There is a considerable amount of available, but so far generally unused energy in rivers, streams and man-made channels, particularly at very low heads of less than 10. Unfortunately, this resource is disseminated across thousands of locations, each with different head, flow, and site conditions. An affordable technical solution is needed to allow the widespread exploitation of this clean, renewable energy asset. Proposed solution: This proposal is about developing a system that is flexible enough to be site specific, yet uses as many common components as possible for lower cost. The vision is an integrated turbine/generator system including: 1) a rim electric generator; 2) a 3D printed turbine; and, 3) a ducted conduit, also 3D printed or with 3D printed inserts mounted on a generic frame. The rim generator, with a rotor placed at the periphery of the turbine runner (hence the name rim generator) and a stator set into the ducted conduit allows the system to be in line with the flow of water. This configuration, without elbows in the channel, makes full use of the limited head available and is therefore particularly well suited for very-low head sites. 3D printing of the runner, inlet and draft tubes makes for site-specific, efficient designs. The ducted conduit focuses the water towards the turbine blades. The overall design is expected to be compact, can be manufactured off site and placed as a single unit into the water for easy installation and maintenance. Commercial applications and
Benefits: This modular, scalable turbine/generator system is an important stepping stone towards obtaining the level of cost per kWh of energy that will make small hydro power available for harvest on an economical scale. The system, further refined in Phase II, is expected to be aimed first at man-made systems (water conveyance plants, water-intensive industries) as well as smaller dams in need of refurbishing. Addressing these markets first will provide the economies of scale needed to further expand into very-low head sites across the board.
Keywords: Small hydro, micro hydro, very-low head, renewable energy, integrated turbine-generator, rim generator, 3D printing, additive manufacturing.
