Solutions to cost-effective business development opportunities in renewable energy will come through the integration of emerging technology and innovative applications. This is especially valid for the successful development of small wind energy development (up to 100kw capacity). Technological advances in wind energy have focused on large wind (in excess of 100kw capacity) resulting in lower capital costs at $3,000 per kw capacity and output costs of nearing $.10 per kWh. There have been significant advances in blade design, utilization of composites in manufacturing, new direct-drive generators (specifically RFG), yaw / steering / breaking improvements and improved designs in towers. Engineers have been quick to integrate technological advances to keep up with accelerated demand and growth in “large wind” both domestically and internationally. Small wind on the other hand, has not benefitted from the development and integration of technological advances with capital costs remaining at $5,000-$7,000 per kw capacity and output costs of $.20-$.30 per kwh. Small Wind Turbine design has not benefitted from strong technological advances with dependence on 20 year old gear-driven wind turbine technology. Limited advances have been made in vertical axis wind turbines (VAWT) technology but nothing that has been adequately validated or has had significant market penetration. Generator technology has had limited technological innovation in the last 20 years beyond the integration of permanent magnet designs. As a result, expectations of small wind have far exceeded operational realities and ROI.
With global demand for small wind energy development at the base of a projected steep curve for the next 10-20 years, there is an industry “call to action” to support the development of emerging small wind technology and further to fully integrate technological advances and innovate practical applications in order to respond to significant business development opportunities. The introduction of the radial flux permanent magnet generator design provides for a strong initial step in this direction by achieving increased output from small wind turbines at reduced capital costs and operating costs. The Small Wind Turbines, LLC (SWT) RFG generator technology has taken on even more importance to small wind development with the innovation of direct drive utilization. The SWT-RFG radial flux design is unique with a dual stator, essentially a generator within a generator. Compared to other permanent magnet generators there is more copper and less magnetic material The SWT-RFG utilizes 40% fewer active components, has 40% less weight and is projected to have price 35%-45% less than competing generators. Dr, Longya Xu, Professor of Electrical Engineering, Ohio University, stated in his technical assessment of the GMI RFG (2009), “the double stator and dual air-gaps result in a 2x increase in the interactive area of the generator between the stationary and rotating components producing a higher density ratio watts/cubic inches.”