Satellite based fire radiant energy retrievals are widely applied to assess biomass consumed and emissions at regional to global scales. A known potential source of uncertainty in biomass burning estimates arises from fuel moisture but this impact has not been quantified in previous studies. Controlled fire laboratory experiments are used in this study to examine the biomass consumed and the radiant energy release (Fire Radiative Energy, FRE, (MJ)) for western white pine needle fuels burned with water content (WC, unitless) from 0.01 to 0.14. Results indicate a significant relationship: FRE per kilogram of fuel consumed = −5.32 WC + 3.025 (r2 = 0.83, n = 24, P < 0.001) and imply that not taking into account fuel moisture variations in the assumed relationship between FRE and fuel consumed can lead to systematic biases. A methodological framework to derive a revised formula that enables the estimation of biomass consumed from FRE, which explicitly takes into account fuel water content, is presented.