Energetic study of a residential building in Skutskär and savings proposal

Abstract: This project consists on the Energy audit carried out on a residential building in Skutskär, property of the company Älvkarlebyhus, which is placed in the Älvkarleby municipality, belonging to Uppsala County in Sweden. The aim of the Energy audit is to obtain how much Energy is used, when is it used and how is it used. As well as the costs of the Energy use. The aim of the Energy audit also consists in reduces the Energy use applying efficiency measures. The audit carried out consist on identifying the heat losses and heat gains of the building, thus establishing an Energy balance that will reflect the Energy state of the building and finally propose some efficiency measures that could be applied. With this purpose, a strong method was developed in order to obtain as accurate results as possible. This method studies separately each component of the balance in order to get a better approach. The idea when working and present the results is to manage all the information in an easy way and present it in an easily understandable way for everyone, thus was used a spreadsheet. The expected results have been achieved; the difference between the heat losses and gains is of 0 MWh, which represents the balance 0 and all the values obtained are according to the experience values, which achieve the expected results. The total heat gain of the balance accounts for 1575,23 MWh. It is compounded by the District heating consumption which accounts 742,22 MWh that represents the 47 % of the heat gain and by the free heating which accounts for 832,79 MWh that represents the 53 %. The free heating is compounded by solar radiation which accounts for 643,36 MWh representing 41 % and for Internal heating which accounts for 189,43 MWh that represents 12 %. The total heat loss of the balance accounts for 1575,23 MWh. It is compounded by transmission losses which accounts for 875,46 MWh that represents 56 %, mechanical ventilation which accounts for 369,89 MWh that represents the 23 %, natural ventilation which account for 182,88 MWh that represents 12 % and hot tap water which account for 147 and represents 9 %. The efficiency measures will improve the Energy use in the buildings; especially in the cases were the Energy usage is too high, as in the case of transmission losses. Thus, the efficiency measures will be proposed mainly to alleviate the high values but also to improve other inefficient uses of the Energy. There are some efficiency measures proposed for every component of the balance and there is also some recommendation for the company in order to implement the most attractive ones, taking into account its profitability. These measures are only proposed and not studied deeply because of the main limitation of this thesis. Therefore, it is recommended to continue the study in order to examine and analyse deeply each measure, according to the energetic survey already done.