The Anaerobic Digester Project

Anyone who has ever seen Back to the Future will appreciate the real life DeLorean this team is in the process of building. At the end of the Back to the Future trilogy, the DeLorean time machine, with the help of the Mr. Fusion Home Energy Reactor, runs completely on household waste. Though the Anaerobic digester won’t take you back to 1955 to attend an Enchantment under the Sea dance, it is aiming to do exactly what the DeLorean did: find a way to turn our waste into fuel.

Anaerobic digestion is a process in which microorganisms break down biodegradable material.  The methane-rich biogas produced means it is suitable for energy production, making it a renewable energy source with the ability to replace fossil fuels. And, what’s more, the nutrient-rich solids and liquids left after digestion can be used as fertilizer. People often confuse anaerobic digestion with composting. So what is the difference? Composting produces mostly carbon dioxide, which has no energy value. In contrast, anaerobic digestion produces biogas with a high percentage of methane, which makes it a great source of fuel, and a possible benefit to urban areas. In addition, anaerobic digestion prefers cooked and oily food waste, as where composting is not ideal for cooked foods or meat. 

Food waste is an increasingly serious issue in the United States. The average American throws away over 200 pounds of edible food each year, with 40% of the food in the U.S. never being eaten. This is particularly bad for the environment because organic waste breaks down and releases greenhouse gasses. Anaerobic digesters alleviate the environmental pressure by collecting the methane that would be released as gas.

Anaerobic Digesters aren’t a new thing; they are used industrially and by farms, but not traditionally in urban areas . The Berkeley team is crafting an Anaerobic Digester fit for residential homes, which is unprecedented. The scaled-down nature is what makes this project unique: because of its size, it extends accessibility to the average household.  

The team is a diverse mix of chemical, civil, mechanical, and electrical engineers, united by their dedication to hard work and sustainability. It was founded in the Fall of 2015 and spent the majority of the semester securing funding. It is solely funded by The Green Initiative Fund (TGIF), UC Berkeley’s Campus Green Fund, aimed at supporting student’s sustainably efforts. Since Spring semester, the project has quickly taken off under the leadership of Tressa Kay Mikel, a junior seeking her Bachelor’s in Chemical Engineering. 

​We are aiming to build a prototype in April to test our system before scaling up to build to the final product for a lucky house on campus.  We are excited to have the chance to use our technical knowledge to have a positive impact on our community, and hope to pave the way for a future where waste is considered a resource.

-Tressa Kay Mikel, Project Leader

Team photo, 2/18/2016. Tressa Kay featured at the far right.
Contact Tressa Kay Mikel at