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Carbon Footprint

The Carbon Footprint of Rendering

For each metric ton of CO2 produced by operating rendering plants, 7.19 metric tons of CO2 are removed from the environment.

  • Renderers are credited for removing large amounts of carbon from environment:
    • Fat is more than 75% carbon
    • Protein meals are about 25% carbon
    • Each pound of carbon can result in an environmental release of 3.7 lb CO2
    • If not rendered, these materials would be a potential source of green house gases such as CO2 and methane
    • The global warming potential of methane is 23 times greater than CO2

If not for rendering in North America, 59 billion pounds of biological materials would be land filled, burned, buried, or inappropriately dumped with huge amounts of carbon dioxide, ammonia, and other compounds ending up in our air and water. When rendered, these products are dried, stabilized, and recycled for feed and energy.

  • Rendering is a green industry protects the environment by collecting and recycling animal byproducts and mortalities, which will harm the environment if allowed to decompose.
  • Rendering is a recycler of bioenergy, protein, carbon, phosphorus and other biological resources.
  • Rendering provides essential services to protect human and animal health from disease and protect the environment.

The Main Numbers

A typical1 rendering operation processes one million pounds of raw materials in a 24 hr. period.

During that day, the plant…

  • Uses 9998 therms of natural gas
    • 0.005 metric tons of CO2 are produced for each therm used
    • 49.9 metric tons of CO2 are produced each day from natural gas
  • Burns 616 gallons of its own fat as biofuel
    • 0.01 metric tons of CO2 are produced for each gallon (similar to fuel oil)
    • 6.77 metric tons of CO2 are produced each day from biofuel
  • Produces a total of 56.76 metric tons of CO2
    **(0.127 lb CO2 for each pound of material rendered)
  • Removes a total of 408.17 metric tons of CO2 from the environment per day
    (0.914 lb CO2 for each pound of material rendered)

What If Such Materials Are Not Rendered?

  • Renderers collect putrescible animal materials and use heat processes that removes water, which reduces volume 50 to 70%, and kills pathogens to produce protein rich meals and fats that are stable and safe.
  • Decomposing material contributes green house gases, such as CO2, methane & nitrous oxide.
  • Decomposing material increases eutrophication & acidification potentials from PO4 & N2O
  • Decomposing material increases human and animal disease reservoir
  • Decomposing material causes odor
  • Decomposing material attracts scavenger animals and insect pests
  • Disposal in landfills displace other materials

Carbon Dioxide Balance Graph

Few industries have such a small carbon footprint while having such a positive impact on the environment.

1 Many things would make a particular plant better or worse than this model. More efficient operations use less fuel, bigger operations have more throughput, and management greatly impacts energy conservation. The drive to save money and use less fuel improves the carbon footprint of this and every other industry. Renderers diligently conserve every unit of energy possible. The blend of fuels described in the “typical” plant reflects industry averages and any one plant may burn a blend or all one fuel or another.


Data on rendering plant energy use and throughput are compiled from proprietary unpublished data from NRA members.

Conversion rates of carbon into greenhouse gasses are from an EPA site found here.