HOK Net-Zero Energy Design Competition: Feedback Hydronics
Five designers from HOK’s St. Louis office – Brian Ballok, Lauren Field, Christoph Ibele, Brad Liebman and Leslie Wheeler – competed in the firm-wide Net Zero Design Competition as the team “Feedback Hydronics.”
The net-zero competition challenged HOK’s teams to create a conceptual net-zero energy design for a building on a site in their local communities. Teams were required to use HOK’s Sustainable Analysis Tool to obtain climate data, set energy use intensity (EUI) targets and estimate the size of on-site renewable energy systems required to reach net-zero energy.
The Feedback Hydronics team chose to design a culinary school on a site south of downtown St. Louis in the LaSalle Park neighborhood. The team’s design won third place in the internal HOK competition.
We chose a culinary school with 10 teaching kitchens and a public restaurant. From a sustainability perspective, the high-energy demand and high volume of waste associated with cooking offered interesting challenges and opportunities. Additionally, we believed the program could bring some energy to a neighborhood that is near two metropolitan areas, but fairly underdeveloped.
The building’s roof and skin system is oriented to the southeast for maximum solar thermal gain. This correlates with the site’s layout, as the building is taller on the north side and takes advantage of city views.
The roof system extends past the boundary of the site, over an adjacent parking lot, to capture rainwater and solar energy. Adding covered parking, a valuable amenity, justified designing beyond the site’s boundaries.
How did you design the building to be more efficient?
The central piece of our strategy is the structural roof and skin system. It is a quilt-like surface made up of four pod types for solar thermal collection, rainwater collection and distribution, photovoltaics and glazing to help regulate natural light.
Solar thermal and rainwater harvesting made sense as renewable energy choices based on St. Louis’ climate. The two energy types are compatible with a larger strategy of creating a loop of building systems, including radiant in-floor heating and an anaerobic digester.
How did your HOK Sustainable Analysis report impact the design?
The report helped quantify what we were up against in terms of energy demand. Once the demand was broken down, we could focus on strategies to bring balance.
What was a main takeaway from the design process?
Local conditions play a big role in setting the parameters for the design process. For example, we determined that the climate in St. Louis eliminated strategies like stack ventilation that can be very productive in other parts of the world.
View all of the project images on Flickr.