Brittany Denzer was born and raised in Kona on the Big Island, where she developed a fascination with nature and ecological systems at a young age. She graduated from Kealakehe High School in 2012 and is currently a senior at Colorado College majoring in Organismal Biology and Ecology with a minor in Music. Brittany enjoys spending time outdoors, particularly in the ocean, and spent the last semester conducting research on a sailing voyage from New Zealand to Tahiti through the Sea Education Association. After graduating, she plans to attend graduate school to pursue a master’s or Ph.D. degree in the biological sciences. Ultimately, she hopes to return to the Big Island to apply what she has learned to the challenges facing her island and state.

Home Island: Big Island
High School: Kealakehe High School
Institute when accepted: Colorado College

Carbon Dioxide Utilization Efficiency in Microalgae Systems: Evaluating the Use of Flue Gas to Grow Microalgae

Project Site: Cellana
Mentor: Emily Knurek

Project Abstract

One of the benefits of algae cultivation is the uptake of the greenhouse gas CO2 through photosynthetic processes. Flue gas, exhaust from fossil fuel combustion, is an attractive source of CO2 for algae cultivation because it is abundant, cheaper than conventional sources of pure CO2, and allows for the recycling of CO2 that would otherwise be emitted into the atmosphere. Cellana, a developer of algae- based nutraceuticals, animal feed and biodiesel, is researching and developing an on-site diesel flue gas CO2-sourced system with commercial potential. A previous study showed the flue gas system met design goals, but does not deliver enough CO2 to meet algae growth demand under standard pond inoculation density and duration. This project tested the efficacy of Cellana’s flue gas delivery system supplemented with pure CO2 and provided baseline measurements of CO2 usage throughout the open pond growth cycle. A set of binary ponds were implemented to compare algae grown with flue gas supplemented with pure CO2 to algae grown only with pure CO2. Ponds were grown using Cellana's standard cultivation procedures. Growth rate, biomass productivity, biomass composition, nutrient use, pure CO2 use, pH, and cost were analyzed for the two treatments. An evaluation of the flue gas system including an assessment of its efficacy will be presented. If the flue gas system reduces CO2 requirements and produces quality algae with satisfactory growth performance, expansion of the system could possess commercial viability.