## 1 Introduction  
The 1980s saw the development of systems of conditioning of architectural spaces based on capillary mats of polypropylene tubes of about 3 mm in diameter, separated by approximately 10 mm. Cold or hot water circulates through these mats. They can be applied to any interior walls--floors, walls and ceilings--using a range of techniques--such as plasterboard, false ceilings, false walls or plaster projection, achieving healthy, silent and comfortable air conditioning. In addition, these radiant surface conditioning systems lead to notable energy savings compared to conventional air conditioning systems [1].  
Radiant Surface Conditioning systems using PPR capillary mats work mainly by radiation, and secondarily by convection. When working by cooling or moderately heating some walls, with minimal dehumidification in summer, and without using cold or hot air impulsion, significant advantages are achieved with respect to convective systems. The sound level decreases dramatically, the air moves at very low convection speeds, which provides comfort, and summer air temperature is approximately 2 \({}^{\circ}\)C higher than in the case of convective systems. In this way, the comfort level increases significantly. In addition, notable energy savings are made, as certified by reputable research institutes. The main factors are the water's greater capacity to transport energy compared to that of air, the system's self-regulation, and the reduction of thermal loads as indoor air temperature is higher in summer [2].  
Possible schematic diagrams of these capillary mat systems have been widely addressed in recent publications [3] (Figure 1). When working with water at moderate temperatures in both summer and winter, it is feasible to use alternative energies: solar panels, lithium chloride-based chemical energy accumulation systems [4; 5], absorption systems, geothermal energy systems [6] or use of seawater [7], among others [8].  
In recent years, ceramic materials have undergone huge technical improvements regarding mechanical resistance and behaviour towards external agents of humidity, temperature or UV radiation, presenting almost non-existent water absorption. To the inalterable nature of porcelain stoneware, we must add, as we will see later, the production of panels in large formats and thicknesses, enabling to use the material on ventilated facades, or interior linings in functional spaces other than bathrooms and kitchens.  
In the present work, we studied the application of large-format thermal ceramic panels (TCP) to the floor of the Museum of the University of Alicante (MUA, by its Spanish acronym), with the aim of implementing radiant floor air conditioning. Previous studies presented the results obtained from applying TCP panels on walls and ceilings [9], instead of using plaster or steel sheets, but they did not apply them to floors. Novel 20 mm-thick large-format ceramic pieces allow us to apply the panels to flooring combined with the application of PPR capillary mats. It would be possible to condition the MUA in winter and summer, with a dehumidification system based on fan-coils, and obtain substantial energy savings. The option to incorporate a thermal solar panel system on the rooftop was also examined. In this way, in winter, a system of hot water production is applied, and water is cooled by chemical energy (solar cold), providing the system with alternative energy. As we will see, big energy savings were made, with acceptable amortisation periods regarding the installation's required investments.  
Figure 1: Schematic diagram of a capillary mat installation, with fan-coils for dehumidification, and control substations.