IBPSA-USA Presence at the 2019 Lowdown Showdown

This September, the 2019 ASHRAE Building Performance Analysis Conference in Denver marked the 5th LowDown Showdown energy modeling competition. The LowDown Showdown has become an annual energy modeling competition where teams compete to showcase their design and modeling skills, developing highly sustainable and innovative projects. Historically, the competition criteria focused on reducing building energy usage, with teams shooting for net-zero energy consumption. This year set the bar higher, expanding the scope to include elements beyond just energy. Teams were challenged to design a 90,000-square foot City Hall building in San Diego, which would be a Net Zero facility during regular operations, with the ability to act as an Emergency Operations Center if disconnected from utilities for up to two weeks. Additionally, the building needed to be Resilient towards an emergency event, Sustainable, and enhance the Health and Wellness of the occupants. Five teams took the challenge at the competition and presented at the conference. We are happy to announce that out of the five teams, two originated from the recently formed IBPSA-USA Phoenix Chapter

The IBPSA-USA Phoenix Chapter started in November 2018 with five members passionate about building simulations, with the intent of learning from each other; educating clients, the community, and emerging professionals about the importance of building simulation and analysis, and growing the IBPSA-USA chapter in the Southwest.


Team C.R.E.A.M. (Carbon Rules Everything Around Me) included members of WSP’s Built Ecology and Building Enclosures groups from six offices across four times zones. The team used the competition as a chance to collaborate with fellow members on a multi-faceted design project that allowed everyone the chance to step-up and showcase their expertise. The initial challenges of organizing a breadth of skills across multiple offices sparked an immediate need to rethink the “critical path” approach; with the team opting instead to develop the project along parallel work paths. To accommodate this approach, the team utilized a pallet of Grasshopper tools developed using plug-ins such as DIVA, Honeybee, and Ironbug to perform most of the design and performance modeling, in lieu of creating a large centralized model. This allowed the team to integrate design exploration and multiple types of analysis within the same digital environment.

The primary goals for the team’s design were not to just address resiliency, occupant wellness, and energy, but to also address design from the perspective of the global warming impact from carbon and refrigerants. One of the first areas they took into consideration was optimizing the building massing to minimize energy consumption from HVAC and lighting and the embodied carbon from the building material usage, specifically from steel and concrete. While members of the structural team looked for ways to incorporate mass timber in a seismic region, they were also providing input on parametric studies being performed to optimize massing for envelope gain, daylighting, and natural ventilation. This resulted in a porous, self-shading structure oriented around a central courtyard that reduced steel usage by incorporating mass timber structural elements. 

The competition provided an opportunity to test the effectiveness of tools and workflows, as well as a venue to explore concepts and discover new ways of analyzing building performance. As an example, the team studied the project’s chiller plant which consisted of modular, heat recovery chillers with low GWP refrigerant blends and found them to have reduced energy efficiency, but tremendous improvement to emissions. Ultimately, the greatest value wasn’t from individual analysis, but from developing the methods to coordinate and integrate peoples’ individual skills into a cohesive unified effort.


Team Operation RESHED was formed across multiple regions within DLR Group offices. For the team it was all about integrating the simulations and data into the design practice. Though the team used a more traditional approach while selecting the tools for the analysis, the focus was more on collaborating among different disciplines in the team and using the data from the simulations to drive the decision-making process during each and every phase of design, whether it be site selection to prepare for resiliency from site level or finding the biggest energy user in the building (Datacenter) or taking a deep dive into the mechanical design to add active chilled beams with desiccant dehumidification for effective energy use. The team had fun during the whole process, collaborating across multiple regions and multiple disciplines, learning from each other. The team had monthly design shares within multiple regions at DLR Group to brainstorm innovative architectural and engineering ideas for the project’s success and learn from the expertise of professionals within the firm. These ideas were then refined by the team using the power of simulations and data analysis.  

In the end, the design was massed vertically to transform the skyline of San Diego with thin north-south orientated floor plate allowing natural daylighting and allowing natural breezes to flow through. Reusing the shipping containers on the building facade helped in reducing the carbon footprint, along with shading the exterior glazing, and creating outdoor food gardens on each level to improve the occupant comfort. Other energy saving strategies included LPD reduction, DOAS with active chilled beams, heat pump heat recovery chiller, plug load reduction and power production using photovoltaic panels and wind turbine leaves. The design concluded with 60,000 KWH hydro-pneumatic energy storage system and 30,000 gallons of potable water storage which would be used during an emergency event. 

Overall, the IBPSA competition helped the teams to combine different architectural and engineering facets to drive towards a holistic and futuristic solution. The competition gives the participating members a better understanding of the current issues in the building industry and gives a chance to connect, collaborate and learn from different individuals. The IBPSA competition and chapters is not just about energy modeling and data analysis professionals. IBPSA is a platform to connect people from diverse backgrounds to work and collaborate with each other towards a common goal.