Net ZEB Case Studies - Modeling, Design, and Optimization of Net-Zero Energy Buildings - page 451

collectors without PV integration). As the building increases in height, the
importance of façade surface area increases relative to roof surface area.
The thermal energy collected from the solar thermal energy collecting
systems can be used as heat sources for a heat pump. The heat output from
the heat pump can be used for space heating through heating a hydronic or
air-based BITES.
7.4.4.3 Active Building-Integrated Thermal Energy Storage
ActiveBITES,suchashydronicorventilatedmassiveslabs/walls,otherthan
being used solely as the media to provide space heating and cooling, can
alsobeusedtostorerenewablethermalenergyforbuildingpreconditioning.
For example, BITES can be preheated with collected heat from passive solar
heat gain and active solar thermal collectors (e.g., transpired collectors and
BIPV/T), and precooled with available outdoor cool air, through direct heat
exchange or with a heat pump.
With the desired temperature profile and thermal load of the building based
on the set temperature profile and weather forecast, frequency domain
models of BITES systems can readily provide predictive control information
for BITES systems, such as the thermal charging rates and schedule.
Frequency domain models also provide insight in optimizing the design of
active BITES systems.
7.4.5 Conclusions
The purpose of this case study was to investigate key design features of
the RSF and abstract them to an archetype building/cross-section that can
inform the design of similar buildings possibly under other climatic
conditions and modified function. A key part of the work was modeling of
thermal and daylighting performance of a typical zone with a number of
design alternatives. The solar utilization of the south façade and roof for
electricity and useful heat is also discussed.
The design and performance of the NREL RSF were discussed. An
alternative design investigation focused on daylighting and solar heat gain
control was conducted. The potential contribution from transpired solar
thermal collectors, active building-integrated thermal storage systems, and
building precooling with nighttime ventilation were evaluated. This study
also demonstrates, in the context of office buildings, how to model similar
advanced high-efficiency buildings, and how to perform model-based