LIVSCYKELKOSTNADSANALYS AV FÖRSLAG PÅ ENERGIEFFEKTIVISERINGAR - TVÅ FASTIGHETER BELÄGNA I UMEÅ

Sammanfattning: This report is a degree project carried out at Rejles AB on behalf of a local real estate company in Umeå, Sweden. The real estate company bought two properties with a total of 95 rental apartments from another company in 2018. The buildings were built in 1991 and have installed new ventilation units in 2015, in other words before the change of ownership. The real estate company has requested confidentiality and therefore the properties will be named Property A and Property B. Property A consists of 59 apartment and Property B consists of 36 apartments. The real estate company thinks that the properties consume a lot of purchased energy compared to other properties that they manage in the same area. Property A purchased energy in the form of district heating and electricity corresponding to an average of 623 MWh per year during the years 2018, 2019 and 2020. The same figure for Property B was 477 MWh per year. Both properties received the grade E in the latest energy declaration (Swedish standard). The rating scale is graded from A to G, where A is the best, C is the requirement for new construction and G is the worst. The project begins with the head of administration describing the buildings, providing information and some floor plans. They contributed with, among other things, data on purchased district heating, electricity, and cold water from the years they were owners. This together provided a basis for field studies of the properties. During the site study, temperature measurements were made, products were documented, and the drawings were supplemented. Thereafter, calculations were made in Excel and simulations of the buildings in IDA ICE. Finally, a life cycle cost analysis was made The conclusion that both properties have the lighting in stairwells and elevators running around the clock, all year round. This could reduce the cost from 9,400 SEK per year to 1,200 SEK per year with sensory control. By lowering the temperature in the auxiliary spaces to 18 °C on Property A, a saving of at least 7,800 SEK per year could be made. The same measure in Property B would result in savings of 2,936 SEK per year. Property B has 36 towel warmers in the rental apartments and 9 towel warmers in different rooms in the property. All 45 towel warmers run on the hot water circulation. The 9 towel warmers in the property were not in use and should be taken out of service. This has the potential to make a saving of a total of 8,900 SEK per year. Replacing the remaining 36 with electric towel rails would provide a saving of SEK 35,000 SEK per year for the property owner. The above measures would make all the buildings to go from classification E to D according to BBR's BFE 2020: 4.