The definition of energy is a long-standing difficult problem in gravity theory because of the diffeomorphism invariance of the gravity field. Various approaches have been developed. We have generalized Wald’s approach for the constructing quasi-local energy of gravity field, which is based on the Lagrangian formulation, to the three-dimensional gravity with torsion, and obtained the conserved energy and angular momentumfor the Mielke-Baekler (MB) model. For BTZ black hole with torsion, the conserved charges are consistent with those obtained from the approach based on Hamiltonian formulation.
