2023-2024 Challenge 1st Place – University of North Carolina at Charlotte

Team Members:

Ankit Soni – Master’s student in Applied Energy and Electromechanical Engineering

Emilio Nava – Undergraduate in Mechanical Engineering

Felix Ekuful – Master’s Student in Construction and Facilities Engineering

Harriet Darkwah – Undergraduate in Applied Energy and Electromechanical Engineering

School: University of North Carolina at Charlotte

Challenge: You and Me, Carbon Free!

Problem Definition: The objective of this challenge is to develop an innovative solution that will reduce carbon emissions from U.S. buildings (residential or commercial, new or existing). Problem statements can address embodied carbon emissions and/or operational carbon emissions. Innovative solutions should lead to significant reductions in carbon emissions and increased affordability for identified stakeholder groups to obtain new technologies.

Project Title: Building-Integrated Algae Photobioreactor Systems for Carbon Sequestration

Solution: Carbon dioxide related emissions account for 76% of greenhouse gasses. As a process to capture and fix atmospheric CO2, carbon sequestration is an important method to reduce global climate change. This proposal explores an approach to mitigate carbon dioxide emissions utilizing microalgae in a photobioreactor (PBR) system integrated with building HVAC systems. Through the process of photosynthesis, the algae efficiently sequesters CO2 from the flue gas or exhaust air of buildings, yielding fresh oxygen and biomass. Furthermore, the investigation involves researching the characteristics of Chlorella vulgaris, such as its lighting consumption and growth rate. Our literature research reveals that a single photobioreactor, with a Chlorella vulgaris to water ratio of 120g/20L, can sequester approximately 3.2 kg of CO2 per hour while producing 1.3 kg of biomass daily in optimal conditions. The PBR system can be easily scalable in terms of both the number of installations and the system size. This innovative solution offers a promising approach to sequester CO2 due to building operation and simultaneously produce a sustainable source of biomass.