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demands, according the performance of BIPV technology. An estimation is made of the electrical
production and, also, the possibility of heat recovery through the air used for cell cooling.
The analysis of electric production of BIPV technology with best orientation for solar PV capture
(due north), during characteristic seasonal days, shows a supply between 43.6% of demand on average
winter day, and 462.5% for an average summer day. Compared to the annual demand, estimated at
8,154.5 kWh / year, the overall production reaches 14,148.9 kWh, then a relationship of 173.5% in
electricity annual generation is observed. The surpluses for the urban grid could reaches 5,994.4 kWh
per year. Considering the average consumption of an electric car of 6 km/KWh [28], the surpluses
would potentially power 36,000 km of transportation. Converting the surpluses to Gigajoules in 60
years for reaching the Powerhouse standard, the dwelling must not content over 1300 Gj of embodied
energy in the construction, maintenance and deconstruction processes; the daily consumption has
already been taken account.
The back roof and facade suited for solar capture in the higher deviation to north (94º), increases
the demand to 8,893.8 kWh/year, while the PV generation is reduced to 12,109.8 kWh/year. Despite the
inadequate orientation, it is still a Plus‐Energy house, although it implies a reduction of surpluses to
3,216 kWh/year. This surplus is useful for feeding an electric vehicle to travel a little more than 19,000
km. Regarding the balance of production and demand in different orientations, if the house has its
capturing façade towards the east, the low‐incidence solar incidence in the mornings of cold months
contributes to reducing the energy demand for heating.
3.2. Potential of BIPV and BIPVTa technologies jointly
The combination of BIPV technology with hybrid BIPVTa system allows heat recovery in air for
thermal and electrical supply. It is planned to install the hybrid collectors only in the upper roof façade,
since the demand is widely covered with the energy captured in this part; on the other hand, ventilation
of PV cells should be implemented in roof to cool the panel [29]. The thermal production is not
considered during the average day of sunny months because there are normally no demands for
heating in this season, although there is a possibility of contribution for domestic hot water.
3.3. Potential of BIPV and BISTw technologies jointly
The integration BIPV and BISTw collectors are consider jointly, with the thermal efficiency of
BISTw technology taken from Wunder CLS 1808 Solimpeks@ as described previously. The number of
collectors is established avoiding thermal surpluses, whose limitation is the maximum supply in
summer days for DHW. Due to the low slope of the roof, the aforementioned condition is achieved
with two BISTw and, consequently, there is surface for 52 BIPV panels. On annual performance,
considering a total simulated demand of 8,154.5 kWh and a thermal and electrical production of 15,361
kWh, a production‐demand ratio of 188.4% is observed. The electrical surpluses would allow the
circulation of an average electric vehicle for a 43,000 km route during a year. To reach the Powerhouse
standard, this house must not content over 1,556.4 Gj in the construction and demolition.
Figure 2. BIPVa + BISTw+BIPV technologies in the house studied (own elaboration)
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ZEMCH 2019 International Conference l Seoul, Korea