Stuart, Andrew, Delfino
Evalutation of The Grand Valley Smart Composter
The smart composter 👷🏻♂️💡🌱
The smart compostor was designed by GVSU engineering students to create an automated and educational solution for composting, to provide a less time and labor intensive alternative to traditional manual compost bins.
The composter uses 3 different sensors to monitor temperature, humidity, fill level, and oxygen
It maintains ideal composting conditions automatically by turning on the blowers for aeration and the water pump for moisture whenever sensors detect it falling outside of the set parameters.
Compost is just like recycling, but instead of plastic , it turns organic waste into valuable, nutrient-rich soil (humus).
By diverting food and yard waste from landfills, composting significantly reduces greenhouse gas emissions.
Composting also helps with soil health, improving soil structure, water retention, and reducing the reliance on chemical fertilizers for growing food.
Over the last couple of weeks we conducted a hands on evaluation of the smart composter across 3 different areas,
The first was how novice friendly is was
Composting is very challenging process to get into , not only to build a bin but also to maintain
Effectiveness of the composter
How well did it automate, and how good was it at producing compost
Provide feedback
Give some suggestions for improving the smart composter's design, educational features, effectiveness, and user-friendliness.
Windrow Composting
Static Composting
In-vessel composter (Industrial)
To better understand what makes an optimal composting system, a general analysis had to be made from primary literature in composting research.
Composting Science
C/N Ratio: As a rule of thumb, the C/N ratio i most optimal for composting between 30:1 to 25:1. Too much nitrogen will make the compost smell of ammonia, and too much carbon will make the compost pile lower in temperature.
Microbes: Too much nitrogen promotes denitrifying bacteria's which will take nitrogen out of the system (into the atmosphere) by producing ammonia. Too much carbon allows more nitrogen-fixing bacteria that contribute to making the fulvic and humic acid needed for the humus (nutrient-rich dirt), but then there is not enough nitrogen to make enough of the acids needed to make the humus.
Temperature: The microbes needed for degrading the compost are mesophilic and live in an environment between 20-40 degrees Celsius. A good indicator that high composting activity is happening is a sharp increase in temperature, as the metabolic process to degrade the organic matter is an exothermic process. In an optimal setting, the temperature of the compost could reach around 45 degrees Celsius
Moisture: The microbes are what the whole composting system revolves around to degrade the organic matter into humus. With that being said, all organisms need water to survive, and the microbes are no different. The microbes need enough moisture to survive, but not too or the microbes could be deprived of the oxygen they need. An optimal moisture content was said to be around 40%-65% (Raza et al.).
Composting Systems
Windrow Composting: Large-scale composting method that uses a long and narrow compost pile that can be easily periodically aerated using a tractor with the right equipment.
Static Composting: Normal composting method, compost is left in the composting pile and is left to naturally decompose without any intervention.
Vermicomposting: Uses worms and other smaller organisms that are purposely put into the composting system to help further accelerate the composting process time and ensure better quality by biodegrading the organic matter.
In-vessel composting: An enclosed composter that allows for more control or information over variables like temp, O2, and moisture.
Overall, the smart composter is very advanced with its ability to read data and provide an analysis of what is occurring in it. It does have some kinks that need to be worked out, but overall, as a first-generation product, it is a great foundation to build upon for the second-generation product.
What the composter does best is it gives an accurate temperature reading, which is essential to see if the carbon/nitrogen ratio is in check. As stated above, if it is too cold, it is lacking nitrogen, such as green plant material, and if it is too hot, it is lacking carbon, such as wood chips. Being able to read this data remotely and from the composter's screen is essential for making it easy to keep the composter in check and keep it composting at its most efficient level. It also holds heat well, with it being in-vessel, meaning it is a sealed unit, making it run at greater efficiency.
Since it was made of wood the composter doors tended to swell making it hard to open up
There is currently a lack of acurate measurement of what is going into the composter. The current iteration of the smart composter uses a basic weight scale that is so small that it makes it hard to know the exact weight of what is going into it, as well as to put everything on the scale.
While the smart composter does a lot of things well, after using it, we did have a couple of short-term and long-term recommendations
Short Term
Adding a larger electric tearing scale would make it a lot easier for students and faculty to harvest accurate data on what is going in and what is coming out of the smart composter.
Another suggestion is to make a log to know what is going in and out of the system, and how much
Long term
Add a mixer to the top to help aerate the dirt.
Adding a two-hopper system for carbon and nitrogen material that would automatically dispense material to keep the C/N ratio and fill level at optimal levels.
Possibly add some type of lifeforms to further develop biodegradation in the system. (Earthworms or microbes) These organisms would also provide aeration, like the mixer.
For the second generation of this product, making it out of a different material, such as aluminum, that would not swell like the wood that the current generation is made from.
Why this matters
Promotes sustainability
By diverting organic waste from landfills, we contribute to a reduction in methane
The project encourages public engagement with composting, turning waste from a problem into a valuable soil resource for sustainable agriculture
Encourages innovation
The smart composter is a great alternative to traditional composting
Our feedback contributes to the improvement of the smart composter's design so in the future it becomes more practical and maybe someday something common in peoples backyards
Reflection time
How do you deal with organic waste, has this made you change your views on organic waste and composting.
How can you contribute to healthier soil and reduce food waste
Would you be interested in having your own smart composter over a traditional compost bin?
References
“C/N Ratio-Induced Changes in Predominant Bacteria Affected Carbon/Nitrogen Losses and Humus Synthesis in Composting.” Ying Yong Sheng Tai Xue Bao = the Journal of Applied Ecology, vol. 32, no. 11, Autumn 2021, pp. 4119–28, https://doi.org/10.13287/j.1001-9332.202111.041.
Franciosi, Frank, and Derek Kauneckis. COMPOSTING STATE of PRACTICE: RESULTS from a NATIONAL OPERATIONS SURVEY PUBLISHED 2024 POWERED by SPONSORED BY. 2024, cdn.ymaws.com/www.compostingcouncil.org/resource/resmgr/documents/2024-Composting-State-of-Pra.pdf.
Jahangeer Quadar, et al. “Economic and Quality Evaluation of Composting Technologies.” Elsevier EBooks, Elsevier BV, Jan. 2023, pp. 295–318, https://doi.org/10.1016/b978-0-323-91874-9.00012-7. Accessed 5 Nov. 2025.
Raza, Shahid, et al. “Effect of PH during Composting of Municipal Solid Waste.” Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences, vol. 60, no. 2, June 2017, pp. 114–16, https://doi.org/10.52763/pjsir.phys.sci.60.2.2017.114.116.
“Vermicompost - an Overview | ScienceDirect Topics.” Www.sciencedirect.com, www.sciencedirect.com/topics/agricultural-and-biological-sciences/vermicompost.
Wang, Rongjiao, et al. “The Dynamic Changes of Nutrient and Microbial Succession in Nanomembrane Aerobic Composting of Tomato Straw.” PubMed, vol. 74, no. 3, National Institutes of Health, Sept. 2025, pp. 347–62, https://doi.org/10.33073/pjm-2025-030. Accessed 8 Nov. 2025.