The stability and power conversion efficiency of a wave energy converter (WEC) which includes a float, a spar and a power taken device (PTO) connected between the spar and the float is increased by connecting a heave plate to the spar in a very secure manner and by carefully limiting the movement between the float and spar to one direction (i.e., up-down motion). Buoyancy chambers may be attached to the WEC to facilitate its transportation and deployment. The WEC may be formed in sections and assembled at, or close to, the point of deployment.