SBIR Phase II:High Performance Microalgae Building Enclosures for an Energy Efficient Retrofitting Application

The broader impact of this Small Business Innovation Research (SBIR) Phase II project is in enabling an energy-efficient and cost-effective solution for a healthy, sustainable built environment. Stringent environmental protection policies are presenting the building industry with challenges in reducing environmental impacts. High performing windows could play an role in reducing energy use and pollutant emissions. Creating a window system that reduces building energy consumption and carbon dioxide (CO2) emissions may have broad societal, economic, and commercial impacts. The proposed biochromic windows can serve as an alternative, energy efficient retrofit and help meet net zero energy, net zero carbon buildings. Their multiple environmental, economic, and social benefits include high energy efficiency, improved air quality, carbon capture, and renewable energy production. Energy efficient window retrofitting accounts for over 60% of the global window market share. In 2021, the global window market grew to $10 billion for replacement and renovation and $6 billion for new construction with a compound annual growth rate of 8.6% and 8.3% respectively. This energy efficient, carbon sink technology may result in 20~30% energy savings and carbon reductions. The good air quality further benefits occupant health and well-being, making the building more appealing to occupants, industry professionals, and stakeholders.The key technical innovation of the biochromic window is to integrate biological cells within a window assembly for commercial building retrofitting applications. As a primary building enclosure system mediating between indoor and outdoor environments, the biochromic window offers improved insulation, dynamic shading efficacy, daylight penetration, views to outside, carbon dioxide (CO2) biofixation, and biomass production, all of which are attributes of improved building energy efficiency, good indoor air quality, beneficial carbon sequestration, novel biofuel production, and user satisfaction. The primary project objectives are to: 1) prototype of a biochromic window, integrated with an intelligent control system to enable the maximum performance; 2) conduct performance testing and obtain performance certificates; and 3) scale-up mass production manufacturing and carry out technology demonstrations at early adopter’s buildings. Project outcomes seek to save building energy consumption in heating, cooling, and artificial lighting load while producing on-site renewable energy and sequestrating CO2. The biochromic windows, coupled with an intelligent control system, further enhance economic and environmental performance depending on solar intensity and carbon concentration. The view-out area within the biochromic window admits year round daylighting. Proximity to green nature is expected to provide aesthetic quality and emotional comfort for user satisfactions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.