Heat Supply Systems of Renovated Residential Buildings

Since 2010 in Latvia energy efficiency improvement measures in residential buildings have been actively implemented with an aim to reduce heat energy consumption and heating costs in houses. The aim of the study is to find optimal solutions for reducing energy consumption and increasing energy efficiency indicators of heating and domestic hot water systems. In the framework of the study heat consumption analysis of the domestic hot water supply systems in residential buildings was carried out. The results showed that heat energy savings and home energy efficiency theoretically and optimistically predicted by the renovation project after three years of operation of renovated houses were not reached. It was concluded after a thorough analysis that the external enclosing construction insulation reached predicted energy savings. Energy efficiency of the heat supply system was low, thermal energy consumption was higher than expected. Central heating systems are hydraulically unstable because heat in apartments is regulated emotionally, exceeding the regulated operating mode. The domestic hot water supply systems low energy efficiency causes relatively large thermal energy losses in hot water distribution and in circulation pipelines. The project was implemented in 2014; after three heating seasons of operation data monitoring, fixation of project deficiency and correction of solutions were carried out. According to the operation data monitoring, this innovative system is the most functional and energy efficient, corresponding to installed requirements of the project. After the assembly was completed the system was tuned to work in calculation mode and put into operation. During operation while heat consumption regime is changing, the functional efficiency does not change. Apartment heating system heat output is automatically regulated according to the room temperature. Preparation of hot water is provided in every apartment's boiler capacity (in local space heaters) with the combined heating system heat transmission at 70 degrees C temperature. It provides hot water heating to 60 degrees C close to the final user and prevents the growth of microorganisms in hot water distribution system pipelines of the end user.