Dear Tee Cee,
I’ve heard often, “Zero waste is a climate solution,” and I think that message needs to get out more because I feel like a lot of people think of it mostly as an alternative to landfills. I get why composting and recycling reduce greenhouse gas emissions, but I’m wondering if there’s a way to calculate and quantify the emissions saved, even for a household, to demonstrate the savings to people?
You are so right that the discussion around the merits of recycling has historically been about saving landfill space, and, while that is a benefit, the value of recycling, composting and zero waste practices is far more beneficially impactful than preventing landfills from filling up. Zero waste is a key climate solution, and there are calculations even individuals or households can make to prove it.
Before we get to how you can measure the climate benefits of zero waste, let’s quickly recap why recycling, composting, reusing and waste reduction are effective ways to fight our climate crisis: The U.S. Environmental Protection Agency calculates that 42% of all greenhouse gas emissions are “consumption emissions” produced from our “stuff” and our food, including emissions produced from the extraction of natural resources, as well as manufacturing, production, transportation, use and disposal.
Recycling, reusing, composting and other zero waste practices significantly reduce the energy needed at every step. So, how do we accurately measure the energy savings of zero waste practices? We calculate by material.
Whether counting the number of glass bottles recycled after a party or measuring the tons of organic waste currently buried in Colorado’s landfills, waste is tangible and measurable. So, for example, we can measure the emissions avoided by weighing each of the different types of materials recycled at the Boulder County Recycling Center or Eco-Cycle’s Center for Hard-to-Recycle Materials. A handy, widely used, free online tool calculates the energy savings of each material by weight.
EPA’s Waste Reduction Model
In 1998, the EPA created the Waste Reduction Model to calculate the environmental impact of waste. WARM works by comparing the climate impacts of different disposal methods. For example, how do the greenhouse gas emissions of landfilling one ton of food waste compare to the greenhouse gas savings achieved if it were composted? Using the WARM model tool, it tells us that composting one ton of food waste saves the equivalent of 68 gallons of gasoline. What about recycling a ton of aluminum cans versus landfilling them? The WARM tool calculates that recycling them saves 153 million BTUs of energy — enough energy to power an average household for a whole year.
The latest version of WARM can calculate the greenhouse gas savings of 60 different types of materials, including organic waste like food, discarded paper and yard trimmings. In addition to comparing the energy savings of different kinds of waste, you can also include economic factors such as wages and labor hours. Recyclers, composters and landfill operators use WARM to better understand their climate crisis impact, which is essential when planning zero waste policies and infrastructure. WARM is free to download from the EPA’s website at epa.gov/warm.
Individual Waste Reduction Model
While WARM is geared toward recycling operators, businesses, and governments, the EPA also has a version of WARM designed for individuals, households and smaller operations, iWARM. iWARM is much more user-friendly and can be downloaded as a Microsoft Excel file. iWARM could easily be used to create environmentally focused math conversion problems. For example, how much energy will be saved if we recycle a dozen aluminum cans? Answer: Enough energy to power a laptop for almost 70 hours. Recycling one steel soup can saves enough energy to power a 60-watt light bulb for 10 hours.
WARM empowers individuals, businesses and governments to better understand the climate impacts of our consumption emissions. How can you use WARM or iWARM to illustrate the link between zero waste and climate change? Please email us your ideas at firstname.lastname@example.org or call us at 303-444-6634.
Have zero waste questions? Want to become a volunteer Eco-Leader? Let us know at Rosie@ecocycle.org.