ZEMCH 2015 - International Conference Proceedings | Page 305

Energy analysis
Energy analysis programs Ecotect, Hot2000 and RetScreen were used by the students for the calculation of the indicators mentioned in the Methods. Due to the short period for their learning
and complexity of input data (even in simpler programs, like those), some problems were raised.
The calculation of building energy consumption and its systems is not an easy task (the achievement of zero or net zero energy buildings is even more challenging). The students faced difficulties and did not understand the connection between them in the design process completely.
They could not compare distinct design alternatives. The main energy program (HOT 2000) was
developed for Canada, where energy demands and design strategies for zero energy buildings
are completely different from those in Brazil. In Brazilian climates, the main issue is the avoidance
of heat loss during winter through the use of a highly insulated and air tightened envelope. In
São Carlos, (and most Brazilian cities), operable windows and natural ventilation, at least during
summer, are important strategies for the achievement of thermal comfort. Most houses (social
housing or not) do not use air conditioning and the electric shower is the main contributor to
the energy consumption. Chvatal; Corvacho, 2009; and Chvatal, 2014 discussed whether a highly
insulated envelope would impact on the thermal performance in less cold climates, with warm
summers. Moreover, evaluating the impact of natural ventilation on the building thermal consumption is much more complex than using the steady-state programs mentioned and unviable
during a workshop. Figure 12 shows the thermal comfort analysis of Group C. This group included
students that addressed building energy efficiency as their research topic, therefore, their thermal comfort analysis was conducted in a more detailed way.

Figure 12 – Group C - thermal comfort analysis

Exploration of the ZEMCH workshop USP 2015

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