The long sides of Net Zero Co2urt face north and south, and have a 35% window-to-wall ratio that optimizes daylight without sacrificing energy performance.
Designers at HOK and daylighting and energy consultants at the Weidt Group recently came together to see if they could design a market rate, net-zero-carbon-emissions office building. Their design exercise resulted in “Net Zero Co2
urt,” a four-story, 170,000 ft2
) office building for a downtown St. Louis site, and with an estimated payback period of 12 years for features going beyond a building meeting LEED Certified standards.
The Missouri climate of fairly harsh winters and hot summers was a challenge, as are regional costs for conventional electricity—among the lowest in the country at about $0.07/KWh. According to HOK, the modeled building uses 21.9 KBtus/ft2
, producing 76% less carbon emissions than a conventional office building, and with only minor additional first costs—total construction costs as modeled would be $223/ft2
. The building’s energy needs are met with a 52,000 ft2
photovoltaic array and 15,000 ft2
of solar thermal panels.