Recent Trends and Developments Regarding Summer Comfort and Low Energy Cooling in Italy

One of the fastest growing sources of new energy demand is space cooling. The studies EECCAC and EERAC predict a four-fold growth in air- conditioned space between 1990 and 2020 (Adnot, J. et Al, 2003). The IEA Future Building Forum identified space cooling as one of the fastest growing sources of new energy demand (International Energy Agency, 2004). In its preamble, the European Energy Performance of Buildings Directive (EPBD) states that “Priority should be given to strategies which enhance the thermal performance of buildings during the summer period. To this end there should be further development of passive cooling techniques, primarily those that improve indoor climatic conditions and the microclimate around buildings” (European Communities, 2003, p. L1/66). But such passive cooling technologies, which are already available and cost effective (such as use of well designed sun shades, efficient lighting and office equipment, passive cooling via thermal exchange with the ground, night ventilation etc.) are not widely used in an integrated way today: the most common choice for a building owner when addressing summer comfort issues is still mechanical cooling, often without previously investigating other available measures regarding the optimization of envelope features (e.g. solar protections, glazing solar factor, thermal insulation of opaque surfaces, thermal mass). This paper is based on some preliminary results of the project KeepCool2 (KC 2 in the following) to contribute to a broad market transformation from “a cooling approach” to “a sustainable summer comfort approach” which makes effective use of • • • the most advanced knowledge and technologies for good design of building envelope (or redesign through retrofit actions) passive cooling techniques and comfort responses and adaption mechanisms of occupants (according to the new European Standard EN15251/ 2007, (CEN 2007a), (Nicol and Pagliano 2007)) In the Keepcool project “sustainable summer comfort” is defined as “achieving good summer comfort conditions with no or limited use of non renewable energy1 and through the use of environmentally non-harmful materials”, according to the definition set up in the KeepCool project (Varga and Pagliano 2006, see also http://www.keep-cool.net/keepcool.html).