This project will develop the economic case for the adoption of lightweight materials by the wind turbine industry. It will establish the financial benefits and thereby facilitate investment in the development of lightweight turbine systems and structures. The catalyst for the introduction of light weight components is aluminium matrix composite (AMC) material. Comprising aluminium reinforced with continuous alumina fibres, AMC has strength and stiffness properties that exceed those of ferrous metals, at around half the weight. The use of AMC reinforcements, or inserts, within an aluminium casting (termed AAMC) produces enhanced stiffness versus a cast iron part, with no increase in package size. The UK, and CMT in particular, is a world leader in this technology. The technical feasibility of using these advanced materials for weight reduction was established in a Northern Way funded project undertaken in 2010/11. The ‘Lightweight Turbine Gearbox Feasibility Study’ demonstrated weight savings of over 25% in gearbox cast components by replacing cast iron with AAMC. The material is suitable for application to many other turbine systems, in addition to the gearbox. An AAMC component will be more expensive than its cast iron or steel equivalent. However, by decreasing the weight of nacelle components, the costs of towers, installation and transportation will reduce, lowering the capital and operational costs of wind farms, particularly those offshore. Operational savings will be achieved via improved durability and reliability. Generation of the economic case for weight reduction must include all of these factors, analysed to identify the cumulative cost savings for the wind farm operator and the returns on investment for the system supplier and turbine manufacturer. The project will identify the system that will benefit most from the use of AAMC, in terms of weight reduction and functional improvement, so as to provide a target for future product development.