What is an energy balance and how is it related to material balance?

An energy balance accounts for all energy entering, leaving, and stored in a system: Energy In + Heat Added = Energy Out + Work Done + Accumulation. For steady-state: sum of inlet enthalpies + Q = sum of outlet enthalpies + W. Energy balances are linked to material balances because: flow rates from material balance multiply with specific enthalpies, compositions affect enthalpy calculations, and phase changes determined by material balance affect latent heats. Energy balances are used to size heat exchangers, heaters, coolers, and calculate utility requirements. Always complete material balance first as it provides the flow rates needed for energy balance.