Syftet med projektet är att analysera avvikelser mellan beräknad och uppmätt energianvändning för ett antal flerbostadshus i Stockholm. Detta är ett ämne som har uppmärksammats av myndigheter och företag, samtidigt som att energikraven blir ständigt tuffare. Av Sveriges totala energitillförsel används cirka 40 procent för drift och uppvärmning av byggnader, vilket innebär att byggsektorn bör arbeta aktivt med att minska energianvändningen och spela en stor roll i omställningen mot klimatneutralitet år 2045 för Sverige. Målet med projektet är att identifiera bidragande faktorer till avvikelser mellan energiberäkning och energianvändning för utvalda projekt, samt att ta fram förslag på förbättringsåtgärder som bidrar till förbättrade energiberäkningar och minskad energibehov. Metoden som används är att först analysera storlek på objekten för att sedan analysera den totala avvikelsen för dessa objekt på årsbasis och månadsbasis. Den totala avvikelsen analyseras på årsbasis, sedan kartläggs den månatliga förbrukningen i fyra poster: fastighetsel, värme, tappvarmvatten och hushållsel. En ny simulering och energiberäkning utförs på ett utvalt projekt med fokus riktad på orsaker till avvikelser. Resultatet visar att den mest bidragande faktorn till avvikelser är högre VVC-förluster, högre inomhustemperatur under uppvärmningssäsongen, lägre internvärme och högre ventilationsflöde. Vidare visar studien att det är möjligt att hitta orsakerna till avvikelse genom att enbart undersöka mätdata, om det är bra mätningsunderlag. / The purpose of the project is to analyze deviations between calculated and measured energy consumption for several apartment buildings in Stockholm. This is a topic that has been brought to the attention of authorities and companies, while at the same time the energy requirements are becoming increasingly tough. About 40 percent of Sweden's total energy supply is used for operation and heating of buildings, which means that the construction sector needs to work actively to reduce energy consumption and play a major role in the change towards climate neutrality in 2045 for Sweden. The aim of the project is to identify contributing factors to deviations between energy calculation and energy consumption for selected projects, and to develop proposals for improvement measures that contribute to improved energy calculations and reduced energy consumption. The method used is to first analyze the size of the objects and then to analyze the total deviation of these objects on a yearly and monthly basis. The total deviation is analyzed on an annual basis, then the monthly consumption is mapped into four items: real estate electricity, heating, domestic hot water and household electricity. A new simulation and energy calculation are performed on a selected project with a focus on causes of deviations. The result shows that the most contributing factor to deviations is higher VVC losses, higher indoor temperature during the heating season, lower internal heat and higher ventilation flow. Furthermore, the study shows that it is possible to find the causes of deviation by examining measurement data only if there is good measurement basis.

As the world is becoming aware of the impact of global warming reducing greenhouse gases emissions presents itself as a fundamental issue in order to avoid the environmental collapse and its negative consequences. One of the key points of this challenge it’s to make a responsable use of the energy. In European countries, buildings sector consumes around the 40% of the total energy use. Thus ensuring energy efficiency becomes a vital issue in order to reduce energy usage and its environmental impact. This master thesis reports on the energy audit made in Din Hälsocentral. The energy use of the health center is studied through a heat energy balance from September to May (the months when the local district heating network works) with the aim of suggesting cost-effective energy saving measures.The study combines information provided by Din Hälsocentral, data estimated based on the characteristics of the installations and literature review. The energy balance shows that Din Hälsocentral has a heat energy input 595 MWh. This heat is received by the health center through district heating, solar radiation and internal heat generation while it’s lost through transmission losses, mechanical ventilation losses, infiltration heat losses and tap water heating. To decrease the energy use five saving measures have been suggested: the substitution of the health center windows by more efficient ones, the reduction of the indoor temperature, the replacement of the heat exchangers from the mechanical ventilation system, the installation of an aerothermal heating system in order to replace the district heating supply and the improvement of the roof isolation. The implementantion of those different measures would report heat energy savings between the 4% and the 63%, having payback periods between 0 and 7 years. However, the viability of application of aerothermal heating system in the health center installations as well as its maintenance costs must be studied more deeply.

In 2017, the Swedish Parliament voted for a climate aim which says Sweden should achieve zero net emissions of greenhouse gases in 2045. The building and construction sector is one of the sectors that needs to reduce it’s climate impact. As of 2016, 12.8 million tons of CO2-equivalents was estimated emitted from the sector, which represented about 21 percent oftotal amounts of GHG-gases emitted from Sweden in that year. Several studies has shown that the operational energy use in the life cycle of buildings is source to the majority of the emissions. This thesis was written in collaboration with Skanska Sweden, a Swedish construction company. Currently, there is no available value for the CO2-emissions emitted per m2 from the operational energy use in facilities and households at Skanska Sweden. The aim of this report is therefore to estimate the CO2-emissions emitted per m2 from various building types.This has been achieved through data investigations of what data is available and missing. Furthermore, methodologies have been investigated as well as energy sources for various buildings. Then the emissions were calculated as CO2-eq/m2 per building type. A sensitivity scenario was additionally performed by calcuating climate impact from different electric grids (Swedish, Nordic and European). Finally, a future energy scenario was investigated for2050 to estimate future climate impact from the operational energy use in various building types. The energy data was based on two different databases, Base and Follow Up, whereas Base presented estimated energy interval values. Follow Up presented estimated and verified values. In the data collection, a categorisation was made depending on the various building types Skanska Sweden produces. The 7 categories was Houses, Multi-dwelling buildings,Offices, Care centers, Schools, Pre-schools and Other. The findings were that in all categories but two (schools and offices), the operational energy use is higher when the values are verified, rather than estimated. Recommendations are therefore to increase the amount of available verified values, however, at the same time the amount of estimated values need to increase as well as many categories had a deficient amount of available data, this to increase the reliability of the results. The difference in calculated climate impact is relatively large between categories, depending on energy sources for heating and hot tap water. For instance is the climate impact lowest for Houses when the majority of the energy comes from electricity. At the same time, the climate impact from the category Other is highest, which is because the energy use is high, but additionally because the majority of the energy comes from district heating. Overall, this energy source has higher climate impact than when the electricity is used. Nevertheless, it should be observed that the difference in categories is overall huge, depending on the chosen electricity grid. Future emissions (2050) will be significantly lower than today, especially when the European grid and the EU reference scenario is chosen, but will be dependent on electricity prices additionally. However, if the Swedish climate aim of climate neutrality will be achieved, the climate impact from the operational energy will be minimal in 2050. An important aspect in environmental evaluations of energy is methodological choice. In this project, the attributional perspective has been chosen, however, many studies imply the importance of margin energy, which the attributional perspective does not include.Furthermore, the attributional may present a lower climate impact than when other methodologies are chosen. It is therefore important to be aware of the methodology used and recommendations for future studies would be to investigate the methods more thouroughly. / Under 2017 röstade svenska riksdagen igenom en klimatlag som begränsar klimatpåverkan till netto noll år 2045 från samtliga sektorer. Bygg- och fastighetssektorn är en sektor medstor klimatpåverkan och utgjorde år 2016 21 procent (12.8 miljoner ton) av totala utsläpp i Sverige. Historiskt sett har energianvändningen i drift av byggnader utgjort majoriteten av utsläppen från bygg- och fastighetssektorn och är därför en viktig del att utforska. Skanska Sverige är ett svenskt byggföretag och detta arbete har gjorts i samarbete med företaget. För tillfället finns inget värde på CO2-utsläppen kopplade till energin i drift av byggnader (hushåll och lokaler) som byggts av Skanska Sverige och målet med denna rapport är därför att estimera CO2-utsläpp/m2 från olika byggnadstyper. Detta har upnåtts genom att bland annat utforska vilken data som finns tillgänglig och vad som saknats, samt att utforska metodval och energikällor för olika byggnader för att sedan omvandla energidatan til lgenererade CO2-utsläpp/m2. Vidare utfördes en känslighetsanalys genom att beräkna CO2/m2 för olika elnät (svenskt, nordiskt och europeiskt). Slutligen har även ett framtida energiscenario beräknat för år 2050 använts för att beräkna klimatutsläpp från driftenergin iframtiden. Datan är baserad på två olika databaser, Base och Follow Up, där Base har endast redovisat estimerade energivärden som anges som intervall av nio kWh, samtidigt har Follow Up redovisat både estimerade och verifierade värden. På grund av större datatillgänglighet i Base valdes denna att huvudsakligen basera beräkningar på, men Follow Up och dess verifierade värden har använts till jämförelse. En kategorisering gjordes beroende av vilka byggnadstyper Skanska producerar mest av. De 7 kategorierna var småhus (villor och radhus), flerfamiljshus (lägenheter), kontor, sjukhem, förskolor, skolor och övrigt som inkluderade bland annat sjukhus och hotell. Resultaten har visat att i alla kategorier utom två (skolor och kontor) är energianvändning högre när energin är verifierad än när den är estimerad. Rekommendationer är därför att öka antalet verifierade värden som samlas in, samtidigt som de estimerade även behöver öka för att öka pålitligheten av resultaten då många kategorier har begränsad mängd indata. Skillnaden i beräknad klimatpåverkan är relativt stor mellan olika kategorier, beroende av energikällor för värme och varmvatten. Exempelvis är klimatpåverkan lägst för småhus då största andelen energitillförsel för småhus utgörs av elektricitet. Samtidigt är klimatpåverkan hög från kategori Other, vilket till stor del beror på att energianvändningen (kWh/m2) är hög, men även på grund av att majoriteten av energitillförseln kommer från fjärrvärme. Generellt sett har denna energikälla högre klimatpåverkan. Dock skall det observeras att skillnaden inom kategorier även den är stor, beroende av vilket elnät som valts. Exempelvis är skillnaden stor mellan småhus där elnätet som använts är svenskt, och när elnätet varit europeiskt. Framtida utsläpp kommer vara betydligt lägre än idag, speciellt när det europeiska nätet väljs och EUs referensscenario är utforskat, men är även beroende av framtida elpriser och satsningar på förnybart. Ska det svenska målet om klimatneutralitet 2045 dock uppfyllas kommer klimatpåverkan vara minimal år 2050. En viktig aspekt vid miljövärdering av energi är metodval. I detta projekt har bokföringsperspektivet använts, men flertalet studier har påpekat vikten av att inkludera marginalenergi, samt visat att perspektivet ofta redovisar lägre klimatpåverkan än till exempel konsekvensperspektivet. Det är därför viktigt att vara medveten om vilken metodik som väljs och framtida rekommendationer för studier är förslagsvis att utforska flera metoder,gärna parallellt för att se skillnader.

Although U.S. commercial catfish aquaculture ponds are in temperate regions and experience cool to cold temperatures during the winter, few studies have investigated the effects of low temperatures on catfish physiological processes. Therefore, growth, metabolism, swimming performance, and blood variables were compared between channel (Ictalurus punctatus), blue (I. furcatus), and hybrid (I. furcatus x I. punctatus) catfish at 10 and 20°C. Accelerometers were also used to evaluate relationships among acceleration, metabolism, and tail beat frequency (TBF) during swimming performance tests. Channel catfish experienced the greatest growth, yet growth was diminished across all fish types at 10°C. Metabolic processes, swimming performance, and related blood variables were also diminished at 10°C. Relationships among acceleration, metabolism, and TBF were found indicating cold temperatures inhibit maximum production in catfish and provide initial steps for creating holistic bioenergetic models for further application.

The primary energy costs of building materials and structures are discussed and comparisons are made between typical dwelling types. The economics of alternative wall, roof and floor constructions, providing various levels of insulationy are examined. Costs are assessed for a number of periods from 1970 to early 1980 for heating by gas and night rate electricity. The effect of price changes-on the economic attractiveness of insulation is investigated and the likely effects of future price rises are considered. It is concluded that, in certain circumstances, higher levels of insulation than those normally used in the UK have been economically attractive for the last few years and may possibly become more so. A survey of over fifty local authority houses with central heating, carried out by the author in Spring 1978, is described. Three types of houses of similar size were involved, having gas-fired 'wet' systems, and ducted warm air heating from electric storage and gas-fired units respectively. The survey was designed to determine certain aspects of occupant behaviour relevant to fuel consumption. Using regression techniques, relationships are obtained which explain more than two thirds of the variance of mean useful energy input rate between the houses of a given type in cold weather in terms of hours of use of central heating window opening habits, and for warm air heating, the closing of outlet registers. It was also revealed that for the house types with gas-fired heating the number of hours of use of the central heating was strongly influenced by household size and occupancy patterns. The implications for building design of the effects of occupant behaviour and of financial and energy costs are discussed.

The standard design approach of water distribution systems requires that pressure at any point in the system is maintained within a range whereby the maximum pressure is not exceeded so that the likelihood of a pipe burst is reduced and the minimum pressure is always maintained or exceeded to ensure adequate flows for satisfying expected demands. High pressure systems tend to cause more frequent pipe breaks and an increase in energy use and leakage. Low pressure systems cause consumer complaints, make the system more susceptible to negative pressures, and possibly to the ingress of contaminants during transient events. The overall goal of establishing pressure standards is to balance these opposing tendencies to achieve a safe, reliable, and economic operation of the system. Yet, there are no universally acceptable or established rules or guidelines for establishing a pressure standard for water distribution system design, and few studies have considered whether the traditional standards are still applicable in modern systems. This study has made a critical appraisal on what pressure standards mean, where they are violated, and where they need revision to achieve a comprehensive picture about what the pressure standards really mean. The research also highlights the inter-related issues associated with pressure criteria. Assessment of the relationships governing water pressure, leakage, energy use and economics is realized via the analytical investigation of single pipes and the simulation of representative networks using the steady state analysis software EPANET 2. The role of minimum pressure standards, storage, pumping strategy, and resource prices on the energy and water loss of systems is analysed and assessed. In anticipation that pressure contributes to pipe break rates, a probabilistic approach considering uncertain water demand and pipe’s roughness modeled with a Monte Carlo simulation (MCS) algorithm is presented. This study also explores how the minimum pressure standards affect transient pressures and reviews how destructive transient pressures may be controlled to limit reduced pressure surges within acceptable limits even when the minimum steady state pressure is relatively low. In order to place the research in practical context, this study develops a surge limit control algorithm for the design of a portable device for limiting the down-surge pressures by creating a pressure control boundary in a pipe system during hydrant operations. This boundary is established using the portable control device to safely operate a hydrant in a water distribution system. This study also highlights the notion that high level of pressure standards may lead to a troublesome squandering of water and energy and may disrupt the performance of water distribution systems. Given the too often degraded nature of water supply infrastructures, the on-going challenges of urban growth, and the increased stress on natural resources, the significant benefits of better controlling water pressure are not only welcome but urgently needed. / Thesis / Doctor of Philosophy (PhD)

Building energy models are used to forecast building energy use to design and control efficient building energy systems. Building energy use can generally be decomposed into heating, ventilation and air conditioning, refrigeration, appliance and lighting loads. These loads will depend on multiple factors such as outdoor weather conditions, occupants, building type, controls and scheduling. Data-driven models have become more popular with the increase in smart meter data available that can be used to train and fit the models. Additionally, buildings with high refrigeration loads have greater heat harvesting potential, however, few data-driven models have been developed for buildings such as supermarkets and ice rinks. In this work, linear regression models are used to predict the disaggregated space cooling, heating, baseload and refrigeration components of building energy use. In most cases, measured aggregate electricity use is available, however individual appliances or component loads require submetering equipment which can be expensive. Therefore the proposed models use time-based and weather features to separate the thermal and baseload portions of the electrical load. A generalized approach is also used to predict new buildings with data from existing buildings. Furthermore, a simplified model is used to predict hourly space heating from monthly natural gas measurements and hourly weather measurements. The models were evaluated on real data from buildings in Ontario and the disaggregated loads were verified with synthetic data. The results found that aggregate use was predicted reasonably well using linear regression methods, with most building types having a median normalized root mean squared error between 0.2 and 0.3, depending on the forecasting period. The model is flexible as it does not require detailed information related to the building such as lighting or setpoint schedules, however, it can be adapted in the future to include additional information and improve predictive capability. / Thesis / Master of Applied Science (MASc)

A manufacturer would love to see progress in the optimization of a production system to maximize profit while maintaining the environmental regulations enacted by a government or society. Thus, a key performance indicator is needed to indicate how the system production is performing in monetary as well as environmental aspects. However, the manufacturer and the regulating body may not be aware of the environmental impacts associated with the production system as a key performance indicator like Overall Equipment Effectiveness (OEE) only implies the monetary aspects of the process. Therefore, there is a need to quantify the carbon emissions of the process and use it as a parameter that indicates profitability and environmental sustainability at the same time. From the public and policy-making body's point of view, they need a proper scale that can be used to track the compliance of the manufacturers with the environmental regulations. In this study, this carbon-based indicator (COEE) aims to discover a way of monitoring the progress of a process with environmental considerations. This study raises key questions that are constructive to each other to build a comparison of the ordinary OEE and environmental COEE. To do so a case study about the plastic process using an injection molding machine is conducted. The data used in this study was provided by the company named Good Solutions. Based on the data provided, the ordinary OEE of the machine for each shift is used to contrast with the result of the new modeled COEE. The RMSE for the given OEE of the machine was 13.424 while for COEE is 12.695. The RMSE of both OEEs indicates that the COEE can be used as an indicator for economic as well as environmental assessments.

The main purpose of the study is to investigate if Boverkets supplement BEN is reasonable for apartment buildings with individual metering and charging for hot water. But also if there is any connection between hot water consumption, number of residents, bathtub and number of rooms in the apartments. Finally, it is investigated whether the residents make any active choice to reduce their consumption of hot water and if so why.In total, measurement data has been obtained from 2097 apartments distributed among 21 tenant-owned associations in Stockholm and Uppsala where Riksbyggen is the estate manager. The study also includes a comprehensive survey that was sent out to 975 apartments distributed among nine tenant-owned associations. The purpose of the survey is to get a better picture of how households reason about their hot water consumption. Through the database provided by Infometric, the work has had access to the apartments' actual hot water consumption. Thus, it has been possible to retrieve measurement data from all associations and to pair individual survey responses with the apartments' unique meter ID.The results presented in the study show that the associations are 27.1% below Boverkets supplement BEN for ordinary fixtures. At BEN for low-flush fixtures, the associations are 19.6% below the supplement. The study shows that factors such as the number of residents and the number of rooms and kitchens have a major impact on hot water consumption. Indications also show that bathtubs affect consumption to the negative to the extent that hot water consumption tends to increase. It also appears that residents are actively trying to minimize their hot water consumption where environmental reasons are stated as the main cause.

The design of a residential building to maximize comfort and energy savings is nowadays anchored in technical guidelines, although it is clear that individual preferences and subjective experiences play an undeniable role. Starting from this conflict, this study investigates the potential of new data sources (Internet of Things) and smart home technology as tools to better investigate and understand the real needs and preferences of individual inhabitants and, at the same time, to help the building adapt and respond to its occupants. In many countries, environmental energy monitoring systems for residential buildings remain unregulated and are not mandatory, a situation attributed to the high costs, perceived invasiveness, limited flexibility, and ambiguous benefits to the end-users; consequently, even in optimal scenarios, their application is confined primarily to building managers rather than the actual occupants. With smart homes, the ability to collect data and information has exploded, as the number of low-cost sensors now available on the market. This has also led to widespread automation, with the ability not only to monitor but also to "control" the built environment. Alongside these advancements, however, lies the risk of accumulating vast amounts of data that are unmanageable and useless, lacking tangible significance. Concerns over privacy and loss of control over one's private living space are raising, coupled with skepticism regarding the true efficacy of these systems. To truly optimize building performance, particularly within the residential sector, it is imperative to first gain an in-depth understanding of the intricate interplay between the built environment and its occupants, select the right aspect to optimize, and then provide the necessary information for optimization to stakeholders. Therefore, some questions arise: Is it possible, in the right situations, to use this less invasive and less expensive technology in place of more structured monitoring systems, the same ones also used in academic research? Is it a reliable technology? Can a monitoring system bring real benefits to the inhabitant and the building in terms of energy savings and quality of life improvement? Can it be adapted to the specific preferences and needs of both the building manager and the occupant? The present study begins by examining the concepts of indoor comfort and energy use in residential settings from a new perspective, incorporating a systematic literature review that delves into socio-cultural aspects. Adopting an interdisciplinary “learning by doing” approach, it deepens the topics of user-centered monitoring, the human-building interactions, and the wide-ranging resources and potential challenges that come with domestic environments. To concretely answer the theoretical and technical questions raised, the study paired its theoretical analysis with the design and prototyping from scratch of a plug-and-play, low-cost, and non-invasive monitoring and automation system called MOQA, which leverages smart home technologies. This process facilitated a comprehensive understanding of the data lifecycle  from its production and collection to its management, presentation to key stakeholders, and final evaluation by the end-users  essentially assessing its utility. The deployment of MOQA across different case studies, alongside its evaluation against more conventional monitoring systems, enabled an examination of the system’s acceptance, functionality, user interaction, stability, and overall performance. These experiences, despite some limitations, highlighted the user's pivotal role in effectively utilizing and truly benefiting from these systems. Support from individuals with in-depth knowledge of the system and its benefits is crucial, leading to satisfaction even among people who were initially skeptical. Over time, the system proved to be stable, accurate, accepted and, eventually, integrated into daily routines. Prioritizing hands-on solutions over theoretical debates about comfort and energy norms, the smart home system is perceived, in a personal parallel with the theory of salutogenesis in architecture, as a tool capable of connecting the inhabitant with the resources available in the building. Advancement in the spontaneous and beneficial exchange between humans and the environments they live in, spanning built and natural, leads to an uplift in the quality of life. Overall, the doctoral study contributed to exploring the potential of smart homes by merging the perspectives of research and users and broadening the strictly economic and business vision currently associated with the topic. Scientific, industrial, social, and environmental implications were addressed, suggesting future lines of research.