This study examines the use of building modeling and Energy simulations in the design process  of  a  building.  The  take-off  point  is  the  notion  of  energy  simulations  being needed early and throughout the building design process, and that the lack of Energy simulations may be explained by the fact that they are time consuming and therefore often too expensive. A greater interoperability between software tools used by relevant disciplines,  such  as  the  architect  and  the  energy  specialist,  would  create  smoother workflows, which would reduce this cost and open up for more frequent and iterative energy  simulation  processes.  The  study  is  an  assessment  of  the  modeling  tool  Revit and  the  simulation  tool  Virtual  Environment  and  whether  they  can  create  smoother workflows, and make leeway for a more frequent use of Energy simulations throughout the  design  process.  It  also  investigates  the  limitations  of  what  can  be  examined  by simulations in Virtual Environment. This will hopefully help clarify the future role of energy  simulations  in  design  processes.  The  method  is  a  trial  by  error  approach  of testing the two software tools by building and simulating a model. The results of these tests  show  that  the  workflow  is  not  optimal  (and  therefore  time  consuming)  for frequent  and  iterative simulations  throughout the  design  process,  but  it  also  reveals some  great  possibilities  of  what  can  be  performed  with  these  two  powerful  tools  at hand.  Further  development  with  regards  on  platform  independency  of  the  building information  model,  including  seamless  exporting  and  importing,  seems  necessary  to strengthen the future role of Energy simulations..

Since Energy simulations are used to verify that projected residential buildings will reach the current energy requirements it is important that the results are reliable.This report investigates the extent of uncertainty in Energy simulations, estimates the causes of the uncertainty and its economic and environmental consequences.The method used in this report is based on three validation methods; empirical validation, analytical validation and comparative validation. The analysis was carried out for five multi-family dwellings in Uppsala with installed meters for energy measurements. One of these objects, Klockarlunden, was studied in more detail than the others.The results show that the deviations are between 10 and 29% for the studied objects, which means that the uncertainty is estimated to be at least 29%. All simulations underestimate the buildings need of energy. The simulation for Klockarlunden can predict the energy consumption to be within the range of 46-98 kWh/m2year with 90% confidence level based on the current uncertainty.

This report is the result of a degree project in building engineering, at an advanced level. The project evaluated a building from a technical and historical point of view, and focused on its energy consumption, particularly the energy used for heating. The building in question was a small apartment building in Strömsholm, Sweden. It was made in 1902, from vertical logs, a not so common form of the traditional log house. The goal of the project was to evaluate if the energy consumption could be reduced in accordance with building preservation regulations, that is without damaging any of the building?s cultural or historical values.The building was surveyed with the help of archive and literature studies, interviews and inspections.

In the spring of 2014 Sweco Systems AB were commissioned to design a ventilation system for a newly built preschool in Linköping. Terms from the client was that it cost efficiency would cope with the energy demands that are placed on the building. The unit chosen was a cross-flow heat exchanger, and this work is to compare it with two other heat exchangers to see if a more energy and cost efficient could have been chosen. The heat exchangers that was chosen for the comparison was a rotating- and a counterflow heat exchanger. Simulations have been made to the different heat exchangers by the manufacturers.

In this thesis, the Train Power System Simulator (TPSS) has been compared and verified with the commercial simulator TracFeed® Simulation (TracFeed). The basis for the comparison was a given part of the Swedish railway system, with steel transportation trains. Primarily, emphasis was placed on running time and energy consumption in simulation results. Two transformer systems were analyzed, booster and auto transformers. The high voltage transmission line, parallel to the railroad track, was disconnected in some simulations.

In the spring of 2014 Sweco Systems AB were commissioned to design a ventilation system for a newly built preschool in Linköping. Terms from the client was that it cost efficiency would cope with the energy demands that are placed on the building. The unit chosen was a cross-flow heat exchanger, and this work is to compare it with two other heat exchangers to see if a more energy and cost efficient could have been chosen. The heat exchangers that was chosen for the comparison was a rotating- and a counterflow heat exchanger. Simulations have been made to the different heat exchangers by the manufacturers.

The question of excessive global energy use needs to be solved. All energy production and usage have negative environmental impacts, which are best solved by reducing energy consumption and by using energy more efficiently. A large part of the Swedish energy use is concentrated to the building sector and to reduce the total energy consumption real efforts need to be made to make buildings more energy efficient.The aim of this study was to investigate how energy is used in one of Göteborg University?s buildings and to find measures that can be taken to improve its energy efficiency. The chosen building Zoologen, is used for research and education.The main method of the study is computer simulations of the present building and of possible energy reducing measures to be made in the future.

An energy study has been performed on two blocks in an area called Gävle Strand. The buildings are owned by a tenant-owner?s association called brf Carolina and were built by the company Skanska 2008. The builder as well as brf Carolina are pussled by the fact that electricity use is higher than expected while heating is less. Skanska is also very interested in finding out how much heat recovery from stale exhaust air through a geo-thermal heat pump is contributing to the general heating requirement and energy balance in four out of the ten buildings located on the properties.To find possible answers to the higher electricity use a literature survey on user behaviour was conducted.

An energy study has been performed on two blocks in an area called Gävle Strand. The buildings are owned by a tenant-owner?s association called brf Carolina and were built by the company Skanska 2008. The builder as well as brf Carolina are pussled by the fact that electricity use is higher than expected while heating is less. Skanska is also very interested in finding out how much heat recovery from stale exhaust air through a geo-thermal heat pump is contributing to the general heating requirement and energy balance in four out of the ten buildings located on the properties.To find possible answers to the higher electricity use a literature survey on user behaviour was conducted.

Tången 2 is a building situated in Stockholm, Sweden. It´s built in the 1930s and contains both residences and businesses. The property owner, Diligentia AB, wants to lower the energy use in Tången 2. This report consists of an energy audit which clarifies the specific circumstances linked to Tången 2. Collected knowledge is then used, together with the results from the literature study, to decide energy measures to proceed with.

In Uppsala, Sweden, Vattenfall has a combined heat and power plant. On the premises there is an engineering workshop with old fluorescent and mercury lamps that need to be replaced. This provides a great opportunity to save energy and money by installing more efficient lighting. The main purpose of this study was to present two functional and energy efficient lighting systems including control system. The lighting systems were designed by investigating the working environment, measuring illuminance and by simulations in the software DIALux.

WSP building physics in Stockholm has certified the preschool Temmelburken in Bromma with the system of certification Miljöbyggnad. The rating of the building became BRONZE. In this thesis the preschool has been investigated with respect to the three areas: thermal climate, use of energy and improving of the level of certification. The thermal climate at the preschool has been investigated by a questionnaire survey and by measurements in order to do comparisons between the results from the two investigations as well as with the results of the simulations that WSP has done at the certification of the preschool. The differences between the results from the simulations and the questionnaire survey for winter as well as from the measurement performed with a comfort meter the 19th of March are concidered to be reasonably small since they give rise to the same rating according to Miljöbyggnad.   Operational data for the use of energy for the preschool have been obtained in order to do comparisons with simulations performed by WSP and Svenska Besiktningar AB. The comparison shows that the simulated values for the specific use of energy are lower than what the real specific use of energy would be for the preschool, since just the operational data for the heat energy is higher than the simulated values. At the investigation of the possibility of improving the level of certification it was found that the rating of the preschool can be raised from BRONZE to SILVER by improving the ratings of the ?thermal climate summer? and the ?daylight?.

The regulations for energy consumption are consistently getting more and morestrict. This leads to a higher customer demand for energy analysis early in the buildingdesign process. Many building planners and architects use powerful modeling softwareto visualize their projects. These digital models contain sufficient information aboutthe building?s physical characteristics for reliable energy analysis.

The energy consumption in the sectors of residential and public buildings is 40 % of the total energy consumption in Sweden. The main part, 85 %, of the energy use in these sectors is for operation of the buildings. The rest is used in the building process. When energy-efficiency measures are taken the energy use during the operation time decreases and the fraction of energy consumption during the building time increases. This project is carried out in cooperation with JM AB and concerns the energy use during the building time of production of blocks of flats at the building site.The main part of the electricity that is used during the production of apartment buildings goes into the heating of portacabins and illumination of the building during the construction phase.

Climate and environmental issues is now high on the agenda. We live in a generation that must try to solve some major environmental problems. Buildings and habitations account for approximately 40 % of Sweden's total energy today. To reduce this figure, as needed, more research in the field of energy efficiency is required.This thesis concerns the heating of buildings. The load on district heating is heavy during certain times of the day.