Patent ID: 8038383

Claim:
A vertical axis turbine comprising: a base, and a turbine rotor rotatable relative to the base about a vertical axis of rotation; wherein the turbine rotor comprises: at least one inclined elongate aerofoil or hydrofoil spar mounted at a lower end thereof to the base and inclined upwardly and outwardly from the vertical axis of rotation, and each of said at least one spar having mounted thereto at least one aerofoil or hydrofoil section blade, wherein each of said at least one aerofoil or hydrofoil section blade is inclined downwardly and outwardly relative to the vertical axis of rotation, and wherein each of said at least one aerofoil or hydrofoil section blade is angled relative to a respective one of said at least one spar to reduce an overturning moment when the turbine is rotating in a fluid flow.