A novel optimal LQR state-feedback control law is proposed for energy harvesting maximization in regenerative suspension systems where an actively governed electromechanical actuator is used in place of the viscous damper. A special LQR cost function is considered that directly maximizes the electrical power generated by the electromechanical actuator. Other conflicting control objectives, such as ride comfort and road handling, may be considered along with the energy harvesting objective in the proposed control setup, allowing one to directly trade-off among them depending on the application. Specifically, as an example, a condition for trading-off between energy harvesting and ride comfort is added to the optimization problem via forcing a bound on the so called Ride Index. The proposed control law is finally contrasted with other two control strategies usually considered in the literature for energy harvesting applications and is compared in simulative studies via MATLAB and Simulink on a quarter-car model.