Appropriate Technology Product Development Big need – 90% of world’s designers currently work for 10% of world’s rich population. Design for the Other 90% is a movement to reverse this; and is close to EMI’s DNA. We recognized last year there is lots of room for EMI to grow in Appropriate Technology expertise, and then through Don and CJ, in AT product development. So this Wedge Project is EMI’s first ever Appropriate Technology Product Development project. Excited to partner with Don & CJ in this. Expecting to make a few mistakes as we figure this out together.

Needs & Potential Needs Only 2-5% of rural Sub-Saharan Africa served by electric grids 1.6 billion people in developing countries currently live without electricity International Energy Agency (IEA) estimate that by 2020 developing countries will need to double their electrical power output Potential 4 million estimated micro-hydro locations worldwide 100,000 family size micro-hydro units in Vietnam Estimated 100,000 household sites In Philippines There is a huge need for Electrical Power worldwide, and a huge Potential as well.

History Invented by Don in Liberia Originally a Surf Model River Model Adaptation EMI Involvement Existing Prototype Performance – 178W maximum at 60 RPM Invented by Don in Liberia – on EMI trip despondent over poverty of LIberia. Sitting on beach. Lord say “Harness this power for the people” Originally a Surf Model – ran into environmental hurdles trying to develop it on West Coast. River Model Adaptation – with CJ’s involvement, turned to River Model bc less environmental hurdles and still broad potential. EMI Involvement – Don came to EMI fall 2010 to share what he developed, then we hit on idea of EMI team to help develop further. Performance – peak performance of river model was 178W maximum at 60 RPM in Navigators Glen Eyrie Camp Creek.

Ultimate Goals Ultimate User: Poor rural household in developing World Desired Characteristics Affordable – for rural farmer making $400/yr Reliable & Durable – 24 hours/day for up to 3 years. Debris protection Simple – easy to install, maintain and replace by poor rural developing world farmer Safe Secure – resistant to theft and vandalism Environmentally Friendly Modular – for scalability Technical Requirements: Stream Flow of 5-20 ft3/sec Power > 300 watts – enough for lights, cell phone, computer Ideal Cost < $100 (production model in developing world hopefully produce power for < $.08/watt Purchase Plans: 3 year loan payback. Business charging cell phone batteries, etc. Other Potential Models: Backpacker – smaller Villager – larger or linked household models Municipal – for North American municipalities: power or lighting for parks

Summer 2011 – Wedge 2.0 Refinement Goals More efficient prototype: > 300 watts Elegant design for future manufacturing simplicity Cost < $500 (parts only) Method: EMI Design Intensive – this week April 19-22, 2011 Wedge 2.0 Fabrication - till end of May Summer testing – throughout summer Colorado Springs Utilities (CSU) graciously interested CSU/FMDC requirements – Ultimate requirements, plus especially safe and environmentally safe Not interrupt flow, normal operations or cause erosion. Emergency removal capability.

Existing Wedge Dynamics Impeller tilted allows for greater diameter, which equals more power Converting velocity to head Hydraulic Jump Effect RPM Existing Wedge Prototype Peak Performance: 178 watts at 60 RPM (Glen Eyrie Camp Creek)

Hydrodynamic Modeling – Existing Wedge

Hydrodynamic Modeling – Housing Options Best: Option 4 “Open Arms/Hugging”: increases velocity 13% over straight tube  40% power increase

Environmental Concerns and Anchoring Environmental Concerns to address Wildlife – bears, birds, etc. Little to no impact Fish – Sediment/ Fish habitat. Little to no impact Emissions – leaching of materials. Little to no impact Shield Design “Trash Rack” type design to divert debris and fish around wedge Anchoring Anchoring device integrated with shield for additional stability

Turbine Design – Turbine Dynamics Relative Velocity Angle of Attack Variable Pitch Direct Drive Eliminate gearing loss and maintenance

Electrical Design Challenges Low Torque (5-15 N-m) Low Speed (300-800 RPM) Wet environment Remote access Inexpensive Selected Design Direct drive Permanent Magnet Generator Custom low-speed design

Ultimate Design – Custom PMG Improvements: Tube more efficient hydraulics Wings capture more flow Direct drive eliminates pulley losses More efficient turbine Better generator Result: 300 watts (we hope)

Wedge Team Wedge Team (from L to R): Don Sternitzke (Wedge Inventor), Andy Engebretson (Elec. Eng), Pat Godsell (fabricator), Darryl Byle (Mech Eng), Calla Suen (Envir. Eng), CJ Anderson (Wedge Co-Founder), Tim Godsell (Fabricator), Sam Loomis (Mech/Elec Eng), Phil Harshaw (Mech Eng), Steve DeLory (Elec.Eng), Craig Hoffman (Civil Eng), Steven Kwan (Hydrodynamic Eng), Chris (Fabricator). Not pictured: Mark Hopewell (Civil/Mech Tech) Front Row: Proposed Wedge 2.0 Culvert Housing, Existing Wedge Prototype

Appropriate Day for Appropriate Technology Fitting day to be presenting the Wedge as it is not only Good Friday but also Earth day. Fitting because the Wedge is intended to both bring renewable power for the world’s poor, but also to be a leading edge for the gospel. Good Friday Earth Day