Space Heating of nZEB

Abstract

Buildings in northern and continental European climates need to be heated more than the half of the year to maintain required indoor thermal comfort; even in the Mediterranean countries space heating is needed at least occasionally. The energy used for the space heating of residential buildings has the largest share in energy demand for operation of building; consequently, the determination of the building energy efficiency class, most noticeable indicator on Energy Labelling Certificate (see Chap. 12), is based on the energy needs for space heating. Even in non-residential buildings, energy demand for heating has significant impact on the overall energy efficiency indicators and on the share of renewable energy sources used for operation of buildings. It is also important to be aware that the operation of the heating system must not compromise the other aspects of indoor living quality, such as indoor air quality (IAQ) or excessive noise. A space heating system can be decentral, local or central. Decentral heating systems consist of a stove or heater as heat generator, which is located in a heated room and provided heating only for that room. Heat generated in a heat generator is transferred into the room by radiation and convection to indoor air and structures. Central heating systems are more commonly used in mild and cold climates as they provide better indoor thermal comfort conditions and have higher overall energy efficiency of the heating. In this case, heat transfer fluid, a distribution system, and end heat exchangers in heated space are needed in addition to the heat generator. In Chap. 6, local and central heat generators are presented. The current chapter presents the design of components and the assessment of the energy efficiency of central space heating systems.