Paper Title
Sustainable Tall Buildings: Microalgae Facades for City’s Energy Production, Water Conservation, and Good Air Quality

Abstract
This research project addresses a looming crisis – the potential consequences of anthropogenic climate change – by investigating microalgae facades and their impact as an innovative and sustainable building technology for tall building enclosures. Microalgae facades offer a solution toward reducing this future strain on human population centers and dense urban sites by creating the built environment that offer good indoor air quality, better occupant satisfaction, and produce carbon-free energy. The research addresses the technical design of a novel microalgae facade design process that aims for net-zero architecture practice, with a holistic integrated approach toward the effective fabrication, optimal operation strategies, maintenance, retrofit, and repair of these facades. The preliminary research indicated that the microalgae facade has both long- and short-term benefits that are significant. The microalgae façade’s successful utilization of the natural biologic process of absorbing CO2 and releasing O2 provide good indoor air quality with reduced dependence on energy-intensive mechanical equipment. Additionally, the research also explored user perceptions of the use of microalgae, the results of which can be used to improve the awareness of this technology.Preliminary analysis indicated that an office building retrofitted with microalgae facades results in reduced energy consumption by 20% compared to the original building due to its improved energy and daylighting performance. The retrofitted microalgae façades also cut down on annual operational costs by $80,000 and lowers the annual CO2 emissions by 6 tons which equates to $2.4M energy cost savings and 200 tons of CO2 reduction over a 30-year period. Further, additional CO2 reduction and O2 generation as a result of photosynthesis are estimated to be 250ton per year respectively whereas biofuel potential was estimated to be 1100gallons per year. Index Terms - Climate change, microalgae facades, net zero building, sustainable building technology.