The present invention is a method and apparatus by which power is controlled in a hybrid electric vehicle such that high levels of performance and efficiency are realized. The present invention includes a method and apparatus developed to optimize the use of energy in a hybrid vehicle application from the hybrid energy storage device. The method and apparatus of the present invention is particularly useful with energy storage devices there the energy state, such as the state of charge, is readily determined by an easily measured attribute. Ultracapacitors and hydraulic storage cylinders are examples of the types of energy storage devices to which the present invention may be applied.