Pallets as biomass fuel
Ground pallet wood can be burned in boilers for heat or power. EPA does not count this as recycling; it reports wood packaging combusted with energy recovery separately (1.65 million tons in 2018). WARM credits combustion of dimensional lumber at −0.58 MTCO2E per short ton, almost all of it from displaced utility electricity (Exhibit 12-13).
How EPA counts it
EPA's 2018 wood packaging figures split 11.53 million tons generated into 3.10 million recycled, 1.65 million combusted with energy recovery and 6.78 million landfilled (EPA). Fuel use falls in the combustion line, not recycling.
The WARM factor
WARM's combustion factor for dimensional lumber is −0.58 MTCO2E per short ton (Exhibit 12-3). Exhibit 12-13 breaks it down: 0.01 for transport, 0.04 for nitrous oxide, and −0.63 for utility emissions avoided by the electricity generated. CO2 from burning the wood itself is biogenic and excluded (WARM v16, ch. 12).
WARM's combustion factor assumes a waste-to-energy plant generating electricity. A wood boiler making process heat may displace a different fuel, so treat the factor as an approximation and say so.
Does it count as diversion?
Programs differ. Some count energy recovery as diversion from landfill and some do not. The Pallet Fate Report has a switch for it; check the rule of whichever program you report to. See diversion rate.
Sources
- Containers and Packaging: Product-Specific Data (wood packaging, 1960–2018) U.S. EPA. Accessed October 27, 2026. Page last updated October 19, 2026; latest data year 2018.
- Documentation for Greenhouse Gas Emission and Energy Factors Used in WARM, Version 16: Construction Materials Chapters, ch. 12 Wood Products (EPA-530-R-23-020) U.S. EPA. Accessed October 27, 2026. Exhibits 12-3 (p. 12-3), 12-9, 12-13, 12-15 and 12-16 (p. 12-10).