Student Compost To Heat Chilly Vermont Greenhouses

Students this year at the University of Vermont chose to see if they can heat their greenhouses with their dining-hall’s composted food scraps.

The very green and progressive University of Vermont generates its own Clean Energy Fund every year, with a $10 fee levied on all its students each semester. The university encourages its students to submit their own ideas for renewable energy related sustainability projects to use the funds. Nearly $102,000 will be awarded to the selected projects, pulling from the $225,000 generated each year for the fund.

Responding to a student interest in composting as an energy source, two of the awards this year will look at ways that the heat generated by composting can be used to heat the campus greenhouses in Vermont’s chilly winters.

image via UVM

Clean Greenhouse Energy at Miller Farm: This project will meet some of the heating needs as well as address the treatment of wastewater at a clean energy greenhouse. A first phase – feasibility and design – project will look into compost heat as an agricultural energy source for a combined research and production greenhouse at Miller Research Farm.

Compost Power for Slade Hall Greenhouse: This project involves composting onsite and providing a source of heat for an existing greenhouse structure at Slade Hall. In addition, it will produce organic compost as a byproduct for on-farm use and support student internships on-campus.

Compost for the projects will be sourced from the school dining halls as well as from yard waste. It helps that the university has a good food scrap collecting system in place. Students are asked to separate their food scraps for composting in all dining hall locations. and an “Eco Monitor” takes care of keeping the carts and buckets clean, keeping the carts from freezing solid in winter, and from stinking too badly in summer.

Currently, UVM does not have any large-scale compost sites on campus. It contracts with a private hauler who collects food scraps from all dining locations five days per week and trucks it to a non-profit composting operation near campus –  a popular place for students and classes to visit and learn about the composting process.

According to each semester’s “weight audit” – where the truck operator weighs all UVM food waste separate from other customers on the route -the university diverts 7.93 tons of food scraps per week to the composting operation. During fall cleanup, the college’s grounds department also keeps track of how many cubic yards of leaf and yard waste are hauled to the composting facility.

With nearly eight tons a week in compostable food scraps – plus the considerable leaf and yard waste – the university will likely be able to generate quite a bit of heat in the process of composting. So using composting on-campus for greenhouse heating – rather than sending out their waste for off-site composting and paying for power – makes a lot of sense. It will be interesting to see the results.

Susan Kraemer enjoys writing to publicize the many great solutions for climate change that we can find if we just put our minds to it. She covers renewable policy and clean energy for CleanTechnica and GreenProphet and green building at HomeDesignFind. She recently moved home to Waiheke Island where her writing is now powered by the 80% renewable electricity that powers New Zealand.