One person’s trash can be an engineer’s treasure

“I was looking for design experience beyond class,” said Matt McGarry. “I wanted extra experience and this opportunity jumped out at me. I have the chance to work on something that I’m interested in and I think is good for the future.”

The opportunity that McGarry references is a senior design project within the department of Mechanical Engineering. He is part of a ten person team that is designing and building a mobile biogas-to-energy module that will be used to demonstrate and promote renewable energy production. The goal is to build an anaerobic digestion/biogas-fueled power production process that is simple, attractive, well-engineered and cost-effective.

With a growing focus on sustainability in engineering, this team of engineers, comprised of two civil engineers, McGarry and Lilly Nguyen, and eight mechanical engineers, want to find a sustainable way to handle waste. They are working on a completely mobile renewable energy process that brings food waste in and puts electrical energy and nutrients out.

The team will spend two semesters working on a combined heat and power process fueled by biogas from an anaerobic digester. Through anaerobic digestion, microorganisms are used to break down organic material in the anaerobic environment. Once that happens, organisms convert the waste into biogas, which is made up of 50-70% methane. Methane is one of the most potent greenhouse gases and contributes greatly to global warming. By capturing and utilizing biogas, it will efficiently reduce methane emissions into the atmosphere.

McGarry and Nguyen will design the anaerobic digester and ensure that it operates and produces gas. The digester will use kitchen waste from Turner Place dining hall on campus. The mechanical engineers will then take the biogas and run it through an internal combustion engine to power a generator that produces electricity.

“We are taking something that most people would look at as garbage and turning it into something useful,” said McGarry. “I want to be able to demonstrate that this is a viable option going forward to use this sort of technology. It works and it is a practical application for a lot of different industries.”

Those industries that could benefit from this process include businesses and factories such as dairy, swine or poultry farms, wastewater treatment plants, landfills, or other factories that are producing organic waste.

“The whole idea is not looking at this waste as actual waste, but as something that has potential you can work with,” said Clara Eichler, CEE faculty advisor to the project. “In this case, we are producing fuel.” In fact, benefits to using biogas-to-energy processes can create renewable energy, reduce waste disposal costs and improve nutrient recovery.

Beyond the design and implementation piece of the project, one of the objectives is to be able to demonstrate this process to potential clients. As a scaled down version of an industrial-sized process, they will be able to move the digester on a trailer to demonstrate to the public and to potential clients and to everybody who is interested in sustainable approaces to generate electricity. They have even started brainstorming ways to demonstrate the electricity output to clients, including hooking up things like a popcorn maker, a dryer, or a phone charger.

McGarry and Nguyen will also gain professional experience working on a project similar to one they may encounter in their future careers. “The neat thing about this project is that they think of it from start to finish,” said Eichler. “It is a great experience for the students to work on a real, practical project.”

McGarry agreed and stated, “It is cool to learn the theory in classes and then get the chance to put it to work. It is a good way to see your education come together and how it will help you in the future.”

The next time you leave half of your plate of food at Turner Place, you can rest assured knowing that you are providing waste for research that could significantly increase the sustainability of fuel production.