<p>This project discusses the effect of reducing the amount of fresh air supplied mechanically to a typical Swedish house, remaining constant the amount of air removed from the building. The new ventilation technique studied through this project is used by the so-called FtX ventilation systems, whose main difference comparing to FTX ones is that the supply airflow rate is reduced.</p><p>This reduction of the supply airflow rate is simulated by means of commercial software called IDA Indoor Climate and Energy, which provides the energy consumption in the dwelling so as the temperature in the building and the different airflows. Firstly, the model of the house is built in IDA taking into account the regulations established by the Swedish Building Code and the materials and size of a typical construction in Scandinavian region. The building is located in Bromma, near Stockholm. The reason to situate the building in this place is that IDA ́s database contains the meteorological data registered in this location during a whole year, so yearly simulations can be carried out using real meteorological data.</p><p>After simulating every model, results are gathered and compared. On the one hand, an energy study is carried out for a whole year in order to determine the optimal quotient between the supply airflow rate and the exhaust airflow rate which minimizes the energy consumption. This study indicates that when the supply airflow rate is 0.95 times the exhaust airflow rate, the energy consumed by the building is minimal. On the other hand, an economical study is done. To calculate the economical cost of the energy purchased by the building, the tariffs of a company which sells district heating and electricity in Stockholm are used. Considering these data and the energy consumption for the whole year, it is calculated the economical cost in each case. The optimal ventilation rate, in monetary terms, is (Qs/Qe) ≅0.9. In this case, the energy cost amounts to 13,880 SEK.</p>

This project discusses the effect of reducing the amount of fresh air supplied mechanically to a typical Swedish house, remaining constant the amount of air removed from the building. The new ventilation technique studied through this project is used by the so-called FtX ventilation systems, whose main difference comparing to FTX ones is that the supply airflow rate is reduced. This reduction of the supply airflow rate is simulated by means of commercial software called IDA Indoor Climate and Energy, which provides the energy consumption in the dwelling so as the temperature in the building and the different airflows. Firstly, the model of the house is built in IDA taking into account the regulations established by the Swedish Building Code and the materials and size of a typical construction in Scandinavian region. The building is located in Bromma, near Stockholm. The reason to situate the building in this place is that IDA ́s database contains the meteorological data registered in this location during a whole year, so yearly simulations can be carried out using real meteorological data. After simulating every model, results are gathered and compared. On the one hand, an energy study is carried out for a whole year in order to determine the optimal quotient between the supply airflow rate and the exhaust airflow rate which minimizes the energy consumption. This study indicates that when the supply airflow rate is 0.95 times the exhaust airflow rate, the energy consumed by the building is minimal. On the other hand, an economical study is done. To calculate the economical cost of the energy purchased by the building, the tariffs of a company which sells district heating and electricity in Stockholm are used. Considering these data and the energy consumption for the whole year, it is calculated the economical cost in each case. The optimal ventilation rate, in monetary terms, is (Qs/Qe) ≅0.9. In this case, the energy cost amounts to 13,880 SEK.

Projektet omfattade undersökning och framtagande av ett solcellssystem med förmåga att försörja ett FTX-system i ett flerbostadshus från miljonprogrammet med el. För att kunna bedöma storlek och utformning av komponenter har information tagits genom: Informationssökning via databaser, kurslitteratur och intervjuer Simuleringar av solceller i datorprogrammet PVSYST Modulering av ventilationskanaler i datorprogrammet MagiCAD Syftet var främst att undersöka om det gick att få fram ett teoretiskt fungerande system med avseende på både solceller och ventilation. Beroende på vad resultatet blev skulle även ekonomin i projektet undersökas. Undersökningen visade att det teoretiskt ska gå att installera solceller för elframställning som klarar av att täcka FTX-systemets elbehov på årsbasis. Solcellerna bedöms även producera tillräckligt med el för viss övrig elkrävande utrustning under stora delar av året. Det visade sig även att det skulle gå att få solcellerna ekonomiskt lönsamma om en kalkyltid på 14 år används. Metoden som använts för dessa resultat är noga beskriven och är med små förändringar tillämpbar för ett stort antal byggnader i det svenska byggnadsbeståndet. En viktig slutsats är att om fastighetsägarna kan se 15 år fram i tiden för en investering i solenergi, skulle det innebära inte bara miljömässiga utan även ekonomiska vinster. Det finns redan idag kunnande, teknik och produkter för att utvinna en stor del av fastigheternas elbehov genom solens energi. / The project is a feasibility study of including the installation of solar cells and an FTX ventilation system in the renovation of a Swedish million program multi-family ouse. The question concerns whether the energy production of the PV system can match with the energy consumption of the FTX-system. Input data was obtained from: Databases, literature and interviews. Simulations of photovoltaics modules in the computer program PVSYST Modulation of the vents in the computer program MagiCAD The aim was primarily to investigate whether it was possible to get a theoretical working system. The economy of the project should also be investigated depending on the results. The study showed that it should be theoretically possible to install photovoltaics for electricity generation that is able to cover the FTX system's electricity needs on a yearly basis. The photovoltaics are also expected to produce enough electricity for some other equipment that requires electricity for much of the year. It was also found that it should be possible to get the photovoltaics modules economically viable if a pay-back time of 14 years was used. The method used for these results is thoroughly described and with small changes applicable to a large number of buildings in the Swedish building stock. An important conclusion from the project is that if property owner can see 14 years into the future with an investment in solar energy, there is much to be gained. There are already skills, available technologies and products available in order to recover a large portion of the properties' electricity needs through solar energy.

L’inactivation du chromosome X (XCI) est un mécanisme qui permet l’extinction transcriptionelle d’un des deux chromosomes X chez la femelle. XCI est régulé par une région spécifique nommée centre de l’inactivation du chromosome (Xic), contenant plusieurs gènes produisant de longs ARNs non codants (lncRNAs). Parmi ces lncRNAs, le transcrit Xist est l’effecteur principal pour l’XCI. Xist peut s’accumuler en cis sur le chromosome et recruter la machinerie qui permettra l’initiation et la propagation de l’extinction transcriptionnelle à l’échelle du chromosome.Le laboratoire d’accueil a identifié un nouveau gène du Xic qui produit le lncRNA Ftx. Dans cette étude, on a pu montrer que l’inactivation du chromosome X est fortement perturbée dans les cellules Ftx-/- et s’accompagne par une forte baisse du niveau d’expression et d’accumulation de Xist. Dans ce contexte, certaines cellules parviennent à maintenir l’expression de Xist mais le profil de couverture du chromosome X par Xist est anormal, présentant un profil diffus ; ceci est associé à une extinction transcriptionnelle déficiente des gènes liés à l’X. Dans les lignées hétérozygotes Ftx+/-, l’expression et l’accumulation de Xist est aussi affectée mais dans une moindre mesure, si bien qu’il apparaît que le nombre de copies de Ftx soit important pour sa fonction. Par ailleurs, l’inactivation du chromosome X dans les cellules Ftx+/- est biaisée de telle sorte que le chromosome X portant une copie fonctionnelle de Ftx est préférentiellement inactivé, suggérant un rôle en cis de Ftx. Ces résultats montrent que Ftx est un activateur de Xist et qu’il est essentiel pour la mise en place de l’inactivation / X-chromosome inactivation (XCI) is a female-specific, chromosome-wide regulatory process that, in eutherians, ensures dosage compensation for X-linked genes between sexes. XCI is controlled by a cis-acting locus on the X-chromosome, the X-inactivation center (Xic), enriched in genes producing long non-coding RNAs (lncRNAs). The Xic-linked gene Xist is the master player of XCI, and produces a lncRNA that accumulates in cis on the X-chromosome and recruits the machinery responsible for initiation and propagation of silencing.The laboratory has identified an additional Xic-linked non-coding gene, Ftx. In this study, we could find that, in female Ftx-/- lines, XCI is strongly impaired, with a significant decrease in the levels of Xist expression and in the percentage of cells showing normal Xist accumulation patterns. Importantly, a high proportion of the cells that still retain Xist expression show abnormal X-chromosome coating and a decreased ability to silence X-linked genes. These data reveal that Ftx is a positive Xist regulator and it is required for proper XCI establishment. In female Ftx+/- lines, the levels of Xist expression and the percentage of cells showing normal Xist accumulation patterns are also decreased, albeit to a lower extent compared to Ftx-/- lines, suggesting that Ftx works in a copy-dependent manner. In addition, a high proportion of Ftx+/- cells display skewed X-inactivation, with preferential inactivation of the wild-type X chromosome. This suggests that Ftx role on Xist accumulation is mostly restricted in cis. Taken together, these results demonstrate that Ftx is required for XCI establishment, where it functions as a strong Xist activator

The purpose of this report is to survey the multi-family residential buildings that were built in the Swedish city of Uppsala during the state-funded Million Homes Program and to assess the technical potential of different energy efficiency measures that may be applied in order to improve the efficiency of the heating of these buildings. An additional purpose of this report is to discern how the entire district heating system would be affected if the proposed energy efficiency measures were implemented.   The energy efficiency measures that were examined were: improved thermal envelopes (additional insulation and energy efficient windows and doors) and installation of air-to-air heat exchangers or exhaust air heat pumps in the ventilation systems. The buildings were categorized into four different types of buildings with different properties and a model was constructed for each category.   All energy efficiency measures showed significant reductions in the amount of heating required. The measure with the best performance was improvement of thermal envelopes in combination with exhaust air heat pumps, which reduced the buildings' energy demand by about 80%. Regarding the heat demand in the entire district heating system, the reductions due to energy efficiency measures in the million homes program buildings were small. The exhaust air heat pumps showed the largest reductions in the capacity factor. Only the heat exchangers resulted in a higher capacity factor and the improvement was too small to be of interest. However, the results clearly show that saving energy in space heating is technically easily achievable.

This report is the result of a thesis conducted at the consulting firm Bjerking AB andis the final part of the Bachelor Programme in Construction Engineering at Universityof Uppsala. The work aims to investigate the costs and how the choice of ventilationsystem affects building projects during a long-term period. This report covers costssuch as investment, maintenance and energy but also how they affect residents andbuilders. Building regulations for energy consumption are expected to be tougher;therefore a comparison of two different heat recovery ventilation systems(HRV-system) was made. One system is based on a centrally placed unit that coversthe whole buildings ventilation through vertical shafts. The second system is based onapartment placed unit that only covers the individual apartment’s ventilation. The unitmakes it possible for the individual user to control the ventilation flow.The method used for comparison of the costs was Life Cycle Cost (LCC). It results inthe total cost during a selected calculation period of 20 years, where yearly basedcosts as energy and maintenance is included. Two housing projects in central Uppsalawere chosen as a reference. They were similar in design but with the two differentsystems of ventilation. A questionnaire was handed out to provide experience fromresidents with apartment units. The results were used in the analysis of the systemsand to determine its pros and cons.Information of costs was collected from different companies and resulted intocustomized spreadsheets to determine the cost per apartment. The result shows thatthe difference in investment is not significant between the systems but is big inmaintenance and energy. The biggest difference is maintenance where the apartmentsystems many service points is increasing the cost. Energy consumption for theapartment system leads to higher energy costs than with a central system, even if thecontrol function is used. The explanation is that a central systems fans have lowerpower usage and the heat recovery is more efficient then an apartment system.The conclusion is that a central system has a lower total cost compared to anapartment system during the calculation period. A reason for choosing the apartmentsystem would be if a need to maximize living space is a priority, and the developingphase of the project is well thought thru.Keywords: LCC-analysis, HRV-systems, Central unit, Apartment unit.

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Utifrån ett effektiviseringsperspektiv beror en byggnads inomhusklimat på flera enskilda system som tillsammans tillför och balanserar erforderligt energibehov till byggnaden, och samtidigt har de växelverkan med varandra. Systemen är uppvärmningssystem, kylsystem, ventilationssystem, samt styr-och reglersystem som spelar roll av hjärna för de andra. I detta examensarbete är ventilationssystemet i fokus. Numera finns i Sverige olika typer av ventilationssystem. Ett av de vanligaste ventilationssystemen är till-och frånluftsventilation med värmeåtervinning, typ FTX som har två fläktar. Fläkten är en huvudkomponent i ett mekaniskt ventilationssystem och dess skovlar är avgörande för skapande tryck och kan utformas på olika sätt. I Brf. Mörbylund 11–15 i Danderyd kommun tänker föreningen vidta några effektiviseringsåtgärder som ska sänka elkostnaden för 3 stycken luftbehandlingsaggregat. I de allra flesta fall beror hög elförbrukning på gamla fläktar i FTX-system som har höga specifik fläkteleffekt, eller SFP-tal. För att sänka elenergin på aggregaten krävs det att undersöka olika parametrar som gäller aggregaten. Därför behövs mätvärden av parametrar såsom lufttryck, flöde, fläktsverkningsgrad, elförbrukning till fläktar och shuntgrupper som kopplas till luftvärme i aggregaten. Därefter jämförs mätningar över befintliga samt nyinstallerade fläktar, och shuntgrupper. Vid undersökning av de uppmätta parametrarna över befintliga respektive nya komponenter leder det till ett ekonomiskt resultat som speglar konsekvensen av de vidtagna åtgärderna i luftbehandlingsaggregaten. Teorin i denna rapport beskriver de viktiga komponenterna och delarna i ett ventilationssystem, och baseras bland annat på “Projektering av VVS-installationer” av C. Warfvinge &amp; M. Dahlblom. I teoridelen visas flera statistiska fakta kring användning av olika ventilationssystem i Sverige, samt mest ligger fokus på den typen av ventilationssystem som finns i Brf. Mörbylund 11–15, FTXsystem. Under titeln, “Mätmetoder” kommer en del förklaringar av tryckfallberäkning, flöde och fläktdiagram. I teoridelen diskuteras också regler och förutsättningar som presenteras av BBR i detta område som kan hittas i avsnittet, “Myndighetskrav”. Vidare beskrivs det studerade objektet och dess komponenter. I den ekonomiska delen visas två olika kalkylmetoder. Den ena som används av HSB-företag och den andra som väljs av författaren till rapporten för att beräkna möjlig vinst. De är pay-back, och annuitetsmetod. Pay-back-metoden har till nackdel att inte ta hänsyn till låneränta och ekonomisk livslängd vilket däremot är avgörande för annuitetsmetod. Resultatet av annuitetsmetoden visar en negativ summa för kalkylering fastän själva åtgärden är energieffektiv. Det negativa resultatet kan tolkas på olika sätt. Exempelvis kan det bero på olika arbete mellanhänder (mäklaren) som finns mellan föreningen och den första aktören som tillverkar och säljer de önskande komponenterna. I rapporten presenteras och undersökas olika möjliga förklarningar.

Detta examensarbete beskriver miljöpåverkan från ett ventilationssystem, utifrån ett småhus i ett nordiskt klimat, ur ett livscykelperspektiv. Ett balanserat ventilationssystem med värmeåtervinning orsakar en stor andel av en fastighets totala miljöpåverkan och är därför viktigt som fokusområde för reducering av byggsektorns miljöpåverkan. Livscykelanalys är en vedertagen metod för att beskriva och jämföra en produkts miljöbelastning under alla dess faser. Miljöpåverkan har modellerats med hjälp av mjukvaran SimaPro 8.0.2, utifrån data framtagen från byggvarudeklarationer samt momentant uppmätta värden av fläkteffekter och luftflöden. Äldre livscykelanalyser har påvisat en mångfaldigt högre miljöpåverkan från användningsfasen jämfört med tillverkningsfasen. Senare studier visar dock en viss utjämnad fördelning mellan faserna där tillverkningsfasens relativa betydelse ökat, vilket även bekräftas i detta examensarbete där tillverkningsfasen står för ungefär 36 % av den totala miljöpåverkan (inklusive utbyte av komponenter). Enligt miljöpåverkansmetoden ReCiPe 2008 medför det studerade systemet betydande miljöpåverkan genom användandet av fossila bränslen, både vid användning och tillverkning, vilket föranleder klimatförändringar genom utsläpp av växthusgaser. Det sker även omfattande utsläpp av partiklar till luft från båda faserna och användningsfasen medför stor påverkan genom upptagande av jordbruksbar mark. De enhetsprocesser i produktsystemet som främst orsakar miljöpåverkan är elanvändning för drift av fläktar och eftervärmning av tilluften, samt tillverkning av olika stålkomponenter. Studien åskådliggör dessutom hur en förhållandevis enkel åtgärd för effektivisering av användningsfasen signifikant reducerar miljöpåverkan i användningsfasen, utan att påverka inomhusklimatets kvalitet. / This thesis describes the environmental impact from a balanced ventilation system with heat recovery from the perspective of a single-family home, in a Nordic climate. A balanced ventilation system with heat recovery contributes with a major part of a buildings total energy usage. Thus, it´s an important focus area towards minimizing the environmental impact from the building sector. Life cycle assessment is an established method to illustrate a products environmental impact during all its phases. The environmental impact has been simulated with the LCA-software, SimaPro 8.0.2. The life cycle inventory is based on various data from building product declarations as well as measured instantaneous values of air flow and the power of the fan motors. Older LCA-studies have shown a much greater environmental impact from the operational phase compared to the embodied impact from the construction phase. However later studies demonstrate a more equalized allocation between these two major phases, which is confirmed in this thesis where 36 % of the environmental impact could be derived to the construction phase. According to the environmental impact method, ReCiPe 2008, considerable impact is created from the usage of fossil fuels, which contributes to climate change as a result of greenhouse gas emissions. Significant impact is also generated by the formation of particulate matter and agricultural land occupation. The unit processes which generated the greatest environmental impact is electricity usage for operating the fans and heating of the supply air, together with manufacturing of steel components. The thesis is also examining how a relatively simple measure, that makes the usage phase more energy efficient, significantly reduces the environmental impact without affecting the indoor climate.

The choice of heating system and to add heat recovery is becoming increasinglyimportant in order to meet the climate goals. The need for renovation of homesbuilt in the so-called million program is extensive. The purpose of the work is toevaluate two different ventilation systems and its profitability in connection withthe renovation of a property in Ljungby. The systems to be compared are asystem with presence-controlled FTX-apartment units and a system with exhaustair heat pumps. The goal is to present a result about which ventilation systemleads to the largest energy and cost savings compared to the existing ventilationsystem in the property.The results show that the ventilation system with presence-controlled FTXapartment units in each apartment should generate the lowest primary energy.The life cycle cost analysis showed that the most economically profitableventilation system is with FTX apartment units. The results also showed thatprojected and calculated average heat transfer coefficient can vary markedly. Insummary, the best choice is FTX apartment units with presence control. Thesystem consumes less energy than the FVP system, while avoiding dependenceon electrical energy.