Net ZEB Design Processes and Tools - Modeling, Design, and Optimization of Net-Zero Energy Buildings - page 229

3. What is the appropriate balance between energy conservation measures
and renewable energy generating capacity?
Fig. 4.28 Example Sankey diagram for a passive solar house during a
winter week
4.3.5 Future Needs and Conclusion
This section examined different Net ZEB building design and simulation
methodologies and demonstrated the importance of choosing the
appropriate model resolution at different design stages. There is generally
a trade-off between accuracy and modeling effort. The time required to
create high-resolution models normally prevents them from being useful
at the beginning of the design process - when designers require rapid
performance feedback. Therefore, the use of one or more simple tools is
encouraged as long as the limitations are understood. Escalation to more
detailed models can be achieved in numerous ways, as previously described.
The qualities needed from Net ZEB tools differ from tools required for
conventional buildings in two major ways:
1. Need for tools with higher levels of accuracy and certainty. The Net
ZEB definition demands an absolute level of certainty in energy