Utvärdering och åtgärdsförslag av energianvändning i kontorsbyggnad
AbstractEmbla 5 is an office building which has done a large improvement. The clients of this building has made an order of WSP and the student Anders Kempe to calculate the use of energy for the building, and after that result proposing further measures which can decrease the energy use of Embla 5.The ground for this report is when calculation of the present energy use of the building is stated. To make that information of a number of parameters such as envelope, the heating system and ventilation has been located and set in to the simulation program IDA ICE which calculate the energy use.To improve the energy use further this project has been concentrated to change the system of ventilation. Today the ventilation system is of the kind CAV (constant air volume) and the air flow is dimensioned for after recommendations from BBR and Arbetsmiljöverket in the office spaces. Consider that Embla 5 is an office building where the people only staying for 8-10 hours/day so was the ide to see how much energy saving if the air flow is reduced the time people not being in the building. This VAV-system (variable air volume) was set to go with full air flow weekdays 06:00-19:00 when people can be in the local. All the time around that the air flow is been reduced to 20 % of dimensioned flow (solution 1) and 40 % of dimensioned flow (solution 2) with the same kind of time control. By these solutions the rate of energy use is been calculated and been compared to the present energy use. The saving of energy for the two solutions been around the same about 100 000 [kWh/year]. With a energy price of 1 [SEK/kWh] the saving in money being 100 000 [SEK/year].Before Embla 5 renovated the heating rate were 400 000 kWh/year and after renovation the heating rate were 300 000 kW/year. The heating rate had reduced thus the building had been four times bigger. The reason of that is the older part of the building had very large transmissions losses and newer part of the building was built with material with low u-value which decreases the transmissions losses. Another reason is that a new FTX-system is placed in the building with a better efficiency than the older FTX-system.