Syftet med detta arbete var att dimensionera lämplig kylmaskin för en tillbyggnad av en ytterligare ishall bredvid befintlig ishall. Ishallarna som studerades var på LF-Arena i Piteå Kommun. Utöver dimensioneringen utvärderades möjligheter för värmeåtervinning från kylmaskinen. Kylmaskinens livscykelkostnad (LCC), återbetalningstid och miljöbesparing utvärderades också. Arbetet undersökte två olika alternativ av kylmaskiner, det första alternativet var en ammoniak- (NH3) kylmaskin och det andra alternativet var en koldioxid- (CO2) kylmaskin.   Dimensioneringen av den nya kylmaskinen gjordes med information om den befintliga kylmaskinen och antaganden för den nya ispisten. Information om den nya kylmaskinen uppmättes med hjälp av mätutrustning anpassade för kylsystem. Värmebehoven för anläggningen var: Lokalvärme, tappvarmvatten, tining av is i smältgrop, fyllning av ismaskin, köldskydd, avfuktning och markvärme till fotbollsplanen. De olika värmebehoven utvärderades och beaktades i utformningen av det nya kylsystemet.   Resultatet visade att kyleffektbehovet för de båda ispisterna blev sammanlagt 700 kW. Det visade sig att CO2-aggregatet var det bästa alternativet för att spara maximalt med energi. I detta fall kunde värmeåtervinning från CO2-kylmaskinen tillgodose hela ishallens hög- samt lågvärdiga värmebehov. För att nyttja värmeåtervinning till markvärme för fotbollsplanen var NH3-kylmaskinen ett bättre alternativ, den kunde tillgodose 93% av värmen i detta fall. CO2-aggregatet kunde tillgodose 78% av värmebehovet till markvärmen. Ur både ett ekonomiskt- och miljömässigt perspektiv var CO2-aggregatet ett bättre alternativ med en LCC och återbetalningstid på 15,5 Mkr och 4,4 år. Beroende på hur stor del av elanvändningen som är lokalproducerad så kunde miljöutsläppen minskas med 3 – 14,7 ton CO2e per år i detta fall jämfört med NH3-aggregatet som kunde minska miljöutsläppen upp till 13,8 ton CO2e. / The purpose of this work was to dimension an appropriate refrigeration system for an extension of an additional ice rink next to the existing one. The ice rinks studied were located at LF-Arena in Piteå Municipality. In addition to dimensioning, opportunities for heat recovery from the refrigeration system were evaluated. The life cycle cost (LCC), payback period, and environmental savings of the refrigeration system were also assessed. The work examined two different options of refrigeration systems, the first option being an ammonia (NH3) refrigeration system and the second option being a carbon dioxide (CO2) refrigeration system.   The dimensioning of the new refrigeration system was done with information about the existing system and assumptions for the new ice surface. Information about the new refrigeration unit was measured using equipment adapted for refrigeration systems. The heat requirements for the facility included: space heating, domestic hot water, ice melting in the pit, filling of the ice machine, frost protection, dehumidification, and ground heating for the football field. The different heat requirements were evaluated and considered in the design of the new refrigeration system.   The results showed that a cooling capacity of 700 kW for both ice rinks combined was needed. It was found that the CO2-system was the best option for maximizing energy savings. In this case, heat recovery from the CO2 refrigeration system could meet the entire high- and low-grade heat demand of the ice rink. To utilize heat recovery for ground heating for the football field, the NH3 refrigeration system was a better option, as it could meet 93% of the heat demand in this case. The CO2-system could meet 78% of the heat demand for ground heating. From both an economic and environmental perspective, the CO2-system was a better option with an LCC and payback period of 15.5 million SEK and 4.4 years, respectively. Depending on the proportion of locally produced electricity consumption, emissions could be reduced by 3 to 14.7 tons of CO2e per year in this case compared to the NH3 unit, which could reduce emissions by up to 13.8 tons of CO2e.

I detta examensarbete undersöktes möjligheten att installera värmeåtervinningssystem för ett flerfamiljehus i Hovgården som ligger en bit utanför Borlänge. I rapporten redovisas två olika sätt för energibesparingar som är aktuella för att ersätta borttagning av oljepannan som används i huset i dag. En rad svårigheter dök upp under undersökningen för installation av nytt värmesystem. Lämpliga lösningar kunde hittas efter mycket analys. Syftet med rapporten var att undersöka möjligheten och lönsamheten för installation av något av följande system; FVP eller VBX-modul som kan återvinna värme ur frånluften. Undersökningen visade att varken VBX eller FVP kan ersätta oljepannans värmeavgivning på ett tillfredsställande sätt. Med VBX ökas COP från 2,8 till 3,11 vilket leder till 17 MWh/år elbesparing. Däremot FVP kan försörja huset med 59 MWh/år men kan inte täcka effektbehovet för gården under kallaste dagarna. Resultatet blev att de båda undersökta systemen inte har möjlighet att ersätta oljeeldning. / In this thesis, we have studied a building located in Hovgården in Borlänge. The report investigates two energy saving installations that can help to reduce the amount of oil used today in the house. The purpose of the report was to examine the possibilities and viability of exhaust heat pump (FVP) and VBX module that can recover heat from the exhaust air. The investigation showed that neither VBX nor FVP can replace the oil-fired boiler in an acceptable way. With VBX the COP of the existing heat pump is increased from 2.8 to 3.11 leading to 17 MWh/year electricity saving. However FVP can recycle 59 MWh/year from the exhaust air but still cannot cover the power demand of the building during the coldest days. The result was that the two investigated systems are not able to replace oil heating.

Drain water heat recovery is an uncommon measure in multi-unit residential buildings. There is technology available for the purpose but the knowing and experience of the heat recovery systems is little. The purpose of this thesis is to evaluate the future potential of drain water heat recovery in multi-unit residential buildings. A major part of the multi-unit residential buildings in Sweden were built during modernismen and rekordåren (1940 – 1975). Many of the buildings have worn out drain and water supply systems and many are in need of a general refurbishment. If drain water heat recovery is considered for a building it is suitable to install the recovery system at the same time as the refurbishment to minimize the installation cost. Existing heat recovery systems consist of heat exchangers, heat pumps or a combination of both. There are passive heat exchangers that are placed close to the shower, on the vertical drain pipe and on the horizontal drain pipe. Recovery systems comprising heat pumps are more complicated and space demanding. They are rarely suited for multi-unit residential buildings but have the potential of recovering more heat from the drain water. In some buildings, where heat recovery systems have been installed, the performance of the systems has been measured. The measurements show that passive heat exchangers can recover about 10 – 15 % of the hot water energy consumption, not including standstill losses and hot water circulation. Calculations indicate that the energy savings for passive heat exchangers could be 20-25 %. If several kinds of heat exchangers are combined the energy savings could be almost 40 %. Recovery systems with heat pumps could generate even larger energy savings, between 50 – 70 %. However, with heat pumps the electricity consumption increases and that has to be considered in profitability calculations. When developing new heat recovery systems the emphasis should be on energy storage and reactivity since most taps are short and unpredictable. In a technology procurement there should be demands on energy effectiveness. Based on experience from installed heat recovery systems and calculations the following is suggested:  The buildings heating and hot water energy consumption must decrease with at least 15 % of the current hot water energy consumption.  The buildings heating and hot water energy consumption should decrease with at least 20 % of the current hot water energy consumption. Furthermore there should be demands on profitability. The present value of future energy savings ought to exceed the investment cost and the present value of future costs of the system within a period of time. The following is suggested:  The condition must be fulfilled within 20 years  The condition should be fulfilled within 15 years iii

Energy efficiency and reduced energy consumption are two highly discussed topics in the global environmental debate where Sweden as a country is at the forefront. High demands on streamlining energy usage exists where a goal is to by 2030 have a 50% more efficient energy use than in 2005. This study examined how waste heat could be recovered from an industrial process to reintroduce it into the building and thus reduce energy consumption. The process included a test room for large motors at ABB Machines in Västerås, where a fire pond near the building was used as cooling water for the motors' cooling systems during testing. The fire pond was located underground and only the outdoor climate controlled the temperature of the water in the pond. This meant that for large parts of the year the water was too hot to be used as cooling water and thus there was a need to reduce the temperature of the pond and at the same time utilize the heat that was in it. Mass balances were performed on the fire pond using test protocols. In this way, the group was able to calculate how much energy was available to be utilized and what system temperatures were possible. After analysis of previous studies, a system solution was developed where the incoming cold water that would become domestic hot water was used to cool the fire pond and at the same time preheat the cold water. Calculations were made to prove the economic and environmental benefits of the solution. The result showed a saving of 121.89 MWh/y in district heating consumption, which corresponded to a decrease of 3.1% of the total district heating consumption. In figures, this corresponded to a gross saving of 66,730 SEK/year. In addition, the solution reduced cold water consumption by 3200 . The study showed that economic and environmental savings could be made but that the system solution was difficult to generalize as the current problem was unique. The group discussed other solutions that would have been possible if other conditions had existed for the fire pond. Among these was, for example, a proposal to upgrade the heat in the fire pond with the help of heat pumps and use this for the building's radiator circuit or for the primary district heating line. Objections to these proposals were that energy needed to be added to power the heat pumps.

The construction sector today accounts for 20 precent of Sweden's climate impact and 40 percent of energy use. This purpose of this study is to identify the most effective measures to reduce the grocery store's energy needs. The building is tempered primarily with district heating respectively district cooling that operates the air units' cooling and heating batteries. There are many efficiency measures that are feasible for grocery store's energy usage. This study calculates a under construction grocery store's energy needs and analyses which measures can reduce the total need for purchased energy. This study calculates both property energy and industry energy and then compare the economy and environmental impact of the various measures. This store has also been environmentally certified according to the Sweden Green Building Council system. The simulation program IDA ICE is an effective tool that allows information in the form of energy analysis to be evaluated. This study compares the retail chain's own energy solutions with new innovative solutions that can save energy and money. This study's focus is on energy saving measures from ventilation systems, cooling systems and heating systems. Measures examined in this study are: •         Solar cells on the property's roof •         Additional insulation of ceilings and floors •         Heat recovery of the grocery refrigeration system •         Heat recovery of the industry ovens The total property energy was 2,000 MWh or 150 kWh/m2. Heat recovery of the cooling system saves 500 MWh annually, which corresponds to 37 kWh/m2. Installation of 4,000 m2 of solar cells saves 480 MWh, which corresponds to 35 kWh/m2. The measure that is most optimal from an energy point of view is heat recovery from the refrigeration system. The measure that is most economically profitable is the installation of solar cells. The measure that saves the most carbon dioxide is heat recovery from the refrigeration system. The comparison showed that heat recovery is the most profitable measure. After the implementation of all measures, the store reaches Swedish environmental class "environmental building gold".

In this master’s degree thesis potential utilization of excess heat on Gotland is investigated. The report first identifies potential sources and users of excess heat and creates seasonal heat profiles for a few of them. The heat profiles are then matched and studied from technical, economic, and environmental perspectives to provide a comprehensive understanding of the investigated cases. The study reveals that large scale refrigeration systems and greenhouses, data centers and greenhouses, and electrolysers and ultra-pure water purification processes could potentially benefit from synergies created by excess heat utilization. However, challenges such as mismatched heat profiles and the risk of investments in excess heat capture technology may hinder such collaborations.

Idag ställs stora krav på företag att vara miljömedvetna och resurseffektiva i sin verksamhet. Vid mjukpapperstillverkning används stora energimängder och inom industrin har det under många år funnits en strävan att energieffektivisera processer och att tillvarata spillenergi, bland annat genom värmeåtervinning. Valmet Tissue Technology Center i Karlstad har idag en pilotmaskinen utan värmeåtervinningssystem. Den här undersökningen gjordes i syfte att ta reda på hur stor återvinningspotentialen är för värmeväxling i pilotmaskinens torkpartier, bestående av Yankeekåpan och TAD-cylindrarna. Tre maskinkoncept undersöktes: DCT®, NTT™ och TAD. Entalpi och effekt i utgående torkluft bestämdes utifrån dess massflöde, temperatur och fukthalt för respektive koncept och torkparti. För att beräkna återvinningspotential i luftflödena undersöktes effektbehov för avsättningsalternativ bestående av förvärmning av förbränningsluft och make-up air, uppvärmning av radiatorvatten samt ånggenerering med Waste Heat Steam Generator. Effekt- och energimässig återvinningspotential beräknades dels teoretiskt och dels reellt med simuleringsprogram för befintliga produkter. Ekonomisk besparing från minskad energianvändning samt investeringskostnad för respektive avsättningsalternativ och torkparti beräknades. Paybacktid användes som mått på ekonomisk lönsamhet. Utöver ovanstående undersöktes om det finns ett samband mellan aktivitet på pilotmaskinen och effekttopparna för fjärrvärmeanvändning i den aktuella byggnaden. Störst entalpi har utgående torkluftsflöden från Yankeekåpan vid DCT-körning följt av NTT-körning. Den största effektmässiga återvinningspotentialen för luftförvärmning finns i TAD-cylinder 1 men betydande tryckfall uppstår i värmeväxlaren på grund av stora luftflöden. Waste Heat Steam Generator kan inte användas ihop med pilotmaskinen på grund av för låg entalpi och effekt i utgående torkluft. Generellt är den reella återvinningspotentialen vid luftförvärmning mindre än den teoretiskt beräknade. Totalt innebär värmeväxling från Yankeekåpan den största årliga energibesparingen vid luftförvärmning. Reell energibesparing vid luftförvärmning i Yankeekåpan är 55 MWh per år vilket motsvarar 4 300 kg gasol. För uppvärmning av radiatorvatten finns den största effekt- och energimässiga återvinningspotentialen vid värmeväxling i Yankeekåpan under DCT-körning följt av NTT-körning. TAD-körning innebär en mindre återvinningspotential vid värmeväxling både i Yankeekåpan och TAD-cylindrarna. Totalt innebär värmeväxling från Yankeekåpan den största årliga energibesparingen vid uppvärmning av radiatorvatten. Reell energibesparing vid uppvärmning av radiatorvatten med torkluft från Yankeekåpan är 153 MWh fjärrvärme per år. Årlig kostnadsbesparing vid luftförvärmning är 43 000 SEK och vid uppvärmning av radiatorvatten 63 400 SEK. Paybacktid för investering i luftförvärmning är 2,6 år och för uppvärmning av radiatorvatten 4,4 år. Ett samband mellan att pilotmaskinen körs och hög fjärrvärmeförbrukning finns, dock är det rutinförändringar kring lokalventilering under körning som främst kan bidra till att sänka de högsta effekttopparna. / There are great demands on industrial companies today to be environmentally responsible and resource-efficient. Within the paper and tissue industry a lot of energy is being used in the processes and since many years there’s been a development towards a more efficient energy use, for example by recovery of waste heat. Valmet Tissue Technology Center in Karlstad, Sweden, has a pilot tissue machine without a waste heat recovery system. This thesis was carried out to investigate the waste heat recovery potential of the pilot machine’s drying sections, being the Yankee hood and TAD cylinders. Three different concepts of the machine were studied: DCT®, NTT™ and TAD. The enthalpy and heat flows of the exhaust air from the drying sections were calculated by the air’s mass flow, temperature and humidity. To calculate the heat recovery potential the heat demand for pre-heating combustion and make-up air, heating radiator water and generating steam by using a Waste Heat Steam Generator was investigated. The heat recovery potential was calculated theoretically but also simulated using programs for real heat exchangers. Economic savings from reduced energy use and investment costs was used to calculate the payback time for each investment alternative. As a separate task the maximum district heating loads in the facility of the pilot machine was cross checked with the pilot machine activity, to clarify any relationship between them. The largest enthalpy was found to be in the exhaust air from the Yankee hood when running the DCT concept followed by the NTT concept. However, the largest heat flow is in the exhaust air from the first TAD cylinder. The air from the first TAD cylinder meant the largest heat recovery potential but caused big pressure drops in the heat exchanger. The Waste Heat Steam Generator cannot be used together with the pilot machine due to too low enthalpy and heat flow in the exhaust air from the drying sections. In general the real heat recovery potential when pre-heating combustion and make-up air is smaller than the theoretical potential. In total, heat exchange using exhaust air from the Yankee hood means the largest energy saving when pre-heating air. The real energy saving when pre-heating air using outgoing air from the Yankee hood is 55 MWh per year, meaning 4 300 kg of propane. The largest potential for heating radiator water occurs when using exhaust air from the Yankee hood when running the DCT concept followed by the NTT concept. The TAD concept means smaller heat recovery potential regardless of air from the Yankee hood or TAD cylinders is being used. In total, heat exchange using outgoing air from the Yankee hood means the largest yearly energy saving when heating radiator water, the real energy saving in district heating being 153 MWh per year. The economic saving when pre-heating air is 43 000 SEK per year and when heating radiator water 63 400 SEK per year. The payback time when investing in pre-heating air is 2,6 years and when heating radiator water 4,4 years. A relationship between running the pilot machine and big loads of district heating use can be seen. However, changing the routines of ventilation in the machine hall during trial days would probably be the easiest way to reduce the maximum loads.

Med hjälp av systembilder, PLC-kod, studiebesök och intervjuer konstruerades en funktionsbeskrivning för styrning och hantering av ett värmeåtervinningssystem vid namn Avgaspannan, på Volvo GTOs, f.d. Powertrain, anläggning i Skövde. Syftet bakom examensarbetet var att skapa en funktions-beskrivning som skulle vara ett stöd för nuvarande, men även blivande personal. Eftersom det i dags-läget inte finns någon dokumentation kring styrningen av systemet. Tanken bakom arbetet är att med hjälp av redan existerande programkod och systembilder skapa en väldokumenterad och välfylld funktionsbeskrivning. För att komplettera dokumentet till största möjliga mån, genomfördes även studiebesök för att se systemet i verkligheten samt genomfördes även intervjuer för att erhålla information och kommentarer från driftpersonalen. Värmeåtervinningssystemet utvinner värmen från producerade avgaser från smältugnarna i Gjuteriet. Värmen som utvinns värmer i sin tur upp fjärrvärmevatten som sedan pumpas ut på Skövde kommuns Fjärrvärmenät för att under vinterhalvåret hjälpa till och förse Skövde med värme. De steg och moment som utfördes under arbetets gång har resulterat i ett godkänt dokument hos aktörerna och de är nöjda med arbetet. För att kunna nå det färdiga resultatet genomfördes studier kring och i PLC-programmet samt systembilder, det utfördes även studiebesök och intervjuer. Dessa mo-ment var byggstenarna för att kunna få ett godkänt resultat. / With the aid of system images, PLC-code, studies at the facility and interviews, a functional description was designed for the control and management of a waste heat boiler named Avgaspannan, at Volvo GTOs, Powertrain, plant in Skövde. The purpose of the thesis was to create a functional description that would support current, but also prospective staff. Since there is currently, no documentation regarding the control of the system. The idea behind the work is to create a well-documented and well-filled function description by using already existing program-code and system images. To supplement the document to the greatest extent possible, studies at the facility and the real system was made. Interviews were also conducted to obtain information and comments from the operating staff.The heat recovery system extracts the heat from produced exhaust gases from the smelters in the foundry. The heat that is extracted, will heat up the district heating water, which is then pumped out on Skövde municipality’s heating network in order to help and provide Skövde with heat during the winter. The steps performed during the course of the work have resulted in an approved document by the actors and they are satisfied with the work. To be able to achieve the final result, studies were conducted on and in the PLC-code and system images, as well as study visits and interviews. These elements were the building blocks for being able to get an approved result.

Potentialen för nyttiggörandet av spillvärme hos två metallindustrier utvärderas. Det ena företaget härdar stål med vatten och det andra gjuter aluminiumtackor i vattenbad och sprayar även vatten som bildar fuktig luft. Vattnet, ej det sprayade, kyls sedan i kyltorn för att kunna återanvändas i processerna. Sankey-diagram för båda företagen presenteras för att tydligt presentera energiflödena i processerna. Värmeåtervinningsförslag presenteras med gasolkostnadsbesparings exempel. Investeringskostnader och återbetalningstider har ej utvärderats. Teoridelen och metoden är användbar för den som vill utvärdera potentialen för värmeåtervinning hos industrier som använder vatten i olika typer av kylprocesser. I teorin presenteras elproduktions metoder för låga temperaturer, dock ansågs inget av företagen vara lämpliga för elproduktion. Värmeåtervinningsförslagen som presenteras innefattar golvvärme, luftvärmare, fjärrvärmeintegrering och värmelager.

Methods for reduced energy consumption is a current subject due to ongoing climate changes and therefore a current matter in the global discussion. Policies and propositions are developed on both a global and national level, in order to decrease the overall consumption. The global target which embraces the reduction in use of energy affects industries and buildings to practice a more energy efficient usage, as well as developing efficient systems for heat recovery. This project investigates the potential in energy efficiency in a food manufacturing facility who serves Västerås central hospital. The buildings use of energy is calculated as an active heat balance, including ventilation, transmission and unintended ventilation losses. The active heat balance is used as a reference where the percentual energy reduction followed by application of the energy efficient suggestions is calculated, hence, suggestions for energy efficient actions are presented. Energy efficient and economical sustainable suggestions are developed along with the obtained information from visits on-site as well as through discussions with the operating manager. The suggestions contain operation improvements, renovation and upgrades of technical devices. The main focus of the study addressed the buildings heat consumption in both cooled and heated areas.  The suggestions were presented in terms of life cycle cost analysis to display whether the improvement is economical sustainable. It is shown that if all of the suggested improvements are implemented, the reduced energy use for heating could be decreased by 24.5 %. The economic analysis shows that all suggested actions are more cost efficient than the current building and hence considered as profitable. Discussion regarding the proposed actions and the locally developed claim for energy efficient actions were reviewed. The discussion illustrates advantages and disadvantages regarding different kind of heat exchangers as well as how additional isolation in walls affects the buildings heat balance. In conclusion, the results of the suggested actions are discussed and however they are appropriate for the investigated facility.