Vertical axis wind turbines have experienced a renewed impulse during the last few years, with important research efforts focused on them. This work is focused in the development of new blade designs capable of notably reduce their manufacturing cost and, consequently, improve global profitability. Thanks to the aerodynamic and structural analyses that have been carried out, a final blade design has been achieved. It is based on the use of hydroforming manufacturing techniques with metal sheets, creating 3 meters blades to be used in a turbine capable of produce about 1kW. First estimations show that with the positive effects of a mass use and production (economies of scale), such metal blades have a 90 % reduction potential in their production costs compared to fibre-reinforced ones for single turbines.