What do a handful of Microsoft Corporate offices, the Austonian in Austin, the University of Arizona's College of Architecture, Planning & Landscape Architecture building, and San Diego International Airport (SAN) have in common? Each building practices air conditioner condensate reuse for alternative irrigation methods, cooling, and water conservation efforts. 

While these are a few examples of buildings around the globe adopting this practice of water reuse, professor Jonathan Bean from the University of Arizona's College of Architecture, Planning & Landscape Architecture explains the realistic outlook on condensate reuse. "Reusing condensate is important but not a critical piece in counteracting climate change," he shared with Chris Malloy of Bloomberg CityLab. Instead, Bean believes there are more effective strategies out there like "making buildings smaller and reconsidering refrigerants." 

"While the water volume from air conditioners humming in big buildings is small compared with rivers and the underground aquifers, it can make a difference, especially when combined with other alternative water sources like rainwater capture and treated wastewater. Even this smaller volume can green gardens, fill toilets, provide cooling, meet partial needs of single buildings, shorten water supply chains (saving energy), and make people more conscious of water’s scarcity," explains Malloy.

For example, The Austonian, a 56-story residential skyscraper in Austin, captures around 12,800 gallons of condensate a year. "Commercial developments that use reclaimed water to replace between 1 million and 3 million gallons of potable water per year can obtain $250,000 in city funding; those that save more than 3 million can get $500,000. Similar programs already exist in San Francisco and San Antonio," Malloy reports. Further pushing the envelope for water condensate reuse, the San Diego International Airport teamed with Ballast Point & Water Works to produce beer through purified condensate. 

While condensate reuse systems aren't ideal in all parts of the world, the upfront capital costs buildings that have adopted this system have seen the benefits. Although additional obstacles for implementing this to all building typologies also depend on location, Bean shares with Malloy that the goal to make more "climate-intelligent buildings" makes sense. "It's a resource that you're expending a fair amount of energy to generate, so why wouldn't you?"