A Feasibility Study on the Implementation of a Micro-Hydro Scheme in Sioma, Zambia

Hans Petter Bjørnåvold (0602641)

3rd Year Manufacturing & Mechanical Engineering School of Engineering, University of Warwick

Introduction

• Visited Zambia and Sioma in 2005 • Witnessed the problems the community faces • Rural infrastructure development is imperative

• Fire fighting problems will not lead to progress

The Sioma Falls

Project Specification

• Research and prove viability of hydroelectric scheme in Sioma, Zambia

• Produce a proposal for such a scheme • Including initial technical analysis

• Apply for support from local government • Network with charities • Put plan into action

• Outside academic boundaries

Micro-Hydropower

• Small scale harnessing of falling water • Typically generates less than 100 kW

• Benefits from same advantages as larger scale hydropower: • No fuel burnt causing minimal pollution • Low operation and maintenance costs • Reliable and historically proven technology • Water is free and completely renewable through continued

rainfall • 1.5 billion people in developing countries do not have

access to electricity • Micro-Hydro provides a realistic alternative for decentralized

energy generation

Micro-Hydropower

Typical Micro-Hydro layout – “Run of the River“ scheme Source: http://www.itdg.org/?id=micro_hydro_faq, retrieved 19 April 2009

Location: Sioma, Zambia

• Location: Barotseland, South Western Zambia (approx. 315 km from Livingstone)

• Population: 1000-1500 • Accessibility: 4-5 hours in 4x4 (bad road conditions) • ZESCO unwilling to build sub-station to power community • Proximity to Zambezi River makes micro-hydropower ideal

Image Source: maps.google.com, retrieved 24 April 2009

Sioma

Location: Proposed Site

Sioma Falls (Zambezi River) Head: 10-15 metres

6 km 4 km Sioma Village Sioma Falls Woodworking

Workshop

Source: http://www.toucan-reisen.de/cms/front_content.php?idart=235, retrieved 20 April 2009

Power Requirements

Village: 24,830 W Woodworking Workshop: 20,000 W

Load Factor = [Average Power] / [Peak Power] • Average Power = 20.2083 kW • Peak Power = 35 kW • Load Factor = 56.92%

Turbine

• L-1 Turbine • Manufactured on site through local labour • High Efficiency at low head sites • Easy operation and low maintenance • Scalable to suit different situations using an adjustable distribution

Variants of L-1 Turbine Source: McMULLEN, C., Low Head Micro Hydro in Developing Countries: The L-1 Turbine,

April 2004, 3rd Year Project, University of Warwick

L-1 Turbine Casing and Propeller Source: LI, S. C., Giving the lowdown on small hydro, International Water

Power and Dam Construction, November 2000

Initial Design Proposition

– Based on estimates

Intake/Canal • Parallel to river flow • Rock/logs for water diversion • To generate 46.1 kW from 10 m head we need:

• 0.587 m3/s flow

Forebay Tank • Primarily used as settling basin • Incorporates:

• Spillway • Trashrack • Cover

• Integration of water taps

• Decreases risks of collecting water • Reduces distance to safe water

Penstock • Typically 1/3 of costs • Material: HDPE • Diameter: +/- 600 mm • Minimum wall thickness: 16.2 mm • Critical shut off time: 0.59 s

• Thermal Expansion absorbed in bends • Supported by 2 m3 anchor blocks every 20 metres • Control measures:

• Gate valve

Potential Contribution

• Local Clinic • Replace diesel generator • Increased comfort – attract permanent doctor

• Elementary and Secondary School • Lighting will allow night classes

• Woodworking Workshop • Replace diesel generator • Allows for economically competitive production

• Local Businesses and Villagers • New opportunities (e.g. Mobile phone charging, sewing workshop etc.)

• Integration with irrigation and water supply projects • Use of mechanical power to power pump – use existing canals

Financial Viability

• Total cost approx. £45,000 • Return on investment not realistic

• Rely on charity sponsorship for start up costs

• Maintenance cost of £50 per kW

• Annual cost: £2,305 • Funded through woodworking workshop tariff fees

– £9 per day or £0.05 per kWh

Conclusions

• Power Requirement: 45.83 kW • Turbine: L-1 • Penstock: estimated 51 metres HDPE, 600 mm diameter • Cost: £45,000 + annual maintenance fees (£50 per kW)

• Implementation of a micro-hydro scheme is viable

• In comparison with diesel generator it is far more sustainable • Would provide an opportunity for development and improvement to quality of

life

What happens next?

• Technical visit over the summer • June or September • Aim is to develop project to the next phase

• Source equipment suppliers • Complete arrangements with local government • Apply for bursaries/fundraise • Commence construction July 2010

Thank you for listening