Experimental testing of cooling internal loads with a radiant wall

Abstract

Thermally activated building systems (TABS) consist of pipes or ducts embedded in the building structure. This is a well-known technology for its capability to reduce energy use for cooling buildings. Additionally, TABS help integrating renewable energies, such as free-cooling with ground heat exchangers (GHE). However, TABS cooling load is sensitive to the internal load, and the use of GHE for free-cooling is limited to low energy buildings. In a previously published research, a radiant wall cubicle without internal gains demonstrated to achieve significant energy savings. However, the current research showed that under domestic and office scheduled internal gains equivalent to 42 W·m-2 the radiant cubicle increased its energy consumption for cooling more than the reference cubicle with air-to-air heat pumps. As a result, the radiant cubicle used around 20% more energy than the reference at air temperature set-point 24 ºC but saved around 20% compared to the reference at 26 ºC. Despite this, the radiant wall could still reduce the cooling cost through peak load shifting even though it showed to consume more energy than a conventional HP.

The work was partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER), ENE2015-64117-C5-3-R (MINECO/FEDER), and ULLE10-4E-1305). GREA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. The authors would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123) and the city hall of Puigverd de Lleida. This projects has received funding from the European Commission Seventh Framework Programme (FP/2007–2013) under Grant agreement Nº PIRSES-GA-2013-610692 (INNOSTORAGE) and from European Union's Horizon 2020 research and innovation programme under grant agreement Nº 657466 (INPATH-TES). Alvaro de Gracia would like to thank Ministerio de Economia y Competitividad de España for Grant Juan de la Cierva, FJCI-2014-19940.