This article presents the results of an 11-year field experiment (2008-2018) conducted in Poland to investigate the biomass yield and energy efficiency of fodder galega (Galega orientalis Lam.) in high-input and low-input production technologies. The demand for energy in the production of fodder galega biomass ranged from 13.0 to 14.2 (year of plantation establishment) to 6.4-8.2 GJ ha (years 2-11). Agricultural intensification increased energy inputs by 11% on average. Dry matter yield (DMY) and energy output peaked in years 4 and 5 (14.7-15.3 Mg ha and 122.4-131.1 GJ ha, respectively). In the high-input production technology, DMY was 0.62 Mg ha higher, energy output was 4.9 GJ ha-1 higher, the maximum DMY was achieved one year later, and the rate of decrease in biomass yield and energy output in the last years of the experiment (years 9-11) was 30% lower in comparison with the low-input system. The energy efficiency ratio of fodder galega ranged from 2.28 to 2.42 (year 1) to 8.04 -16.53 (years 2-11). Productivity was 4% higher in the low-input than in the high-input technology. Fodder galega biomass was characterized by higher energy efficiency in the high-input technology (by approx. 2-12%) only in the last years of the experiment (years >= 10). (C) 2020 The Authors. Published by Elsevier Ltd.