Techniques to improve the performance of hydronic radiant heating and cooling panels by geometry modification, personalisation and increasing air convection

Hydronic radiant heating and cooling panels are favoured due to their modularity, design variability, and ease of installation even in renovations. However, some of their design aspects still lack systematic reviews. This review focusses on the possibilities to improve the performance of hydronic radiant panels by geometry modifications, personalisation, and increasing air convection on the panel surface. It aims to provide new points of view and to organise existing knowledge where systematic reviews are lacking. First, typical geometries of radiant panels were established and an overview of improvement techniques was provided. Subsequently, in the main part of this review, the selected improvement techniques were classified into three main groups: (1) improving the geometry of the panels for general room conditioning, (2) adapting the geometry of the panels to create personalised environments, and (3) increasing air convection on the panel surface. These groups were further divided into a total of 16 subcategories according to the underlying improvement mechanism. The most frequently researched improvement techniques were modification of the shape of the emitting surface, efficient pipe design and arrangement, adding a condensation drainage system, adapting the panel for location close to the occupant to create a personalised environment, and inducing forced air convection on the thermally active panel surface. Several good practices for the design of radiant panel systems and a discussion of benefits and limitations of the reviewed systems have been provided.