Conclusion, Research Needs, and Future Directions - Modeling, Design, and Optimization of Net-Zero Energy Buildings - page 494

For Net ZEBs to become widespread the next step is to consider optimal
design configurations for clusters of buildings and neighborhoods while
considering interaction with electricity grids/microgrids. While net-zero
energy buildings place considerable emphasis on individual buildings, we
cannot lose sight of the bigger picture. Grid-tied Net ZEBs still have
considerable upstream impacts on the environment and energy-supply
infrastructure because of their diurnal and/or seasonal dependence on a
centralizedenergysupply.Futureresearchanddevelopmentmustrecognize
the complex interactions between individual buildings, the community, and
the larger scale (e.g., urban and grid-wide).
Through integration, the net-zero energy goal can be achieved at the
community level, while allowing significant design flexibility at the
individual building level. Different pathways for achieving net-zero energy
balance at the community level need to be studied, including solar
optimization of building form, density, mix of solar and energy efficiency
technologies (e.g., BIPV/T and heat pumps, thermal storage, possibly some
district heating). One possible scenario suggests that buildings can be
integrated into traditional street patterns while ensuring that one or more
large planar surfaces are optimally oriented to capture solar energy. There
is also the possibility of integration with seasonal heat storage and district
heating systems for cold climates. The optimal mix of technologies, their
integrated design, and operation will depend on climatic conditions and the
local conditions, including cost and incentives. Plug-in hybrid and electric
vehicles can be integrated into the community energy concept, serving as
electrical storage and load management devices, but also providing backup
power to the houses during emergency situations such as earthquakes.
In closing, this topic has demonstrated that Net ZEBs are a viable design
objective for most climates through four detailed, high-quality case studies.
Modeling and design issues for the most common and appropriate
technologies, systems, and strategies for Net ZEBs were outlined. It is clear
from this research and demonstration projects that attention to detail from
early-stage design to operation and use of appropriate modeling and
simulation tools is essential.