Energy efficiency is important both to reduce costs and to reduce greenhouse gas emissions in the atmosphere. Reducing costs will also help maintain business competitiveness. Scania in Södertälje is a company where the optimization of energy use is an ongoing and continual process. One area with potential to make energy and cost savings is the effectiveness of the ventilation systems in offices and industrial premises at Scania. During the summer months an increased demand for cooling occurs, leading to increased ventilation and a peak in district cooling system usage. Sorptive cooling is a technology where the supplied air is cooled by applying external heat. This technique involves a reduction in electricity consumption compared to electrically-powered cooling machines and does not affect the district cooling system usage. It was therefore of interest to investigate if sorptive cooling would be an energy efficient and viable solution for Scania in the future. This investigation shows that sorptive cooling requires more power than a conventional ventilation system. Despite the fact that Scania has access to free heat during the summer months, the study shows that sorptive cooling would not be economically viable to install in the industrial premises, where no cooling systems currently exist. However, compared to an electrically-powered cooling machine, sorptive cooling is anyway more energy efficient. The conclusion is that sorptive cooling is a viable solution for the offices, but not for the industrial premises at Scania in Södertälje

Cooling down the indoor air can be done in several ways. One way is desiccantcooling which will be used at the Stockholm Arena. This method is used in airhandling units that use temperature changes and moisture fluctuations in the air. Oneof the steps is to add heat during the cooling process in order to reduce the relativehumidity of the exhaust air. The air passes thru an adsorptions rotor which thenabsorbs moisture from the supply air. This results in the closing stages that the supplyair temperature drops when hydrating and the result is a cooler indoor temperaturethan the outdoor. This report is a result of a diploma work in building construction at UppsalaUniversity and is written as a guide for the Stockholm Arena to reduce theconsumption of purchased thermal energy, with the aim of producing its own energy.This is reported from a technical perspective, focusing at the design of a propersystem. Heat energy is today planned to be brought from district heating. It couldthou be replaced by other alternatives such as solar panels. To determine this, itinvestigates whether and to what degree solar panels can replace the district heat atthe cooling process of the indoor air from a technical perspective. This has beenimplemented with literature studies and interviews and further on calculations ofenergy but also financially by the annuity method. The case is focused on the summer conditions when the sorptive refrigeration willbe used. According to that calculations and assumptions have been made for probableenergy consumption and production. There after the investment costs weredetermined. The results gave that flat glazed solar collectors had a lower cost based on theenergy production but it required a much larger area than the vacuum solarcollectors. Based on the investment cost, vacuum solar collectors would be lesseconomi-cally significant. Further analysis showed that the solar panels took up almost the same amount ofarea whether of choosing them to stand free or be placed right on the roof. Theinvestigations of the operating temperature of the heating coil gained 60 degreesCelsius to optimize the performance. The size of the storage tank should not exceed3 cubic meters to obtain adequate energy changes. Solar energy is added to the tankat an external heat exchanger. At times when the heat input from the solar panels islower than required the district heat is the most appropriate kind to provide externalheat. This heat is given to the hot water slope leaving the tanks so it won’t disrupt theenergy output from the solar panels. In converted case where the production of heatis greater than required the heat energy can be used for hot water production.

Titel: Sorptionsteknik – Kylteknik.– En studie i kylteknik i kommersiella lokalerSyfte: Syftet med detta arbete är att undersöka och utreda om sorptiv kyla är ettekonomiskt bättre alternativ än fjärrkyla och kylmaskiner i kommersiellalokaler.Metod: Arbetet bygger till största delen på en fallstudie. Både kvalitativa ochkvantitativa metoder har använts. Datainsamlingen har bestått av både primäroch sekundärdata. Informella samtal har förts med tillverkare av olika kylsystemoch med driftpersonal som har hand om driften i byggnaden i fallstudien.Slutsats: Sorptiv kyla är en lönsam, miljövänlig och energieffektiv investering som germervärde för både hyresgäster och fastighetsägare. Det ökar fastighetsvärdet,sänker driftkostnaderna och bidrar till ett behagligt inomhusklimat. / Titel: Desiccant cooling– Refrigeration- A study of refrigeration in commercial buildings.Purpose: The purpose of this study is to investigate and analyze if a desiccant coolingsystem is a better alternative than district cooling or vapor compressorrefrigeration in commercial buildings.Method: This work is based on a case study. Both qualitative and quantitative methodshave been used. The collected data is primary and secondary data. Informalconversations with producers and operators have been conducted.Conclusion: Desiccant cooling is profitable, environmentally friendly and is an efficientenergy investment that gives an additional value for both tenants and propertyowners. It will increase the value of the property, lower operation costs andcontributes to a pleasant indoor environment.

<p>The use of air-conditioning and comfort cooling in offices and stores has been increasing during recent years. Adnot, (2002) reports an increased use in commercial buildings by 200 % from 1990 to 2002. The increase is primarily due to the growing use of electrical equipment generating internal heat. The enhanced public demands of the indoor climate are yet another explanation to the increase. The main cooling method used is mechanical chillers based on vapor compression. Many of these cooling systems are old and will shortly become obsolete which gives the property holder a chance to improve in his cooling system.</p><p>The office building Mercurius 12 in Karlstad operates activities that require comfort cooling. The cooling method used is conventional vapor compression which is distributed by an airborne system. The property consists of two buildings one built in 1939 and one in 1970. The property is 7700 m² and accommodates one apartment, offices and stores. The property is currently housing 190 people.</p><p>The aim of this report is that on a basis of life-cycle costs analyze how a change of cooling methods and cooling needs are connected to the Life-cycle costs of the cooling. The practicability of each change shall also be investigated.</p><p>The calculation of the life-cycle costs and heat surpluses have been made using generally accepted formulas that has been outlined in Excel.</p><p>All of the simulated measures to reduce the building's life-cycle costs in terms of internal heat and solar radiation pays off. The higher energy prices, the greater savings.</p><p>The Cooling tower method is the chilling process that provides the minimum life-cycle costs, both with both air and waterborne distribution system.</p><p>Vapor compression used with today’s energy prices provides comparatively to the other investigated methods a low life-cycle cost. The vapor compression method is however not as good if the energy price would get higher than today.</p>

The use of air-conditioning and comfort cooling in offices and stores has been increasing during recent years. Adnot, (2002) reports an increased use in commercial buildings by 200 % from 1990 to 2002. The increase is primarily due to the growing use of electrical equipment generating internal heat. The enhanced public demands of the indoor climate are yet another explanation to the increase. The main cooling method used is mechanical chillers based on vapor compression. Many of these cooling systems are old and will shortly become obsolete which gives the property holder a chance to improve in his cooling system. The office building Mercurius 12 in Karlstad operates activities that require comfort cooling. The cooling method used is conventional vapor compression which is distributed by an airborne system. The property consists of two buildings one built in 1939 and one in 1970. The property is 7700 m2 and accommodates one apartment, offices and stores. The property is currently housing 190 people. The aim of this report is that on a basis of life-cycle costs analyze how a change of cooling methods and cooling needs are connected to the Life-cycle costs of the cooling. The practicability of each change shall also be investigated. The calculation of the life-cycle costs and heat surpluses have been made using generally accepted formulas that has been outlined in Excel. All of the simulated measures to reduce the building's life-cycle costs in terms of internal heat and solar radiation pays off. The higher energy prices, the greater savings. The Cooling tower method is the chilling process that provides the minimum life-cycle costs, both with both air and waterborne distribution system. Vapor compression used with today’s energy prices provides comparatively to the other investigated methods a low life-cycle cost. The vapor compression method is however not as good if the energy price would get higher than today.

Syftet med detta examensarbete är att värdera och jämföra ett antal utvalda kyltekniker, med huvudfokus på värmedriven kyla. Dels för en specifik befintlig byggnad men även en generell jämförelse som kan ligga till grund för andra projekt. Arbetet är utförti samarbete med ÅF i Borlänge. Den specifika byggnaden som har undersökts är belägen i Borlänge och kyls idag av stadsvatten, och har en kyleffektpå 655kW. Borlänge Energis fjärrvärmenät ligger till grund för samtliga beräkningar och antaganden. Huvudsyftet har varit att jämföra de olika kylteknikerna ur ett ekonomiskt perspektiv, men även snudda vid ett miljöperspektiv. Utöver detta så var syftet att undersöka hur en fjärrvärmeleverantör ska kunna leverera kyla till sin kund, utan att behöva gräva ner nya fjärrkylledningar. De kyltekniker som jämförts i detta arbete är absorptionskyla, adsorptionskyla, sorptiv kyla &amp; eldriven kompressorkyla. För att kunna jämföra de olika teknikerna har den totala livscykelkostnaden beräknas. Investeringskostnader och data har erhållits ifrån leverantörer genom kontakt med kunniga säljare. Driftkostnader har beräknats fram med hjälp av driftdata samt energipriser hos Borlänge Energi. Kostnader för installation, frakt och lyft är inte medräknade i detta arbete. För den befintliga byggnaden visade det sig att den mest kostnadseffektiva lösningen är absorptionskyla, tätt följt av att komplettera befintligt system med frikyla i form utav en kylmedelkylare. Absorptionskylan har väldigt låga driftkostnader under sommarhalvåret, då fjärrvärmepriset är som lägst. Dyrast av teknikerna är adsorptionskyla, tack vare den dyra investeringskostnadenoch dess låga verkningsgrad. Även för den generella jämförelsen visade det sig att den mest kostnadseffektiva lösningen är absorptionskyla, tätt följt av eldriven kompressorkyla. Absorptionskylan har mycket låga driftkostnader, men kompressorkylan har istället en lägre investeringskostnad och mycket bättre verkningsgrad. Om Borlänge Energi skulle sälja fjärrvärmeproducerad kyla under sommaren, så skulle de vid 655kW kyleffekt ha en återbetalningstid avett absorptionskylaggregat på endast 2 år. Skulle de istället ha en kyleffekt på 100kW skulle återbetalningstiden vara ca 5 år. Slutsatser kan dras ifrån detta arbete att byggnader med högre kyleffekt är mer fördelaktiga för värmedriven kyla. / The aim of this thesis is to evaluate and compare a number of selected chilling techniques, with a main focus on heat driven cooling. Mainly for an existing building, but also a more general comparison that can be used as a basis for other projects. This thesis has been carried out in cooperationwith ÅF in Borlänge.The building that has been investigated is located in Borlänge. All calculations and assumptions regarding the district heating network are based on Borlänge Energi’s district heating network. The main purpose has been to compare the different cooling techniques from an economical point of view, but also a slight comparison from an environmental point of view. In addition, the purpose has been to investigate how a district heating supplier can deliver cooling to its customers without having to dig down newdistrict cooling pipes. The cooling techniques compared in this thesis are absorption chillers, adsorption chillers, sorptive cooling and conventional electrical compression chillers. In order to compare the different techniques, the total life cycle cost has been calculated. Investment costs and data have been obtained from skillful salesmen representing variouscompanies. Operating costs have been calculated using data and energy prices from Borlänge Energi. Costs for installation, shipping and lifting are not included in this thesis. The most cost-effective solution for the existing building is to install an absorption chiller, closely followed by complementing the existing cooling system with free cooling. The absorption chillers has very low operating costs during the summer, when the price of the district heating is at its lowest. The most expensive technique are adsorption cooling, due to its expensive investment cost and its low efficiency. For the general comparison, it was found that the most cost-effective solution is absorption chiller as well, closely followed by the conventional compressor chiller. The absorption chillers has much lower operating costs than its competitors, but the compressor chiller has a lower investment cost and a much better efficiency. If Borlänge Energi were to sell district heat-produced cooling during the summerusing an adsorption chiller, they would have a payback time of only approximately 2 years, with a cooling power of 655kW. With a cooling power of 100 kW, the payback time would be approximately 5 years. Conclusions can be drawn from this thesis that buildings with higher cooling demand are better suited for heat-driven cooling.

Det finns tydliga hälsofördelar med en relativ fuktighet på 40–60% inomhus. Trots detta finns det idag inga direktiv på hur man ska styra den relativa fuktigheten inomhus. Många gånger diskuteras det kring avfuktning men i denna rapport tas befuktning upp ur ett hälsoperspektiv.I denna studie har det undersökts huruvida befuktningssystem skulle kunna användas i större utsträckning till fördel för människors hälsa.I rapporten redogörs för olika befuktningmetoder samt deras termofysiska processer - adiabatisk eller isotermisk. Dessutom undersöks vad som händer med energin i luften och vattenångan vid olika temperaturer samt vad olika relativ fuktighet har för hälsomässiga för- och nackdelar.Resultatet visar på att det finns både etablerade befuktningssystem samt ett behov av befuktning. Däremot är efterfrågan av befuktning inte speciellt stor i bostäder och branschen ställer sig negativ till befuktning i ventilationssystem. / There are clear health benefits of having a relative humidity between 40–60% indoors. Despite this, there are currently no directives on what level the relative humidity should be indoors. Today dehumidification is a common matter but this report is about humidification, from a health perspective.In this study, it has been investigated whether humidification could be used to a greater extent, to the benefit of humans’ health.This report describes various humidification methods and their thermophysical processes - adiabatic and isothermal. It is also explained what happens to the energy in the air and water vapor at different temperatures and how the relative humidity affects our health at different levels.The result shows that there is a need for humidification and that there are several technical solutions available today. However, the demand is low and the industry is not very positive to the idea of humidification in ventilation systems.

This thesis is based on comparing two different air-ventilation systems with cooling in a building. Two systems are compared, the first one is FTX with heat pump and a rotating heat exchanger, and the second is a system with sorptive cooling. These systems use different types of energy – electricity and district heating for both cooling and heating. The FTX system (FTX 480) is produced from IV product and the system with sorptive cooling (DCI 3.0) is given from the company Munters. An FTX system recycles heat using a heat exchanger. Sorptive cooling is a technique that lowers the temperature by using district heating which cools the warm air coming from outside. The purpose is to study how effective these systems are looking at the costs of the systems and how they impact the climate. This is done by a life cycle cost analysis and a environmental implant analysis. This thesis is guided and has been given documentation by Statens fastighetsverk. The building that is mentioned in this study is Afrikahuset that is located in Uppsala. Product sheets for the systems have been produced and given by the companies IV product and Munters. Results show that system FTX 480 gives a lower cost and a lower climate effect compared to DCI 3.0 (sorptive cooling). Therefore, FTX 480 has the lowest total cost during the systems lifecycle, provides the lowest energy use on an annual basis and provides the best financial outcome over a 30-year time. In conclusion, a FTX system with heat pump and rotating heat pump is more useful than a system with sorptive cooling. / Examensarbetet jämför två olika ventilationsaggregat med olika metoder för luftburen kyla på en befintlig byggnad. Aggregaten ett från- och tilluftssystem (FTX) med värmepump och roterande värmeväxlare samt ett med Sorptiv kyla. Systemen använder olika energislag – el respektive fjärrvärme för både kyla och eftervärmning. Ett FTX aggregat återvinner värme i första hand med hjälp av en värmeväxlare och värmepump vid låga utetemperaturer, värmepumpen kan sedan användas för att kyla luften sommartid. Sorptiv teknik däremot återvinner även värmen med en värmeväxlare men kyler luften med hjälp av fjärrvärme i sekvens med befuktning och avtorkning. Syftet med arbetet är att undersöka hur ekonomiskt och hållbart dessa system är genom att analysera det ekonomiska utfallet samt klimatpåverkan hos båda systemen genom en livscykelkostnadsanalys och miljöpåverkansanalys. Undersökningen utförs med hjälp och underlag från Statens fastighetsverk. Den befintliga byggnaden är Afrikahuset, en utbildning- och forskningsverksamhet i Uppsala. Produktblad har tagits fram från företagen IV produkt samt Munters. En värdering av el och fjärrvärme resulterar i att en minskad elanvändning bidrar till en mer reducerad klimatpåverkan jämfört med fjärrvärme och att 90 procent av den energi som tillförs är återvunnen energi samt att fjärrvärmen normalt är dyrast. Det finns fördelar med värmedriven kyla då det råder stort värmeöverskott i kraftvärmeverken under sommarperioden vilket är bl.a. som en följd av elproduktionen. Studien visar att ett FTX system med värmepump och roterande värmeväxlare är mer ekonomiskt lönsamt (LCC) och bidrar till en mer positiv miljöpåverkan (LCA). Slutsatsen är att system FTX 480 har lägst totalkostnad under dess livstid, ger lägst klimatpåverkan på årlig basis och ger bäst ekonomiskt utfall unde