Conclusion, Research Needs, and Future Directions - Modeling, Design, and Optimization of Net-Zero Energy Buildings - page 492

realistic operation so as to have a largely predictable and manageable
impact on the grid. Smart buildings optimally linked with smart grids
will enable a reduction in the need to build new power plants; and,
3. The concept of solar optimization requires optimal design of building
form and orientation so as to enable the maximum capture of solar
energy from near-equatorial facing facades and roofs for conversion to
solar electricity, useful heat, and daylight.
This topic has revealed the importance of choosing the right approach and
model resolution at different stages of the design. It also identified
important gaps in building simulation and design tools as well as
methodologies. Some key gaps in building simulation software and design
methodologies are listed here:
1. Modeling of building-integrated solar technologies at different stages of
the design. For example building-integrated photovoltaic/thermal
(BIPV/T) systems and semitransparent PV windows are
energy-generating elements that also have a thermal function and
possibly a daylighting function. Their proper design requires
simultaneous consideration of impact on cooling loads, heating loads,
comfort and envelope performance, and durability.
2. Systematic analysis of design options is needed in the early stages of the
design when the geometry of the building is not fully fixed. Choice of
thermal mass strategies has an important impact on structural design
and, accordingly, they need to be assessed in early-stage design tools.
3. Integrated thermal, daylighting, and natural/hybrid ventilation
simulation and design of buildings.
4. More accurate prediction of comfort - thermal, visual, and acoustic - at
different stages of the design in an integrated manner with energy
simulations. Comfort can be much subtler and complex than merely
using indoor air temperature as a metric. Certain common Net ZEB
strategies (e.g., open spaces and hard surfaces) can compromise
comfort if care is not taken during design. Therefore, detailed models
with a comprehensive reporting of occupant comfort conditions (e.g.,
based on ASHRAE Standard 55) is essential.
5. Integrated study of smart building operating strategies with energy
design and comfort studies. As building design and operating strategies
become more advanced, demonstration projects and case studies are