Energy Harvesting via Ballonet Altitude Control; Sustainability of Renewable Energy

Renewable energy is not perfect and as a society, we need to critically evaluate the ways that we use and generate energy. Renewable energy alone will not solve our energy crisis. In my capstone we explore the possibility of energy generation from the movement of a blimp, taking the energy of movement from a process that is already happening and determining if energy from it can be captured and used. In my STS research paper I am looking at the differences between renewable and sustainable energy. Renewable energy is an improvement over fossil fuels but to become sustainable, we have to look further into the implications of energy generation. These are connected because one way to move to more sustainable practices is to improve on the systems we have in place, whether this be increasing efficiency, harvesting energy to use at a later date, reducing emissions etc.
In our capstone, we were given the problem of demonstrating the feasibility of using a propeller that is made to turn due to the relative flow of the surrounding air as the airship rises or falls to charge a battery onboard the vehicle during the ascent and descent of the airship. This would allow us to harvest energy from the movement of the airship which would otherwise go to waste. In developing this project, we quickly discovered that at the scale we would need to do it at, any weight we added onboard the airship would make it difficult to fly and change the buoyancy with the ballonet. So, we pivoted to having the airship be tethered on a frame so we are able to use pulleys to allow us to isolate the movement due to the balloneet to determine if you can then generate energy through the pulleys instead of propellers.
Using this method, we were able to create an airship that would move up and down and we created a small amount of energy from the pulleys. We had the pulleys wrap about a small motor that we then used as a generator. We attached the generator to a breadboard that is hooked up to measure voltage to determine if we could measure voltage from it. We ended up getting a very small amount of voltage generated from the pulley moving, but most of the pulley movement came from counter weight issues and friction rather than the movement of the balloon under the power of the ballonnet. Through calculations it was determined that we would have to make it much larger for us to get significant lift to move on its own and spin the motor.
In my STS paper, I explore the idea of renewable vs sustainable energy. While the push for renewable energy is beneficial, it can have many problems, and as a society we must strive for sustainable energy generation instead so we take into account our energy generation needs now but also the needs of the future. Renewable energy is far from perfect. It can produce a large amount of energy on install, negatively affect the environment around it, and battery components from it must be mined and then recycled which can have large consequences.
To look into this problem, I looked into the results of my capstone as a case study for how energy harvesting can be implemented to make the current system more efficient. I conduct a literature review through the responsible research and innovation lens to see how renewable energy is better than fossil fuels but also the negative impacts it can have and how to negate it. There are many different ways that more sustainable energy generation practices are being implemented, and the long term consequences are increasingly being looked into.

School of Engineering and Applied Science

Bachelor of Science in Mechanical Engineering

Technical Advisor: Frank Lagor
Technical Advisor: Michael Momot
STS Advisor: Pedro A. P. Francisco

Technical Team Members: Clarisse Forro, Vivienne Hughes, Troy S. Meink, Robert Stambaugh, Will Stevens, Richard Yau, Yining Xu