Energieffektivisering av Tjustvallens bandybana : En studie om energieffektivisering av kylsystem med en isbana i Gamleby som fallstudie

Sammanfattning: In a world with population growth and a limited amount of resources, it is vital to increase resource usage efficiency in order to ensure a high standard of living for future generations. To achieve this, arrangements aimed towards increasing the energy efficiency and environmental friendliness of new and existing technologies are needed. On behalf of Innovationsverket, an inventor association in Gamleby, this study examines the possibility of making the cooling of an outdoor ice rink in Gamleby more energy and cost efficient. This study uses the ice rink at Tjustvallen in Gamleby as a case study. It is cooled with a compression refrigeration cycle consisting of two compressors that conjoined have a maximum input power of 347 kW. The power is adjusted manually based on current weather conditions. The cooling system uses an average of 580 MWh of electricity, equivalent to an annual cost of 534 000 SEK. The purpose of this study is to survey the current energy usage and to find a correlation between power demand and outside temperature. It also aims towards finding suitable actions to increase the system’s energy efficiency and to evaluate whether implementing these actions increase the system’s economic and ecological sustainability. The study is based on material gathered through literature studies, on site visits and personal contact with specialists on the subject. Calculations of correlation between energy usage and outside temperature are made based on this information after which energy efficiency increasing methods are presented. Calculations that determine whether or not they decrease energy usage and greenhouse gas emissions are performed. Seven profitable methods to increase the energy efficiency are presented. Out of these, changed power adjustment to decrease the usage of low loads and automatic pump power adjustment are recommended to be implemented initially. Installation of a system that makes use of waste heat is the most profitable method, assuming that the heat can be sold to nearby houses. A decrease in ice thickness is recommended as a way to decrease electricity usage without changing the cooling system. Great possibilities for increasing the system’s energy efficiency are found. The methods presented decrease energy usage and greenhouse gas emissions. Therefore it can be concluded that implementation of the presented methods increase the system’s economic and ecological sustainability.