The full lifecycle greenhouse gas emissions of an energy carrier, combining upstream fuel extraction and operational vehicle combustion.
Well-to-Wheel (WTW) represents the total lifecycle climate impact of vehicle transport. It is the sum of Well-to-Tank (WTT) emissions (energy extraction, refining, production, and distribution) and Tank-to-Wheel (TTW) emissions (direct combustion inside the vehicle's engine).
Serves as the mandatory primary emissions metric in TrustedTrucks. All carbon foot-printing, insetting claims, and carrier rankings evaluate WTW rather than just tailpipe (TTW) emissions to ensure fair comparison between diesel, HVO, bio-LNG, and battery-electric trucks.
WTW = WTT + TTW. For diesel: WTW factor ~3.24 kg CO2e/L (WTT: 0.60 + TTW: 2.64). For battery-electric: TTW = 0, but WTT reflects regional grid carbon intensity.
Zero tailpipe emissions (TTW = 0) must never be advertised as 'zero emissions' without declaring the upstream WTW electricity generation footprint.