1. Potential Design Outreach (DO) Involvement
Nov 14, 2014 + ?
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.

2. Agenda
Design Outreach Intro – Greg (5 min)
Need for Electrical Power – Craig (5 min)
Brief History of Wedge 1.0 – Don (10 min)
EMI Wedge 2.0 Efforts - Craig (10 min)
EMI Wedge 1.1 Efforts – Don (5min)
EMI Wedge 3.0 Efforts – Wil (10 min)
Potential Benefits of DO Involvement (10min)
Next Steps (10min)

3. Design Outreach (Greg)
Greg’s Story
Design Outreach
Lifepump
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.

4. Needs & Potential (Craig)
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.

5. History (Don) Invented by Don Sternitzke from Liberia Vision
Originally a Surf Model
River Model Adaptation
Wedge 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.

6. Wedge 2.0 (Craig)
EMI’s First(?) Ever Appropriate Technology Product Development Project
Don Contacted EMI 2010 as EMI exploring new programs
Wedge Intensive April 2011 –
Purpose: Design, Build & Test next-generation prototype
Approach: Similar to classic EMI Design Team approach

7. Wedge Intensive 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

8. Ultimate Goals (Design Criteria)
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

9. 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 –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.

10. 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: watts at 60 RPM (Glen Eyrie Camp Creek)

11. Hydrodynamic Modeling – Existing Wedge

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

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

14. Wedge 2.0 Fabrication
Sam Loomis built adjustable propeller in Seattle garage
Chris, Tim & Pat Fabricated Housing and tube in Colorado Springs
EMI Team (Andy, Justin, Wil, Craig) assembled Majik Pie Generator and electrical testing equipment at Chris’ garage

15. Wedge 2.0 Testing
Fall 2013 in COS Utilities Garden of Gods Wastewater Treatment outfall ‘creek’
Optimize Wedge 2.0; and Compare to 1.0

16. Wedge 2.0 Testing
See video

17. Wedge 2.0 Test Results
Wedge 2.0 generated 400% more power than Wedge 1.0
peak power output of the Wedge 2.0 was 126 watts. 
peak power of Wedge 1.0 was 28 watts (attempt to optimize pulleys)
Wedge 2.0 approx 200% more efficient
Efficiency calculation very sensitive to water speed & cross-sectional area.
peak Efficiency for the Wedge 2.0 occurred in trial 21 and was 79%. 
peak efficiency for Wedge 1.0 was in trial 26 and was 40%
Optimal Configuration of Wedge 2.0:
Blade angle of 10 degrees
Tube angle of 32 degrees

18. Wedge 1.1 Improvements (Don)
Variable Speed Drive
Other – see also Wedge 1.1 VSD ?

19. Wedge 3.0 Improvements (Wil)
“Suitcase” Model
Reuse 55 gal barrel drum – housing and split ‘catcher’
Car fan as turbine
Direct drive on angle through tube housing

21. 2 4 6 8 10 12 14 16 18 20 22 24

22. Next Steps Independent Development or “Merge” 1.1 and 2.0 and 3.0?
Short Term Test to Optimize Merge?
Long term test to prove reliability over time
Fine-tune for Developing World?
Field test in Developing World – Haiti?