This dissertation thesis primarily focuses on the experimental measurement of energy consumption of a given energy-passive family house as well as theoretical research in the field of energy calculations using computer simulations. The results of quasi-stationary and dynamic simulations, with varying computational and real-time climate data, are compared with experimental measurements. Using the dynamic calculation model, which was validated by actually measured data, the relationship between architectural design and the energy performance of the building was analyzed. The influence of selected different operating modes for heat consumption on heating, cooling, ventilation, and interior overheating is observed. The result of the mutual interaction of several input parameters of variant solutions provides the basis for optimization of the whole design.

The Directive 2002/91/EC of the European Parliament and Council on energy performance of buildings entered into force on 4th January 2003, setting the minimum requirements of energy performance. All Member States had to incorporate the requirements of the new directive in national legislation by January 2006 and build up relevant systems and measures to transpose and implement these requirements. The stage of Directive’s implementation in the countries of Southern Europe is reported because of the similar climatic conditions and the geographical location for a future enforcement in Greece, as the building code in Greece is still under development. As energy use in buildings accounts for about 40% of the final energy demand in the European Union, the application of building standards can achieve a reduction in electric energy consumption and therefore an increase in energy performance of buildings. A record of the electric energy consumption of office buildings in the four Prefectures of Crete is implemented aiming at a future energy saving, which may be obtained by either through increased efficiency or by reducing electric energy consumption.

The successful delivery of low-carbon housing (both new and retrofitted) is a key aspect of the UK s commitment to an 80% reduction in carbon emissions by 2050. In this context, the inclusion of small-scale building-integrated renewable energy technologies is an important component of low carbon design strategies, and is subject to numerous regulation and incentive schemes (including the Renewable Heat Incentive (RHI)) set up by government to encourage uptake and set minimum performance benchmarks. Unfortunately there are numerous examples of in-use energy and carbon performance shortfalls for new and retrofitted buildings this is termed the performance gap . Technical and human factors associated with building subsystem performance, which are often not considered in design tools used to predict performance, are the root cause of performance uncertainty. The research presented in this doctoral thesis aims to develop and apply a novel probabilistic method of evaluating the performance uncertainty of solar thermal systems installed in the UK. Analysis of measured data from a group of low carbon retrofitted dwellings revealed that the majority of buildings failed to meet the designed-for carbon emissions target with an average percentage difference of 60%. An in-depth case study technical evaluation of one of these dwellings showed significant dysfunction associated with the combined ASHP/solar thermal heating system, resulting in a performance gap of 94%, illustrating that the performance gap can be regarded as a whole-system problem, comprising a number of subsystem causal factors. Using a detailed dataset obtained from the UK s largest field trial of domestic solar thermal systems, a cross-cutting evaluation of predicted vs. measured performance similarly revealed a discrepancy with a mean percentage difference in predicted and measured annual yield of -24%. Having defined the nature and extent of underperformance for solar thermal technology in the UK, causal factors influencing performance were mapped and the associated uncertainty quantified using a novel knowledge-based Bayesian network (BN). In addition, the BN approach along with Monte Carlo sampling was applied to the well-established BREDEM model in order to quantify performance uncertainty of solar thermal systems by producing distributions of annual yield. As such, the modified BN-based BREDEM model represents a significant improvement in the prediction of performance of small-scale renewable energy technologies. Finally, financial analysis applied to the probabilistic predictions of annual yield revealed that the current UK RHI scheme is unlikely to result in positive returns on investment for solar thermal systems unless the duration of the payments is extended or electricity is the primary source of heating.

With the increased energy usage and its affect on the environment the European Union (EU) has issued climate and environment goals which will oversee countries energy saving potential. These goals focus on several areas including the energy usage within buildings. The purpose of this thesis is to categorize and analyze the energy saving potential for buildings constructed 1945 or earlier. The building stock in focus consists of 73 apartment buildings in Vasastaden, Linköping. The buildings were all chosen with Boverket’s database within building characteristics GRIPEN. The method consisted of stocktaking via location visits, categorizing and performing simulations on the buildings. The fictive buildings were based on the categorized building stock. They were modelled and simulated with the help of IDA Indoor Climate and Energy (IDA ICE). With the results of the energy usage a greater understanding of energy saving potential was obtained. The result of the categorization displayed that typical buildings in Vasastaden are buildings out of brick, fully detached (no adjoining walls), specifically with 3 floors. The fictive buildings have an calculated energy usage of 102-144 kWh/m2,year and have an energy saving potential within ranges of 17-41% compared to the building regulations set by Boverket (BBR). The building stock obtained an calculated energy usage of 804-3 515 MWh/m2,year. GRIPEN displayed several inaccuracies compared with the collected data from the location visits which proves that more frequent updates in databases such as GRIPEN are of high significance.

In Sweden, as well as in Europe, buildings are estimated to consume 40 % of the total energyuse. Moreover, one third of the European building stock consists of buildings with some sort ofdistinguable cultural or historic significance, and it follows logically that a considerablepercentage of Sweden’s and Europe’s total energy is consumed by this category of buildings –historic buildings. Especially when considering that historic buildings typically have inferiorenergy performance than other buildings. The challenge to improve the energy performance inhistoric buildings while also taking heritage values into consideration is undertaken within thescope of this master’s thesis. The European standard “Conservation of cultural heritage –Guidelines for improving the energy performance of historic buildings” (SS-EN 16883:2017) ispartially applied to a case-building in order to approach the challenge methodically.The energy performance of a building and proposed refurbishment measures is evaluatedthrough the use of computer-generated building energy models. Three different scenarios withsets of refurbishment measures have been simulated; (1) light impact, (2) moderate impact and(3) heavy impact on heritage values. Categorization of the refurbishment measures have beenaccomplished by using an objectivistic approach based on contemporary conservation theoriesand definitions. The theoretical framework is primarily based on conservation practices laid outby the Burra Charter.The light refurbishment package would reduce the heating energy use by almost 11 % whilehaving little to no impact on the building’s heritage values. The moderate package would reducethe heating energy use by 34,5 % without having a major impact on the building’s heritagevalues. The most invasive refurbishment package would, the heavy refurbishment package,would reduce the heating energy use by almost 40 %. This significant energy use reductionwould not come without its drawbacks. This package of measures would infact alter some of theexpressed character defining elements of the building.Improving the energy efficiency of built heritage is a challenge, especially when trying toassess the impact it might have on its heritage values. This master’s thesis can provide someinsight into the act of balancing energy improvement measures and cultural heritage valuesagainst one another, especially for buildings that lack formal protection in the form of legislativedirectives or policies. / I Sverige, såsom i övriga Europa, uppskattas byggnader stå för 40 % av den totalaenergianvändningen. En tredjedel av europeiska byggnader har någon form av kulturell ellerhistorisk betydelse. Detta tyder på att en betydelsefull andel av Sveriges och Europas totala energiförbrukas av denna kategori byggnader – historiska byggnader. I synnerhet när hänsyn tas till atthistoriska byggnader i allmänhet påvisar sämre energiprestanda än andra byggnader. Utmaningenatt förbättra energiprestandan i historiska byggnader samtidigt som man respekterar och beaktarkulturvärden behandlas inom ramen för detta examensarbete. Den europeiska standarden"Bevarande av kulturarv - Riktlinjer för förbättring av energiprestandan i historiska byggnader"(SS-EN 16883: 2017) tillämpas delvis på en byggnad för att på ett metodiskt tillvägagångssättangripa utmaningen.Byggnadens energiprestanda och föreslagna renoveringsåtgärder utvärderas genomanvändning och analys av datorgenererade energimodeller. Tre scenarier, bestående av olikarenoveringsåtgärder med varierande påverkan av kulturvärdena har simulerats; (1) lätt påverkan,(2) måttlig påverkan och (3) stor påverkan av kulturvärden. Kategoriseringen avrenoveringsåtgärderna har uppnåtts genom att använda ett objektivistiskt tillvägagångssätt baseratpå rådande definitioner och kunskap från byggnadsmiljövården. Den teoretiska referensramen ärhuvudsakligen baserad på bevarandepraxis som fastställts i Burra-stadgan.Renoveringspaketet med ”lätt påverkan” skulle minska användningen av värmeenergi mednästintill 11 % samtidigt som åtgärden har liten eller ingen betydande inverkan på byggnadenskulturvärden. Det ”måttliga paketet” skulle kunna minska användningen av värmeenergi med34,5 % utan att ha en alltför stor inverkan på byggnadens kulturvärden. Det mest omfattanderenoveringspaketet som innebär ”stor påverkan” skulle kunna minska användningen avvärmeenergi med nästan 40 %. Denna betydande förbättring kommer inte utan tillhörandenackdelar. Detta paket av åtgärder kan potentiellt skada eller förändra karaktären hos byggnaden.Karaktärsdrag som uttryckligen bedömts vara värda att bevara.Att förbättra energieffektiviteten hos kulturhistorisk bebyggelse är en utmaning, särskilt närman försöker bedöma vilken påverkan eventuella åtgärder kan ha på ovärderliga kulturvärden.Detta examensarbete kan ge viss insikt i hur man kan balansera energibesparingsåtgärder ochkulturvärden mot varandra, särskilt för byggnader som saknar särskilt uttryckta skyddsåtgärder iform av byggnadsminnesförklaring, lagstiftning eller politiska ställningstaganden.

This Engineering Doctorate aims to understand the factors that generate variability in small power consumption in commercial office buildings in order to generate more representative, building specific estimates of energy consumption. Current energy modelling practices in England are heavily focussed on simplified calculations for compliance with Building Regulations, which exclude numerous sources of energy use such as small power. When considered, estimates of small power consumption are often based on historic benchmarks, which fail to capture the significant variability of this end-use, as well as the dynamic nature of office environments. Six interrelated studies are presented in this thesis resulting in three contributions to existing theory and practice. The first contribution consists of new monitored data of energy consumption and power demand profiles for individual small power equipment in use in contemporary office buildings. These were used to inform a critical review of existing benchmarks widely used by designers in the UK. In addition, monthly and annual small power consumption data for different tenants occupying similar buildings demonstrated variations of up to 73%. The second contribution consists of a cross-disciplinary investigation into the factors influencing small power consumption. A study based on the Theory of Planned Behaviour demonstrated that perceived behavioural control may account for 17% of the variation in electricity use by different tenants. A subsequent monitoring study at the equipment level identified that user attitudes and actions may have a greater impact on variations in energy consumption than job requirements or computer specification alone. The third contribution consists of two predictive models for estimating small power demand and energy consumption in office buildings. Outputs from both models were validated and demonstrated a good correlation between predictions and monitored data. This research also led to the development and publication of industry guidance on how to stimate operational energy use at the design stage.

This thesis analyses a specific type of energy usage system, “energy usage in hotels”, and how this system behaves. In order to evaluate the current state of energy use in hotels, an energy audit questionnaire was developed and conducted among 31,5% of hotels on the Adriatic coast. The energy audit was used as a tool to set a benchmark for energy consumption in hotels and to identify opportunities for increased energy efficiency measures in HVAC systems. The analysis has shown that the average energy consumption in hotels on the Adriatic coast is in the range of 159 to 180 kWh/m2 and 162 to 225 kWh/m2 for seasonal and non seasonal hotels respectively. In order to establish a relationship between different independent variables in the hotels (total floor area and number of rooms) and dependent variables, such as electricity and oil consumption, mathematical statistical methods, such as correlation and regression analysis, were implemented. The objective of this thesis was also to develop - from an energy, environmental and economical points of view - a methodology for the design and retrofit of HVAC systems in the hotels on the Adriatic coast. The methodology named HOTECO is based on a system thinking approach. With respect to the technological aspects, the first step was to analyse conventional HVAC system designs and to compare it with the three most promising alternative HVAC systems utilizing renewable energy sources for a typical hotel. Computer modelling in TRNSYS was used to assess energy consumption. TRNSYS software has been used for simulations for a number of years, is internationally recognized, and has been validated and verified. It was concluded that energy and environmental savings in hotels on the Adriatic coast could be achieved using readily available technologies. The HOTECO methodology also demonstrated a framework that supports decision making iv regarding system selection and operational strategies to limit environmental impact from HVAC systems in hotels. Four scenarios for energy consumption in hotels on the Adriatic coast with regards to current state of energy systems and improved retrofit solutions utilizing renewable energy source were given. / QC 20100929

Efficient storage and retrieval of data is critical in today's computing environments and storage systems need to keep up with the pace of evolution of other system components like CPU, memory etc., for building an overall efficient system. With virtualization becoming pervasive in enterprise and cloud-based infrastructures, it becomes vital to build I/O systems that better account for the changes in scenario in virtualized systems. However, the evolution of storage systems have been limited significantly due to adherence to legacy interface standards between the operating system and storage subsystem. Even though storage systems have become more powerful in the recent times hosting large processors and memory, thin interface to file system leads to wastage of vital information contained in the storage system from being used by higher layers. Virtualization compounds this problem with addition of new indirection layers that makes underlying storage systems even more opaque to the operating system. This dissertation addresses the problem of inefficient use of disk information by identifying storage-level opportunities and developing pro-active techniques to storage management. We present a new class of storage systems called pro-active storage systems (PaSS), which in addition to being compatible with existing I/O interface, exerts a limit degree of control over the file system policies by leveraging it's internal information. In this dissertation, we present our PaSS framework that includes two new I/O interfaces called push and pull, both in the context of traditional systems and virtualized systems. We demonstrate the usefulness of our PaSS framework by a series of case studies that exploit the information available in underlying storage system layer, for overall improvement in IO performance. We also built a framework to evaluate performance and energy of modern storage systems by implementing a novel I/O trace replay tool and an analytical model for measuring performance and energy of complex storage systems. We believe that our PaSS framework and the suite of evaluation tools helps in better understanding of modern storage system behavior and thereby implement efficient policies in the higher layers for better performance, data reliability and energy efficiency by making use of the new interfaces in our framework.

Roughly 130 000 dwellings have been officially registered since Norway as of summer 2009 passed their bill “Energimerkeforskriften” on energy performance certificates in buildings. The main objective is to decrease the total amount of national energy consumption by producing a methodology of calculation of the integrated energy performance of buildings as well as proposing cost effective measures to lower each building’s energy consumption.  As the measures should not contravene nor be incompatible with the intended quality and character of the building, the “Energimerkeforskriften” exempts buildings that due to their historical and cultural values are protected cultural heritage legislation. The current system offers a couple of professional certification alternatives, but when two online semi-automatic methods developed specifically for non-professionals are by far the most used, and since the methods of calculation primarily have focused on modern building materials and construction, the rest of the historical building stock stands literally unprotected by incorrect performance certificates and high-risk energy efficient measures.  The objective of this thesis is to identify if the current Norwegian energy certificate system poses a threat to older buildings. It also tries to pinpoint relevant additions in order to minimize those potential risks in a near future by relating potential impact to what is determined as the main character-defining values of a building. The results show that the system clearly has its flaws, mainly regarding the estimation of energy consumption, and that the automatically recommended energy efficient measures would pose a serious potential threat to the historical building stock of Norway if they were to be implemented. / Bakgrunden till arbetet är de krav som EU direktivet (2002/91/EF) om byggnaders energiprestanda ställer på upprättande av energideklarationer och energieffektiviserande åtgärdsförslag. Till följd av att direktivet lämnat utrymme för given tillämpningsmetod har Norge utvecklat ett deklarationssystem där gemene hus- och fastighetsägare fått möjlighet att själva genomföra sin energideklaration, något som i andra länder enbart får genomföras av oberoende experter eller företag. Sedan systemet togs i bruk under slutet av 2009 har cirka 130 000 unika energideklarationer genomförts av privatpersoner genom den officiella hemsidan för Energimerke-systemet. Hemsidan tillhandahåller ett energiberäkningsprogram vilket med hjälp av olika tekniska och byggnadsrelaterade uppgifter som registreras av använder genererar en energideklaration. Systemets beräkning av byggnadens energibehov och uppvärmningssystemets verkningsgrad faller sedan samman i ett energimerke som i sin tur är ett krav att ha vid försäljning eller uthyrning av en bostad. Utöver själva beviset rekommenderas även ett antal energieffektiviserande åtgärder.  Med ett rådande undantag för kulturhistoriskt skyddade byggnader och ett system som inte är anpassat efter äldre konstruktioner verkar det dock kunna finnas vissa risker med den nuvarande metoden. För att genomföra en första granskning av systemet och dess möjliga konsekvenser för äldre byggnader i Norge har detta arbete därför ställt ett stort statistiskt underlag av tidigare energideklarationer mot utfallet i några fallstudier och simuleringar. Syftet är att ge svar på huruvida energideklarationssystemet utgör ett hot mot äldre byggnaders karaktärsbärande värden eller ej, samt försöka identifiera hur systemet kan förbättras och utvecklas. Ett viktigt moment i att försöka svara på arbetets frågeställningar har utgjorts av ett resonemang vilket lett fram till det sammanvägande begreppet karaktärsbärande värden. Satt i förhållande till energideklarationssystemets åtgärdsförslag och lagrummets egna varsamhetsparagrafer har det kunnat ge en fingervisning om vilka åtgärder som utgör störst risk för äldre byggnader.  Resultaten visar att systemet med estimerade energiberäkningar verkar genera felaktiga värden som förvärras ju äldre och enklare byggnaderna respektive registreringarna är. Det är även tydligt att åtgärder med hög risk för byggnaders karaktärsbärande värden ständigt återkommer som förslag samtidigt som systemet ej heller tar hänsyn till kostnadseffektiva aspekter. För att minimera riskerna föreslås att systemets tekniska ramar utvidgas samtidigt som systemets åtgärdsförslag ses över och eventuellt begränsas till att gälla brukarrelaterade råd. / Spara och Bevara

China is the world’s largest producer and consumer of household appliances, lighting and commercial equipment. China first adopted Minimum Energy Performance Standards (MEPS) in 1989. By 2013, China has developed and implemented 52 Energy Efficiency Standards (EES) and 28 mandatory energy labels for a wide range of domestic, commercial, and selected industrial equipment. However, despite of the large number of standards issued, big challenges remain with how to ensure the standards keep up with the dynamic evolvement of technologies and appliance market after they enter effect. The current policy analysis methods adopted by the policy makers primarily focuses on standards making process and very limited attentions were paid on impact assessment and ex-post evaluation of standards and labeling systems, hence the effectiveness of active Energy Efficiency Standards has not been assessed timely and comprehensively. One major barrier of this is the lacking of assessment methods and market data. This thesis intends to tackle the above issues by developing a new policy analysis approach that can be used to assess the impact of energy efficiency standards and labeling with market data. This approach adopts a comprehensive analysis method that comprises three components: (1) Analysis of market data; (2) Quantification of energy savings potential; and (3) Benchmarking China’s EE standards to those of peer economies around the world. This integrated approach leads to three independent but complementary studies that provide evidence-based findings and policy recommendations for the improvement of China’s appliance standards.