery occurring in the HRV during the cooling season. The second study investigates the free cooling potential of outside air in various Canadian cities. A series of thermal models developed using BEopt 2.8 for a hypothetical single-family house with various window-to-wall ratios and building aspect ratios simulates hourly building cooling load profiles. The free cooling potential is analyzed by comparing the maximum available and the actual usable free cooling for various building features and different climates. The results indicate that, although free cooling is widely available in most areas of Canada during the summer and shoulder seasons, only 17-42% of such free cooling is usable without the use of thermal storage. The last study examines the effects of two building energy standards - the BC Step Code and the Passive House criteria - on reductions in residential household space heating GHG emissions under different enforcement scenarios. The space heating energy and the GHG emissions are estimated using the forecast growth of single detached households for the period from 2020 to 2032. The results show that the space heating GHG emissions can be reduced by 77% and 89%, respectively if the BC Step Code or the Passive House criteria is implemented in Canada. It is also found the impacts of energy code on GHG emission mitigation are less significant in regions where the carbon intensity of the dominant heating fuels is low. / Graduate

Detta examensarbete gjordes i samarbete med Riksbyggen där träffsäkerheten hos energiberäkningar i Miljöbyggnad studerades. Beräkningarna för den kommande energianvändningen jämfördes med mätningarna när byggnaden är i bruk. Vi ställde oss frågan om betygen i Miljöbyggnad påverkades av en avvikande energianvändning.Syftet med studien var att ge en bredare kunskap om miljöcertifierade byggnaders verkliga och förväntade energianvändning. Detta gjordes genom att identifiera och statistiskt säkerställa differenser mellan beräknad och uppmätt uppvärmnings-, varmvattens- och fastighetsenergi. Metoden som användes var en kartläggning av sekundärdata ur dokumentation från certifieringsprocessen för 116 stycken byggnader. Avvikande indikatorbetygs påverkan på områdes- och byggnadsbetyget i Miljöbyggnad undersöktes.Studien visade att det är svårt att beräkna - hälften av objekten hade en differens på mer än 10% och den årliga energianvändningen ökade i genomsnitt med 3,7 kWh/m2. Störst avvikelse hade uppvärmningsenergin med 9,7 kWh/m2, med sänkta indikatorbetyg till följd. En fjärdedel av dessa hade en vanskligt liten marginal till betygsgränsen.38% av flerbostadshusen hade ett förändrat betyg hos indikatorn för energianvändning, varav 4% fick ett bättre betyg medan 34% fick ett sämre betyg. En tredjedel av de med försämrade betyg fick sänkta områdesbetyg för energi, men behöll trots det byggnadsbetyget i Miljöbyggnad. Lagstiftande krav på minskad energianvändning fick delvis önskad effekt, samtidigt som differensen mellan beräkning och mätning ökade. Revideringar av indikatorbetyg tyder på att installationssystemen för ventilation och uppvärmningsenergin inte var korrekt intrimmade och behöver följas upp. I vilken omfattning man avsiktligt eller oavsiktligt frångått de ursprungliga planerna under byggprocessen lämnas till mer djupgående studier att ta reda på. / This thesis was created with collaboration from Riksbyggen where the accuracy of energy calculations in Miljöbyggnad were studied. Calculations for the upcoming energy use was compared with measurements of the energy of the building when in use. We asked ourselves whether the grades in Miljöbyggnad were affected by a deviating energy use.The purpose of this thesis was to provide a wider knowledge of the actual and expected energy use of buildings with an environmental certificate. This was achieved by identifying and statistically ensuring differences between calculated and measured energy of heating, hot water and real estate use. The method used was a survey of secondary data from the documentation of the process of certification of 116 buildings. The impact of a deviating indicator rating on the field and building rating in Miljöbyggnad was investigated.The study showed that it is difficult to calculate – half of the buildings had a difference of more than 10% and the annual energy use increased by an average of 3,7 kWh/m2.The most significant deviation was the energy used for heating with 9,7 kWh/m2, with decreasing indicator ratings as a result. A quarter of these had a precariously small margin to the limit of the rating level.38% of the residential buildings had a changed rating of the indicator of energy use, whereof 4% got a higher rating and 34% got a lower rating. A third of the ones with lower ratings also got decreased ratings in the field of “Energi”, but nevertheless retained their overall building rating in Miljöbyggnad.Legislative requirements for reduced energy use partly had the desired effect, though at the same time, the differences between calculations and measurements increased. Revisions of indicator ratings suggests that installation systems of ventilation and heating were not properly tuned and needs to be adjusted. To which extent they intentionally or unintentionally abandoned the original plan during the construction process is left to more thorough studies to look into.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management