ZEMCH 2015 - International Conference Proceedings | Page 601

Solar Energy Integration
The incorporation of solar energy into housing in Chile is still incipient, despite the good potential offered by solar irradiation received in the country (between 1.800 to 1.500 kwh/m2 annually
in the most populated zone). State programmes are beginning to be put in place to install solar
technology in new-build homes and foster electricity co-generation for privately-owned initiatives, usually involving adding rooftop equipment to the home or industrial installations. Urban
surveys carried out in some Chilean cities, such as Calama, Vitacura (in Santiago), Valparaíso and
Concepción, have detected significant potential contributions to domestic energy supply if integrated solar capture systems were to be installed in roofs (ARAYA et al, 2014; GARCIA et al, 2014b).
Although the energy collection and demand have seasonal and daily disparities that requires
storage or share. Some on-line maps (like msc.ubiobio.cl) are motivating solar systems installation in homes, providing specific recommendations according building features and estimated
demands (Fig.6).

Fig.6. Solar Map of Concepcion and information provided for a house.
In the city of Concepción, in a review of housing models in developments built in the central commune since 2006 (representing 90% of total housing built over this period), a clear similarity in designs was detected (ZALAMEA, GARCIA; 2014), arising from the combination of public acceptance
and local building capacities. Estimates were then calculated for installing integrated equipment
on the largest and best-orientated roof section (covering approximately one quarter of total roof
area) using a couple of thermal and a dozen photovoltaic panels (or alternatively a number of hybrid thermal-photovoltaic panels). Dynamic simulations and standard calculations revealed that
average energy collected in each house could fully cover domestic electricity needs and supply
two-thirds of hot water and one-third of heating demands (according to domestic consumption
statistics verified on-site). However, there are substantial differences in roof design since some
house models are highly fragmented (with over five roof sections per home) and roof angles vary
between 25° and 50° (apparently due to cost factors and local customs). Thus, more regular roof
designs permit better system integration and achieve up to five times more solar energy capture
potential than less regular models. The available technology offers a range of possibilities that
can be combined to best respond to the range of patterns of domestic demand (Fig.7). However,
the considerable excess thermal heat and electricity production in summer periods would ideally
need to be fed into the urban supply grid. Daily variations in production would also require considerable storage capacity, either in tanks or batteries, which would increase system costs. In contrast, estimated winter supply is insufficient to cover demand. On the other hand, any investment
takes between five and twenty years to recuperate under current legislation and financial rates, a
factor that reduces the likelihood of implementing this technology.

Eco-friendly materials for the energy retrofit of existing buildings

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