The development of novel systems for the on-site integration of renewable energy in buildings is increasingly demanded for the reduction of the energy consumption resulting from domestic hot water, heating and cooling usages. Within this context, the development of efficient solar collectors for domestic hot water demand production that benefit from their architectural integration in buildings is of high relevance.
In the present study a novel solar collector device with a tube-in-tube concept that integrates domestic hot water storage and absorber in a single unit, is tested under the standard ISO 9459-5. The thermal performance of the collector is evaluated by means of the so-called DST (Dynamic System Testing) method that allows prediction of its annual energy efficiency under different climate condition scenarios. The study concluded that three collector modules in series can provide a high annual DHW energy coverage between 62-70 % for Southern European climates and in the range of 30-40% for Central and Northern European climates. Along with its compactness and efficient design that allow easier architectural integration on roof ridges, an additional advantage of the system is that its cylindrical geometry makes it possible to rely on a significant surface for full diurnal radiation absorption, independently of solar orientation. With the objective for this new development to be technically and economically competitive compared to available solar domestic how water systems (SDHW), it is currently under the pre-production phase and ready to enter the market in 2018.