Wave energy convertor (WEC) offers the potential to revolutionise power production globally. WEC harnesses the enormous renewable energy presents in our oceans waves and converts it into two of the most valuable commodities underpinning the sustainable growth of the planet; zero-emission electricity. Heave Buoy Wave Energy Convertor is a wave-energy technology that converts kinetic energy from ocean swell into electrical power. This Unit will incorporate subsea electricity production, power take-off (PTO) which uses subsea cables to connect to an onshore substation. The PTO will be contained inside the buoy that will eliminate the tendency of the pumps, accumulators and other hydraulic components attached to the seabed. This also reduce installation and maintenance time and cost as the entire WEC Unit can be towed to shore for any routine maintenance required.