Buildings play a central role for livability and carbon footprint of urban areas. Ambitious energy saving and emission reduction targets created a need for a new generation of decisionsupport methods and tools that allow for detailed analysis of urban energy on a large scale. Urban building energy modeling (UBEM) that has emerged recently is an efficient approach to assess energy performance of multiple buildings and system effects from urban energy interventions. However, the further upscale of UBEMs is significantly limited due to the lack of automation for building energy performance (BEP) simulations required for such models in large amounts. This thesis aimed to explore challenges for automation of BEP simulations, and to develop a prototype tool that would serve as a middleware between UBEM and BEP simulation engine, focusing on the IDA ICE simulation software. The result of this thesis is icepy — a tool for automation of BEP simulations in IDA ICE. It uses IDA ICE API and Lisp scripting to provide interaction between UBEM process and IDA ICE in order to generate initial simulation model (IDM), execute simulation and manage results in an automated way. Being implemented as a Python package, it allows to modify multiple IDMs or export simulation results with a few lines of code. The developed tool has been tested and validated for the case building in Minneberg, Stockholm. The automation capabilities provided by icepy has allowed to perform sensitivity analysis for building design parameters as was demonstrated for the window-to-wall ratio (WWR) and three various algorithms for window distribution. The resulting tool has limited functionality as it addressed building envelopes which is only one component of building simulation. However, it has proved to be an efficient approach to automate simulation process and has shown a good potential for further development of such tools. / Byggnader spelar en central roll för urbana områdens levbarhet och koldioxidavtryck. Ambitiösa mål för energibesparing och utsläppsminskning har skapat ett behov av en ny generation beslutsstödmetoder och verktyg som möjliggör detaljerad analys av städers energianvändning i stor skala. Urban byggnadsenergimodellering (UBEM) har nyligen utvecklats och är ett effektivt tillvägagångssätt för att bedöma energiprestanda för flera byggnader och systemeffekter för olika energiåtgärder inom den urban miljön. Den ytterligare uppskalningen av UBEM är dock begränsad på grund av bristen på automation av simulering som är inriktade på byggnadsenergiprestanda (BEP), vilket krävs för att hantera stora byggnadsbestånd. Det här examensarbetet syftar till att utforska utmaningar med automatisering av BEP-simuleringar och att utveckla en prototyp som ska fungera som en mellanprogramvara mellan UBEM och BEP-simuleringsmotorer, med fokus på IDA ICE(som är en simuleringsprogramvara). Resultatet av examensarbetet är icepy, som är ett verktyg för att automatisera BEP-simuleringar i IDA-ICE. Icepy använder IDA ICE API och Lispskript för att tillhandahålla interaktion mellan UBEM-processen och IDA ICE för att generera en initial simuleringsmodell (IDM), utför själva simuleringen och slutligen hanterar resultatet på ett automatiserat sätt. Genom att icepy implementeras som ett Pythonpaket kan den modifiera flera IDM:er och även exportera simuleringsresultat med några få kodrader. Området Minneberg i Stockholm har använts i en fallstudie för att validera och testa verktyget. Automatiseringsfunktionerna i icepy har möjliggjort känslighetsanalyser för olika byggnadsdesignparametrar, exempelvis studerades påverkan av olika värden på förhållandet mellan fönster och väggar genom användning av tre olika algoritmer för fönsterdistributioner. Det utvecklade verktyget har begränsningar i funktionalitet framförallt på grund av att enbart byggnadens ytterskal studerades i byggnadsenergisimuleringarna. Verktyget har dock visat sig vara ett effektivt tillvägagångssätt för att automatisera simuleringsprocesser, vilket visar på en god potential att också vidareutveckla dessa verktyg.

This dissertation explores the idea of inducing grid peak demand curtailment by turning commercial buildings into interactive assets for building owners during the demand control period. The work presented here is useful for both ab initio design of new sites and for existing or retrofitted sites. An analytical hierarchy process (AHP)-based framework is developed to curtail the thermal load effectively across a group of commercial buildings. It gives an insight into the amount of peak demand reduction possible for each building, subject to indoor thermal comfort constraints as per ASHRAE standards. Furthermore, the detailed operation of buildings in communion with the electric grid is illustrated through case studies. This analysis forms an outline for the assessment of transactive energy opportunities for commercial buildings in distribution system operations and lays the foundation for a seamless building-to-grid integration framework. The contribution of this dissertation is fourfold – (a) an efficient method of developing high-fidelity physics-based building energy models for understanding the realistic operation of commercial buildings, (b) identification of minimal dataset to achieve a target accuracy for the building energy models (c) quantification of building peak demand reduction potential and corresponding energy savings across a stipulated range of thermostat setpoint temperatures and (d) AHP-based demand curtailment scheme. By careful modeling, it is shown that commercial building models developed using this methodology are both accurate and robust. As a result, the proposed approach can be extended to other commercial buildings of diverse characteristics, independent of the location. The methodology presented here takes a holistic approach towards building energy modeling by accounting for several building parameters and interactions between them. In addition, parametric analysis is done to identify a useful minimal dataset required to achieve a specified accuracy for the building energy models. This thesis describes the concept of commercial buildings as interactive assets in a transactive grid environment and the idea behind its working. / Doctor of Philosophy / This dissertation titled "An Expert-based Approach for Grid Peak Demand Curtailment using HVAC Thermostat Setpoint Interventions in Commercial Buildings" tackles two important challenges in the energy management domain: –electric grid peak demand curtailment and energy savings in commercial buildings. The distinguishing feature of the proposed solution lies in addressing these challenges solely through demand-side management (DSM) strategies, which include HVAC thermostat setpoint interventions and lighting control. We present a methodology for developing highly accurate building energy models that serve as digital twins of actual buildings. These digital replicas can be used to quantify the impact of various interventions and reflect the realistic operation of commercial buildings across varied conditions. This enables building owners to control demand intelligently and transact energy effectively in the electricity market. The development of Internet of Things (IoT) market and advanced technologies such as smart meters and smart thermostats allows for the design of novel strategies that address traditional challenges faced by electric grid operators. This dissertation elaborates on how smart buildings can leverage IoT-based solutions to participate in the electricity market during demand control periods. We also developed an expert opinion-based demand curtailment allocation scheme resulting in grid peak demand reduction. The numerical results obtained reinforce the effectiveness of the proposed solution across varied climatic conditions.

abstract: The building sector is responsible for consuming the largest proportional share of global material and energy resources. Some observers assert that buildings are the problem and the solution to climate change. It appears that in the United States a coherent national energy policy to encourage rapid building performance improvements is not imminent. In this environment, where many climate and ecological scientists believe we are running out of time to reverse the effects of anthropogenic climate change, a local grass-roots effort to create demonstration net zero-energy buildings (ZEB) appears necessary. This paper documents the process of designing a ZEB in a community with no existing documented ZEB precedent. The project will establish a framework for collecting design, performance, and financial data for use by architects, building scientists, and the community at large. This type of information may prove critical in order to foster a near-term local demand for net zero-energy buildings. / Dissertation/Thesis / Appendix M - Simulation and Weather Data / M.S. Built Environment 2014

The diploma thesis with research of efficiency of renewable and low-potential energy sources of buildings. It is available on numerical simulations for sharing office and heating and cooling system buildings in DesignBuilder. There are various energy sources and ways of controlling heating and cooling. The results are evaluated in terms of time, after the expected compromises in the building, in terms of energy consumption and its price.

This research work is focused on a conceptual combination of membrane-based energy recovery ventilator (ERV) and phase change material (PCM) to provide energy savings in building heating, ventilation & air-conditioning (HVAC) systems. An ERV can recover thermal energy and moisture between the outside fresh air (OFA) entering into the building and the exhaust air (EA) leaving from the building thus reducing the energy consumption of the HVAC system for cooling and heating the spaces inside the building. The membranes were stacked parallel to each other forming adjacent channels in a counter-flow arrangement for OFA and EA streams. Heat and moisture is diffused through the membrane core. Flat-plate encapsulated PCM is arranged in OFA duct upstream/downstream of the ERV thereby allowing for further reduction in temperature by virtue of free cooling. Paraffin-based PCMs with a melting point of 24°C and 31°C is used in two different configurations where the PCM is added either before or after the ERV. Computational fluid dynamics (CFD), and heat and mass transfer modeling is employed using COMSOL Multiphysics v5.3 to perform the heat and mass transfer analysis for the membrane-based ERV and flat-plate PCMs. An 8-story office building was considered to perform building energy simulation using eQUEST v3.65 from Department of Energy (DOE). Based on the heat and mass transfer analysis, it is found that the sensible effectiveness (heat recovery) stood in the range of 65%-97% while the latent effectiveness (moisture recovery) stood at 55%-80%. Also, the highest annual energy savings achieved were 72,700 kWh in electricity consumption and 358.45 MBtu in gas consumption.

Building energy usage can be derived and controlled by performing building energy modeling. BEM can be performed using numerous software tools such as DesignBuilder, OpenStudio, EnergyPlus etc. These modeling tools can be sorted into three different modeling categories: Black-box, Gray-box and White-box. It is important for a modeler to be able to quickly select the proper tool from the proper category to meet the need of the project. To validate the method of categorizing tools, the three models generated using tools from each category and the modeling outputs required were compared. Each model was designed to estimate the amount of heat transfer through building envelope elements. All the modeling tools were able to generate the required output, therefore, the method for selecting the most effective tool will be based on the output requirements and the time it takes to build the model, time it takes to generate the output and interpret the output.

Climate change is a global phenomenon that strongly affect cities and urban areas. Due to the intensive industrial activities and global population growth leading to more fossil energy demands for the last century, the global warming effect appeared to have been significantly exacerbated. To overcome the issues related to the increase of greenhouse emissions amplifying the global warming, multiple initiatives and engagements have appeared for the last 10 years in order to reduce our global energy demands and reduce the dependency to fossil energy and engage a transition to renewable energy. One way to achieve these objectives is to engage a technological and societal shift in the building industry by reducing energy demands and increasing local energy productions based on renewable energy or, at least, carbon neutral systems. In order to qualify these new types of construction, the concept of positive energy district (PED) has arisen through multiple initiative around the world. This thesis aims to assess the possibility to meet the PED requirements for the new Jakobsgardarna district extension project proposed by Sweco in Borlange, Sweden. This project is based on 144 buildings composed of schools, residentials, retails shop, and offices spread on an 80 ha of land. The Building Energy Modelling (BEM) has been performed on IDA ICE to assess the energy demands and energy production of the entire district following multiple scenarios. These simulations have been performed with either a district heating system or a heat pump as base system. Then, the models have been extended with photovoltaic (PV) panel in multiple configurations in order to find the bes tsolution to meet the PED requirements. First results of the baseline configuration (district heating) shows that the yearly energy demand was around 14,227 MWh which represent almost 69 kWh/m2, mainly dominated up to 75% by the heating demands including domestic hot water (DHW). Moreover, an uncomfortable situation has been met in almost all residential building during summer with temperature reaching up to 31°C. The second configuration considering a heat pump with bore holes in replacement of the district heating shows an overall yearly energy demands of 9,738 MWh representing 47.2kWh/m2 per heated area. This results in a 67% reduction of the energy demands in comparison with the base case. This is due to the high coefficient of performance (COP=4) of the heat pump compared to the district heating system’s (COP=1). In this configuration the heating demands still corresponds to 70% of the overall energy demands. The addition of PV panels compensated the entire electrical needs of the district when combined with district heating and even allowed to reach the positive energy requirements when combined with heat pumps with bore holes. The latter case generates up to 20% of electrical energy in excess of what it produced, even while considering solar panels at a15° of tilt angle in a region where the optimal inclination is defined at 45°. According to the preliminary results obtained in this study, positive energy requirements could be met by the combination of heat pump and PV panels according to our assumptions. This work could then be used to further refine the district design and propose suggestions to improve both the thermal modeling of the district and the design rules for architects and local stakeholders.

The diploma thesis is to bring knowledge from the field of energy and simulation evaluation of buildings. Further, there is an introduction to the issue of energy and environmental assessment, legislative documents. A brief procedure for creating an energy model in a simulation program, then setting the model. Evaluated results from DesignBuilder that are in the form of charts. And also the evaluation of the measured data in the form of graphs from Libuše object in Karlova Studánka.

The thesis deals with the environmental assessment of buildings, concrete objects Letní lázně at Karlova Studánka. The first part describes the issue and legislation. There is also described a method of experimental measurement and methods of moisture measurement. The second part deals with the analysis of the specified object, description of selected renewable sources and description of possible modifications of the object. The third part is devoted to modeling and simulation of the specified object in DesignBuilder. Using the model were created various simulations with various modifications in order to reduce energy intensity of the object. Results were then evaluated and compared.

The energy retrofit of existing buildings has always been a challenging task to accomplish. The example of the Swecohuset building, proves how an integrated approach design between architectural and energetic aspects as well as the use of well-known and efficient technologies are key aspects to achieve the energy-saving goal. This work, in the first part describes the Swecohuset retrofit process, along with the reasons behind the choices which have led to the current result of a reduction by 2/3 of the energy need for space conditioning purposes. Then, in the second part, after a brief focus on the passive aspects which characterize the current energy performance of the building, it is carried out a feasibility analysis of an EWIS (external wall insulation system) by studying its interaction with a complex system as an optimization problem, with the main purpose of understanding the basis of the BPO and explore further building potentialities. / SIRen