Closing the Carbon Loop: Growing Algae Using Sustainable CO2 from Bio-waste

EPA Grant Number: SU833931
Title: Closing the Carbon Loop: Growing Algae Using Sustainable CO2 from Bio-waste
Investigators: Venable, Mark E. , Porras, Erica , Ramsdell, Jeff
Institution: Appalachian State University
EPA Project Officer: Page, Angela
Phase: I
Project Period: August 15, 2008 through August 14, 2009
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2008) RFA Text |  Recipients Lists
Research Category: P3 Challenge Area - Air Quality , Pollution Prevention/Sustainable Development , P3 Awards , Sustainable and Healthy Communities


Record oil prices, poor air quality, and the threat of global warming have resulted in renewed interest in micro algae for its great potential as a biofuels feedstock. However, research is predominantly focused on growing algae with coal flue gas, and extracting the algae oils for transesterification into biodiesel. This method does not close the carbon loop, and the negative environmental and health implications of fossil fuel mining and extraction persist.


The purpose of this project is to build a sustainable algaculture facility in the Appropriate Technology program at Appalachian State University. The system will be a pilot scalable system utilizing sustainable designs developed and promoted by the ASU Appropriate Technology program for over 20 years.


The research focus will be three-fold – (1) explore anaerobic digestion of bio-waste as a renewable CO2 source for algae growth, (2) collect and quantifying community bio-waste for anaerobic digestion, (3) and study and optimize algae cultivation. Innovative objectives of the project are to design and build a low cost algae photobioreactor with minimal energy inputs, utilize a passive solar green house (already built) with solar thermal technology for algae growth, incorporate an anaerobic digester for diverting bio-waste from the landfill to produce methane, and recover the CO2 by combusting the methane and diverting it to the algae. In addition we will distribute bio-bins to local restaurants and households to quantify the pounds of waste collected to sustain the system.

Expected Results:

Results will be measured by tracking algae growth rates and oil content, the CO2 and energy production from the anaerobic digester, and the quantity of bio-waste collected from the community. Energy inputs will be monitored for energy balance calculations. In addition, a full fuel production cost analysis will be performed. This project meets the P3 requirements of people, prosperity, and the planet because it increases the environmental benefits of algaculture, provides a cleaner fuel alternative to petroleum diesel and fuel oil, involves educating the community about responsible waste separation, promotes a distributed fuel production model for improved local economies (applicable to the U.S. and the developing world), and incorporates an interdisciplinary team of students and faculty (Appropriate Tech, Sustainable Development, Chemistry, Biology). This project will continue to provide hands-on research opportunities for students and provide faculty a real-life demonstration and educational tool for integration into the curriculum.

Supplemental Keywords:

Biogas, bio-based feedstocks, anaerobic remediation, renewable feedstocks, waste to value, energy recovery, Global climate, innovative technologies, waste reduction, atmosphere, cleaner production/pollution prevention, renewable fuels, petroleum, Environmental Engineering, alternative energy source, alternative to petroleum diesel fuel, waste minimization, sustainable infrastructure design,, RFA, Scientific Discipline, Sustainable Industry/Business, POLLUTION PREVENTION, Sustainable Environment, Energy, Environmental Chemistry, Technology for Sustainable Environment, Environmental Engineering, sustainable development, environmental sustainability, alternative materials, biomass, alternative fuel, biodiesel fuel, energy efficiency, energy technology, alternative energy source

Progress and Final Reports:

  • Final Report