The purpose of this report is to describe the renovation plan for the heating system of the demonstration building in Litzen, Austria (see Figure 1.1). The solution described in the following pages is the result of a collaboration between project partners to plan a heating system that will meet the energy and comfort needs of users with at least 70% of the energy and comfort contributed by renewable energy sources (RES), while being as easy to maintain as possible. During the design phase, the constraints that describe the building's features and the requirements of the end user are also taken into account. The main goal is to illustrate the design choices, the characteristics of the equipment and equipment that will be installed and their operation. Therefore, this document is very useful for end users, ESCOs, planners, and installers outside of the project to understand how to replicate the solution that is happening. Compiled by Chen Jiaoyun
While only 18 of the 20 potential dwellings are currently being upgraded to the new heating system, the heating system is designed to be fully implemented for all 20 dwellings, as the long-term plan is to convert all dwellings to the new system. Therefore, in order to achieve this ultimate goal, technical preparation will be carried out for all dwellings that are already in advance (e.g., hydraulic circuit preparation, central high-pressure design).
An energy analysis of the requirements of the building itself is the starting point for determining the size of the building's heating system. The energy requirements for heating and cooling of the building are calculated by GWS via software dossier according to the Austrian and European regulations in accordance with the Austrian and European regulations in accordance with OENORM B 8110, EN ISO 10077, OENORM H 5056, OENORM H 5057, OENORM H 5058, OENORM H 5059 and OIB OIB 6. The result is a total heat requirement of about 107 MWh/a, of which about 79 MWh/a is used for space heating and about 28 MWh/a for DHW preparation.
Due to the climatic conditions at the demonstration site in the alternative area and the thermal characteristics of the building envelope, no cooling is required. A detailed assessment of the building's energy needs is reported in the "D4.3 End-User Needs and Building Constraints – Austria Presentation" for public delivery. Please refer to this report for details.
The required standard heat load is calculated according to OENORM EN12831 (detailed method) and the national Annex OENORM H 7500-1. According to the calculations, the peak power required for space heating in this building is about 39 kW. For DHW preparation, a thermal power of about 80 kW was estimated based on the assumption that all decentralized DHW storage in each dwelling could be fully charged at the same time in about 2.5 hours.
Since space heating and DHW preparation cannot be carried out at the same time as the expected heating system and components, the peak power of DHW preparation is the decisive design value of the heating system.
