The Influence of Energy Renovation on the Change of Indoor Temperature and Energy Use
TalTech, Estonia, 2018
Doctoral thesis proposes solutions of rainwater usage for domestic hot water production in buildings
TalTech, Estonia, 12.06.18
The PhD thesis proposed a solution for using stormwater thermal energy. The comparison of three types of buildings – a shopping centre, an office building and an apartment building – indicated that an underground stormwater storage tank is an optimal solution for a shopping centre, since it has the best conditions for the rainwater harvesting and hot-water consumption. Thus, the PhD thesis provides a novel solution for utilization of stormwater as a low-temperature water thermal energy source for buildings, as well as for cooling of buildings, if necessary.
Engineers: In nearly zero energy buildings in Estonia, special attention must be paid to window design
TalTech, Estonia, 29.05.18
The studies of the insolation, i.e. direct solar access to premises, indicate that the current requirements set for the minimum insolation hours (at least 2.5 hours of uninterrupted sunshine to the premises) are not justified in designing modern nZEBs. The research demonstrated that following these requirements increases the risk of overheating. The requirements should be based on daylight factor values (insolation characterises direct solar radiation, whereas a daylight factor characterises diffuse radiation, i.e. cloudy weather).
Retrofit cost-effectiveness: Estonian apartment buildings
TalTech, Estonia, 2016
The economic viability and investment cost of the energy retrofit of apartment buildings are analysed through different energy efficiency levels. To analyse retrofit policy cost-optimal energy efficiency levels and investment costs, a baseline of measured actual energy usage of apartment buildings was created and then individual energy-saving measures and retrofit packages were composed. The cost-optimal level over a 20-year period for apartment building retrofit was a low-energy-building energy performance level, with an investment cost of €150–170/m2. Retrofit to low energy building level would be economically viable but the investment capability of apartment owner associations is found to be insufficient for the necessary investments to achieve low-energy-building energy performance. Therefore, it is necessary to determine what levels of financial support can encourage retrofit to occur. The analysis of the current retrofit shows that subsides will increase investment by apartment owner associations into energy efficiency improvements. The target group for energy efficiency retrofit subsidies should be apartment buildings that reach low energy building performance level or at least match the energy performance requirement for new buildings.