In the paper, there are presented issues related to the ice rink venues. These widely known objects,all around the world,are one of the most complex types of the public buildings. It is caused mainly by the thermal conditions, which prevails in such objects but also energy demand needed for operational processes. Range of indoor temperatures may vary from -5oC in place of ice pad and close to it, up to +20oC in dressing rooms, offices or tribunes for the spectators. Like any other buildings, the same ice rink venues should meet the conditions and provide proper indoor environmental quality (IEQ) for every user of the object. It is mainly performed by the appliance of the newest technology, which is taking care and control aspects like: temperature, relative humidity, energy usage, lighting etc. In this document, there are presented 5 ice rink facilities,which were taken into account, in order to check if there are providing comfortable and proper conditions indoors. All the investigated halls were in the City of Stockholm. In order to obtain require data, some professional tools were used including infrared camera and moisture meter. The registered data was including the average temperature of the indoor air and level of relative humidity. Based on this data, the dew point temperature has been calculated. Another aspect of the work was carrying out simulations of the typical ice rink wall construction and finding the best possible placement for the vapour barrier. In these case, the simulation had been performed in the different cities located in Sweden. Function of this layer is mainly to inhibit the migration of the water vapor and to protect the thermal insulation layer from dampness. However, installed in wrong place in the wall composition may give rise to serious problems related to moisture and humidity. By using WUFI software, it was possible to present hygrothermal conditions like: relative humidity, dew point temperature and water content of the individual component of designed wallin relation to different placement of damp proofing material.

The average energy consumption of one ice rink is around 1000MWh/year, which approximately69% is occupied by the refrigeration unit and heating demand. With the aim of decreasing theenergy consumption, a new concept of refrigeration system with CO2 as a refrigerant has beendeveloped and it is promising to become a high potential next generation for refrigeration systemin ice rink.This thesis is to evaluate a new refrigerant application in ice rink refrigeration system underthree different aspects; energy performance, heat recovery potential and economic efficiency. Inorder to make this evaluation, three main tasks are executed. Firstly, literature review and marketstatistic are processed to give a general picture of the CO2 development as a refrigerant. Secondly, asoftware Pack Calculation II is used for the simulations of CO2 refrigeration system and traditionalice rink refrigeration system. Älta ice rink located in Sweden, is chosen as a reference case forsimulation’s input data. The simulation results is to compare these system in terms of energyperformance and heat recovery potential. Finally, life cycle cost of these systems is calculated toinvestigate the economic benefits from this new application.Results from this study show good benefits of the new CO2 application in ice rink. Fromthe market statistics, CO2 has become a successful refrigerant in supermarket food and beverageindustry with 1331 CO2 refrigeration system installed until 2011 in Europe (Shecco2012). In icerink industry, 24 ice rinks have been applied CO2 in the second cycle of refrigeration system; oneice rink in Canada applied a refrigeration system with only CO2 in the first cycle and the distributionsystem.From the simulation’s result, CO2 full system has been proven as the most efficiency sys-tem with the lowest energy consumption (30% lower than NH3/Brine system and 46% lower thanCO2/Brine system) and the highest COP (6.4 in comparison with 4.9 of NH3/Brine system and4.37 of CO2/Brine system). Regarding heat recovery potential, CO2 full system has highest energysaving in comparison with the other two systems.Due to lower energy cost and service cost, the life cycle cost of CO2 full system is loweraround 13% than the traditional NH3/Brine system, furthermore, the component cost of CO2 sys-tem is promising to decrease in the next years thanks to the rapid development of this market insupermarket industry.To conclude, CO2 full system has high potential to become a next generation of refrigerationsystem in ice rink, however, because of its transcritical working, this application can be restrictedin the regions of warm climate.

Ice rinks are among the most energy intensive public buildings in developed and developing countries. According to a research on Swedish ice rinks; a typical ice rink consumes approximately 1185 MWh/year which leads to more than 300 GWh/year for the 342 Swedish indoor ice rinks. The refrigeration system is usually the largest consumer by 43% average share of the total energy consumption.  To decrease the refrigeration system energy demand, there are a variety of energy efficiency techniques known and available but the key to select the best ones is finding the major heat loads on the ice sheet and refrigeration system, which is unique for each ice rink. To fulfil this objective and in addition to review literature, this study has two main approaches. The first approach is to measure and evaluate the performance of the refrigeration system in two ice rinks, called Norrtälje and Älta. The estimated cooling capacity is approximately equal to the total heat load on the ice plus the heat gains in the distribution system. This goal has been accomplished by using a performance analyser called “ClimaCheck” which is based on an “internal method” because it uses the compressor as an internal mass flow meter and consequently, there is no need for an external one. The refrigerant mass flow rate is calculated by an energy balance over the compressor. By knowing the mass flow, enthalpy of the refrigerant, etc. the cooling capacity and COP of the system can be calculated. While the total heat load is known by the first approach, the second approach tries to discover different heat loads shares by analytical modelling. The measured physical and thermodynamical parameters plus the ice rink geometrical characteristics are input to the heat transfer correlations to estimate the heat load magnitude. The results of the measurements show that the total energy consumption in Norrtälje is about two third of Älta. The main reasons for this less energy consumption are smarter control systems for compressors and pumps, better ventilation distribution design and 1°C-2°C higher ice temperature.      Analytical modelling for a sample day has estimated that about 84% of the total heat loads is originated from the heat loads on ice sheet while the distribution system causes the remaining 16%. Moreover, calculations show that convection plus small portion of condensation (altogether 36%), radiation (23%), ice resurfacing (14%) and lighting (7%) are the largest heat loads in winter while in summer condensation is another significant heat load (10%). Comparing two six-hour periods, one without ice resurfacing and four resurfacings in the second one, 30% more cooling demand has been calculated for the second period. Furthermore, it has been shown that the evaporator to brine is the contributor for 66% of the heat transfer resistances from ice to evaporator while brine to bottom ice and bottom to top ice accounts for 27% and 7% respectively. To conclude, a parallel “performance analysis of the refrigeration system” and “heat loads estimation” proves to be a useful tool for adopting proper design and control for energy efficient operation. / Stoppsladd financed by Swedish Energy Agency (Energimyndigheten) and Swedish Ice Hockey Association

Currently 341 ice rinks are in operation in Sweden with an estimated total energy consumption of 384 GWh/year. As it has been revealed in previous studies, most of the ice arenas are constructed and/or not operated efficiently. Thus it is considerable energy saving potential, which could be achieved in this area. The potential is even more significant if one can consider the savings in the ice rinks all over the world. This report is an in-depth study, which aims at analysing the Swedish ice rinks energy consumption and estimation of the corresponding energy saving potential. The report analyses the energy statistics obtained through the Stoppsladd study, which includes the ice rinks inventory, data collection and compilation of energy relevant data for 100 ice rinks located in Sweden. The inventory has revealed a number of important statistical figures, such as total energy consumption average in total (estimated to be 1,137 MWh/year) and for different ice arenas categories in particular. Relevant specific energy consumption values as well as a number of other important figures are also provided in the paper, thus giving an idea on the way to minimise energy consumption at each specific ice rink. The results are additionally supported by statistical multifactor regression analysis, which resulted in a relation between the ice rink’s total energy consumption and some known factors values affecting it. Two in-depth studies fulfil the Stoppsladd project by analysing water quality and ice quality effect on the ice rink’s energy consumption and investigation of the static and dynamic heat flow distribution in ice rink slab. A static heat flow distribution model of an ice rink evaluated the effect of concrete  with different properties on temperature and heat flow distribution within an ice rink floor slab. The study proves that the ice rink refrigeration system COP2 could be increased with 3.5 % just implementing new high thermal conductivity concrete layer into the conventional concrete ice rink floor. The static analysis results were further completed with dynamic analysis, which adequately reflects the thermodynamic response of the concrete ice rink floor to a varying heat load. As a result, the thesis represents a holistic approach to the ice rink energy efficiency increase problem and provides a good basis for further studies in relevant areas. It is proved that modified concrete allowing higher (efficient) secondary refrigerant tempera­tures and also provides better response to change in heat load to the system. / Stoppslad

Title: Analysis of the ice hockey stadium in Mělník and the proposal of marketing plan Objectives: The aim of this work is to elaborate analyzes of the state of the ice hockey stadium in Melnik and to create a proposal of a marketing plan for the stadium. The plan should serve to a more efficient functioning of the entire ice rink in the following years. Methods: The work analyzes years 2011-2013 where it focuses on the utilization of the ice surface, public skating hours and skating schools and analysis revenues and expenditures in the same period. Interviewing visitors, and competitive analysis of stadiums around Melnik were carried out. All values obtained from analyzes were subsequently compared with the national average values obtained from KPMG research. Results: The analyses identified the potential in greater efficiency of utilization of the ice surface and rental of advertising space. When comparing public financing is Melnik's stadium to the national average in the same size cities it turns out that Melnik's stadium is underfunded. The whole proposal of the marketing plan was compiled into 4 main sections aimed at attracting potential sponsors, increased use of ice rinks in the months of September to March, an increase in attendance of public skating and skating schools in the same...

Sweden has 350 ice rinks in operation which annually use approximately 1000 MWh each. Therefrigeration system usually accounts for about 43 % of the total energy consumption which is the largestshare of the major energy systems. Besides improving the facilities one-by-one, it is important todistinguish common features that will indicate the potential energy saving possibilities for all ice rinks.More than 97 % of the Swedish ice rinks use indirect refrigeration systems with a secondary fluid.Moreover, the thermo-physical properties of secondary fluids directly impact the heat transfer andpressure drop. Thus, assessing and quantifying their influence on the refrigeration system performance isimportant while estimating the energy saving potential for the ice rinks.A theoretical model as well as two case studies focusing on the importance of the secondary fluid choiceare investigated. The theoretical model calculations are performed assuming the steady-state conditionsand considering a fixed ice rink design independently on the secondary fluid type. Hence, they can becompared on the same basis. According to this theoretical model, the refrigeration efficiency rankingstarting from the best to the worst for secondary fluid is: ammonia; potassium formate; calcium chloride;potassium acetate; ethylene glycol; ethyl alcohol; and propylene glycol. Secondary fluids can be ranked inexactly the same order starting from the lowest to the highest value in terms of the dynamic viscosity. Itwas shown that potassium formate has the best heat transfer properties while ammonia leads to the lowestpressure drops and pumping power. Propylene glycol shows the worst features in both cases. Ammoniaand potassium formate show respectively 5% and 3% higher COP than calcium chloride for typical heatloads of 150 kW. When controlling the pump over a temperature difference ΔT, the existence of theoptimum pump control or optimum flow was highlighted. For common heat loads of 150 kW thisoptimum pump control ΔT is around 2,5 K for calcium chloride while it is around 2 K for ammonia. It isshown that the secondary fluids having laminar flow in the ice rink floor pipes have a larger share in theconvection heat transfer resistance (~20-25 %) than the secondary fluids experiencing turbulent flow (~3%).One of the case studies shows a potential energy saving of 12 % for the refrigeration system whenincreasing the freezing point of the secondary fluid. An energy saving of 10,8 MWh per year was foundfor each temperature degree increase in the secondary fluid freezing point.

Indoor ice rinks use 1091 MWh per annum for ice hockey based on statistics from over 100 Swedish ice rinks (Stoppsladd, 2011).The refrigeration system contributes 35 to75%( (Rogstam, 2010) of total energy usage in ice rinks with average value of 43% (Stoppsladd, 2010) for indoor to 75% for outdoor ice rinks. The basic aim of project is to reduce energy consumption in Swedish ice rinks and scope is for indoor and outdoor ice rinks in cold and mild summer climatic conditions like Sweden. To achieve target of energy reduction in ice rinks actual heat loads on outdoor bandy ice rink are being estimated along with performance analysis of refrigeration machine. The refrigeration system, heat loads on ice surface and their correlation is studied and analyzed in detail for Norrtälje Outdoor bandy ice rink for four warm days and whole season 2010-2011. The tricky and significant task of validation of input climate data for accurate heat loads calculations is completed with Swedish Metrological & Hydrological (SMHI) climate model data, correlations and related web based geographical data. The heat loads (conductive, convective and radiant) on outdoor bandy ice rink are calculated through thermodynamic relations with validated input climate data and measurements where as refrigeration system performance is monitored and analyzed with ClimaCheck(CC) instrumentation. The average cooling capacity is calculated for four warm days by CC internal method and actual cooling energy produced is obtained by practically assumed COP of system with aid of MYCOM compressor software. The cooling capacity and heat loads on ice surface are compared and analyzed considering energy usage affecting parameters and weather parameters like temperature, wind speed, relative humidity and solar load. The convection and condensation are contributing 75%, radiation 18%, ice resurfacing 4% and ground and header heat gain 3% to total heat loads on ice sheet for whole season. The deviation between total cooling energy produced by refrigeration machine and total heat load energy is found 19% and 27% for four warm days and whole season 2010-2011.The deviation is due to overestimation of heat losses from compressor’s body, compressor’s on and off operations, overestimated radiation heat load due to unmeasured negative radiation and lack of actual ice resurfacing heat load evaluation. The developed model in MS Excel allows comparison of field climate data with SMHI model data, indoor and outdoor ice rinks in terms of predicted energy usage by refrigeration system and in total and acts as decision tool to choose for building an indoor/outdoor ice rink.

In Sweden there are about 350 ice rinks in operation today which consume approximately 300 GWh per year. The average energy consumption for a Swedish ice rink is approximately 1000 MWh per year. Ice rink dose not only consume energy it also rejects heat. The rejected heat comes from the refrigeration system that cools down the ice floor. The refrigeration system rejects heat around 700 to 1000 MWh per season. The reason for this study is because of the rejected heat which leads to the question how the rejected heat can be used.The object is to find a heat pump concept that can use the rejected heat or another heat source in an ice rink. Three different heat pump concepts were evaluated. The first heat pump concept use the ice floor as a heat source (called BHP), the second concept use the rejected heat as a heat source (called CHP) and the third concept use the rejected heat to charge an energy storage (called GHP).To accomplish the objective a heat analysis of two ice rinks were made to be able to simulate the heat pump concepts. With the simulation results a life cycle cost was made for a better evaluation. The results from the heat analysis were used for simulating the heat pump concepts. The two ice rinks that were analyzed were Järfälla ice rink and Älta ice rink. The main heat source the two ice rinks uses today is district heating and electricity. Järfälla only use district heating (DH) as a heat source and Älta ice rink use recovery heat, electricity and district heating.The heat analysis of the two the ice rinks showed that the highest district heating consumer was the domestic hot water at 47% of the DH followed by the dehumidifier at 32% of the DH and last the space heating at 22% of the DH. This shows how the heat is used in a general ice rink in Sweden. The temperature levels for the dehumidifier is around 65 °C (only DH part), the domestic hot water at 55 °C and last the space heating at 20 °C. However the heat demand for the ice rinks resulted in 443 MWh for Järfälla and 192 MWh for Älta. To know the size of the heat pump used for the heat pump concepts a heat profile for the ice rinks were made. The result of heat profiles lead to a heat pump size of 105 kW in Järfälla and 45 kW in Älta. The rejected heat for one season in Järfälla is 1000 MWh and 780 MWh in Älta.With the results from the heat analysis the evaluation the heat pump concepts was possible. The COP1 for the CHP resulted at 3,8 and the COP1 for the GHP was assumed to be the same as for the CHP. The COP1 calculations for the BHP concept resulted at 2,5. COP was calculated with collected data from the respective ice rinks refrigeration system. The simulations results were that the BHP and the CHP concept could fulfill the heat demand up to around 79% and the GHP up to around 84% in both ice rinks. The rest of the heat demand is heated with supplementary heat. The life cycle cost (LCC) showed that the CHP concept had the lowest cost followed by the GHP concept. The BHP concept had the highest LCC, because of the low COP. The LCC model dos not include the running cost, the maintenance cost and the energy tariffs for the district heating.The recommended solution is the GHP concept. This is because it is a good investment for the future since other buildings can be connected to the energy storage. The GHP concept is also the solution that fulfills the heat demand best and has the lowest annual energy cost.

This project aimed to investigate the existence of thermal surplus energy from the ice rinks at Gränby Sports Field, Uppsala. Furthermore, a secondary goal was to suggest a distribution system for sharing the potential surplus energy. To fulfil the purpose, each ice rink was modelled in the software IDA ICE. The following ice rinks were considered: buildings A and B, building C and the bandy arena. Data regarding the total heat and cold consumption for each building was collected from the owner, Uppsala kommun Sport- och rekreationsfastigheter AB, and was used to validate the simulation results from the building models. The results from IDA ICE were presented in graphs that illustrate each ice rink’s total heat and cold consumption, surplus energy and energy balance. However, the results from the models in IDA ICE were not validated within a deviation of a maximum of 10% when compared to the data from Uppsala kommun Sport- och rekreationsfastigheter AB. Hence, the results were analyzed on a general level, which showed that there was a greater need for heating during wintertime, with certain peaks during the coldest months, whereas the cooling is maintained at a relatively stable level throughout the year, but with a slightly greater need in the summer. Further on, there was an identified surplus energy from the ice rinks, in terms of waste heat from the refrigeration systems. During the summer there was a greater amount of surplus heat generated, caused by the greater cooling demand. Due to not being able to validate the models, complementary calculations of the yearly surplus heat were made with data from Uppsala kommun Sport- och rekreationsfastigheter AB. The surplus heat was 1 200 MWh for buildings A and B, 497 MWh for building C and 1 492 MWh for the bandy arena. No surplus cold was identified within the ice rinks. The suggested solution for sharing the surplus energy is to implement seasonal thermal storage, due to the similar characteristics in heating and cooling demand for the ice rinks. The stored surplus energy could cover the ice rink’s peaks in heating demand during winter, which is an energy-efficient way would reduce purchased heat from the district heating grid. For further studies, it is of great interest to identify the possibilities of implementing a distribution system similar to the fifth generation district heating as well as seasonal storage, to possibly enable a direct share of energy between all the buildings within the sports field.

The transition from fluorinated gases to natural refrigerants could be key to reducing the impacts of climate change. Ice rinks are energy-intensive buildings, with large heating and cooling demands. The pumping power required to move the secondary refrigerant typically accounts for a sizable amount of the energy use of the refrigeration system. The use of aqua ammonia as a secondary fluid shows promising results, with pumping power use of about half that required of ethylene glycol, environmental friendliness, and low corrosivity to steel components. Aquaammonia is still novel but is currently in usein 34 Swedish ice rinks. This thesis addresses questions regarding evaporation rates, performance, material compatibility, safety, and regulations of aqua ammonia in ice rink systems. Laboratory tests were performed to assess aqua ammonia evaporation rates during storage and operations. Long-duration concentration change, in well-sealed and well-stored containers, indicated low levels of evaporation for all tested concentrations samples. Short-term concentration in open-air conditions, indicated rapid rates of evaporation, with nearly full evaporation of all ammonia concentration occurring within only 90seconds of open-air exposure. Testing of sample-mixtures containing contamination by substances aquaammonia was likely to encounter during retrofit replacement situations determined that aquaammonia and calcium chloride produce flakey sedimentation. Additionally, lower concentrations of aquaammonia are slightly more prone to becoming basic when mixed with the tested substances, such as calcium chloride. Historical data of systems operating with aquaammonia were analyzed for energy performance. While pumping requirements typically account for 10-20% of the energy for refrigeration, the pumps of the rinks studied with aqua ammonia accounted for only 1.2 to 4.2%. However, data availability and system configuration anomalies suggest additional analyses are required. Furthermore, best operating, maintenance, and safety practices were analyzed and global regulatory restrictions were examined. Surveying of manufacturer material compatibility information found copper and brass to be incompatible with aqua ammonia, while steel and carbon steel are recommended. Various plastics were addressed by the manufacturers, notably PVC was found to be acceptable for use with aqua ammonia. A cost comparison between aqua ammonia and calcium chloride found aqua ammonia to require less expensive equipment. Finally, aqua ammoniawas determined to fall outside of the classification of refrigerants in several international refrigeration codes. Various additional safety regulations guiding personal protective equipment, exposure times, transportation, storage, and disposal regulations were catalogued as part of this work. In summary, aqua ammoniawas found to be a safe substance with performance that matches theoretical energy savings. Pumping requirements were reduced from 10-20% to approximately 1-5% of overall refrigeration system energy use. Necessary safety precautions were found to be much less stringent than high concentrations of ammonia and aqua ammonia was ascertained to fall outside of refrigeration codes in Europe, Canada, and the United States of America. / Övergången från fluorerade gaser till naturliga köldmedier kan vara nyckeln till att minska effekterna av klimatförändringen. Isbanor är energikrävande byggnader med stora värme-och kylbehov. Den pumpeffekt som krävs för att pumpa köldbärare står vanligtvis för en stor mängd energianvändning i kylsystemet. Användningen av ammoniakvatten som köldbärare visar lovande resultat, med användning av pumpeffekt på ungefär hälften som krävs av etylenglykol, miljövänlighet och låg korrosion för stålkomponenter. Ammoniakvattenär fortfarande ny men används för närvarande i 34 svenska isbanor. Detta exjobb behandlar frågor om avdunstningshastigheter, energiprestanda, materialkompatibilitet, säkerhet och föreskrifter för ammoniakvatten i isbanasystem. Laboratorietester utfördes för att bedöma avdunstningshastigheter för ammoniakvatten under lagring och drift. Långvarig koncentrationsförändring, i väl tillslutna och välförvarade behållare, indikerade låga nivåer av avdunstning för alla testade koncentrationsprover. En kortvarig koncentration under friluftsförhållanden indikerade snabba avdunstningshastigheter, med nästan full avdunstning av all ammoniakkoncentration inom endast 90 sekunder efter exponering. Testning av olika ammoniakvatten lösningar som innehåller föroreningar skulle sannolikt påträffas vid byte av köldbärare. Dessutom är lägre koncentrationer av ammoniakvatten lite mer benägna att bli basiska när de blandas med de testade ämnena. Historiska data för system som arbetar med ammoniakvatten analyserades med avseende på energiprestanda. Medan pumpeffekten vanligtvis står för 10-20% av kylenergin, pumparna för de studerade isbanorna med ammoniakvatten behövde bara för 1,2 till 4,2%av kylenergi. Datatillgänglighet och systemkonfigurationsavvikelser föreslår dock att ytterligare analyser krävs. Dessutom analyserades bästa metoder för drift, underhållning och säkerhet och globala regleringsbegränsningar. Kartläggning av tillverkarens materialkompatibilitetsinformation visade att koppar och mässing var oförenliga med ammoniakvatten, medan stål och kolstål rekommenderas. Olika plast och packning materialbehandlades, särskilt PVC var acceptabelt för användning med ammoniakvatten. En kostnadsjämförelse mellan ammoniakvatten och kalciumklorid köldbärare visade att ammoniakvatten krävde billigare utrustning. Slutligen visades det att ammoniakvatten faller utanför klassificeringen av köldmedier i flera internationella kylnormer. Olika ytterligare säkerhetsreglersom styr personlig skyddsutrustning, exponeringstider, transport, lagring och bortskaffande föreskrifter katalogiserades som en del av detta arbete. Sammanfattningsvis visade ammoniakvatten vara ett säkert ämne med prestanda som matchar teoretiska energibesparingar. Pumpeffekten minskade mellan 10-20% och 1-5% av den totala energianvändningen i kylsystemet. Nödvändiga säkerhetsåtgärder visade sig vara mycket mindre stränga än att höga koncentrationer av ammoniak och ammoniakvatten konstaterades falla utanför kylnormeri Europa, Kanada och USA.