Energy use in hotels and low-energy schools: Measurements and analysis of energy use and user-related parameters
Forskningsoutput: Avhandling › Doktorsavhandling (sammanläggning)
Decreasing CO2 emissions in the building sector by improving energy efficiency isan essential part of the goal to reduce global CO2 emissions, as the sector accountedfor nearly 40 percent of the energy-related CO2 emissions in 2017.There are six main parameters that affect a building's energy use. These areoutdoor climate, building envelope properties, building services and energysystems, operation and maintenance, user-related activities and indoor climate. Thefirst three parameters can be classified as technical parameters and these have beenvery well studied in the past. To further improve a building's energy efficiency, morestudies should be carried out with regard to the last three parameters, which havenot been studied as extensively as the technical parameters. These parameters canbe classified as user-related parameters.The overall aim of this thesis is to contribute to achieving global climate goalsby improving the energy efficiency of buildings. This has been done by studyingboth calculated and measured energy use in order to understand which of theparameters have major impacts on energy use and should therefore be taken intoconsideration.This thesis studies calculated and measured energy use in two types of buildings.It focuses mainly on how user-related parameters affected energy use in five hotels,located in Stockholm and all belonging to the same hotel chain, and seven newlybuilt low-energy schools located in the southern part of Sweden. Data from thehotels was collected over several years and included measurements of energy useand the influence of two user-related parameters. In the schools, data frommeasurements regarding energy use, indoor air temperature, indoor CO2concentration, and several user-related parameters were collected over a one-yearperiod. Descriptive statistics and simulations of the buildings' energy uses were usedto analyse the collected data.The hotels in the study showed large differences in total energy use. It was alsoshown that results from one hotel, with respect to the studied parameters thataffected measured energy use, could not be applied to the other, similar, hotels. Oneway of attaining more detailed information and identifying the energy deviationswould be to study a hotel’s sub-systems (for space heating/cooling, pool, etc)individually. This would help engineers in their design work and allow more8accurate calculations of potential energy savings of any capital investments in thespace heating systems, or any other systems.Comparisons between measured and estimated energy use showed that there werelarge discrepancies in the studied schools. These varied from -44 to +28 percent.The study showed that the user-related parameters had a more dominant influenceon the variations of building energy use than the technical parameters. Of the studiedparameters, indoor air temperatures, ventilation rates and ventilation operating timeswere shown to be the user-related parameters having the greatest influence onbuilding energy use. The use of electricity for lighting and electrical appliances hadsomewhat less influence on the total energy use while occupancy rates and energyuse for domestic hot water supplies had little influence in the studied schools.Although only seven low-energy schools were included in the study, it could be seenthat the measured user-related parameters could vary considerably. This means thatnot only more measurements in more schools are needed in the future but also thatby only presenting an average value per parameter energy engineers could be misledwhen calculating energy use. For thisreason, this study also presents standarddeviations of the studied parameters.
|Enheter & grupper|
Ämnesklassifikation (UKÄ) – OBLIGATORISK
|Tilldelningsdatum||2020 okt 16|
|Status||Published - 2020 sep 14|
Ingen tillgänglig data
Indoor air temperatures, CO2 concentrations and ventilation rates: Long-term measurements in newly built low-energy schools in SwedenBranko Simanic, Birgitta Nordquist, Hans Bagge & Dennis Johansson, 2019, I : Journal of Building Engineering. 25, 100827.
Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift