1. Lilongeni Kayofa Supervisor: Theuns D.van Schalkwyk Co-supervisor: Robert Dobson Topic: Feasibility study and business plan for manufacturing a 3 kw-electrical solar Stirling engine and dish, for a stand- alone power supply unit Industrial Engineering Department, Stellenbosch University Energy Postgraduate Conference 2013

2. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS Energy situation in Africa Africa has some of the best solar regions to harness solar energy Solar energy remain largely untapped in some regions A high number of people have no access to electricity (see Table 1)  Rural areas are particularly affected  Majority of this people live in off-grid areas  Grid extension is expensive and will take year in certain areas  North Africa has a reached a 99.4 % electrification rate using solar energy Possible solution that Africa can explore: A solar Stirling dish system Table 1: Africa’s Electricity Access in 2010 (Source: IEA) RegionPopulation without electricity millions Electrification rate % Urban electrification rate % Rural electrification rate % Sub-Saharan Africa 58931.864.212.9 North Africa199.410098.7 Africa59042.972.123.6

3. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS Solar source of Africa A Stirling dish is economical in regions that receives a DNI > 1,700 kWh/m²/year ( Stine and Geyer ) Therefore, Africa has a potential in most of the regions ( see figure below)

4. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS What is a Stirling dish system ? Concentrated Solar Power (CSP) technology Converts solar energy → heat energy absorbed by the receiver → mechanical energy by Stirling engines → electric energy by generator Main components: Concentrator, receiver/ Stirling engine, tracking system,generator,storage (optional)

5. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS Why the Stirling dish? Most efficient solar energy technology around – 31.25 % efficient Modular : scalable power size –Currently from 3 -30 kW per unit Stand-alone Low maintenance and operation costs Easy to operate Favourable for remote areas: left unattended No supporting infrastructure required Can be used for all types of terrain Can be hybridised No water usage required except to clean to mirrors Electrical storage : batteries Disadvantages High start-up costs No thermal storage

6. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS Purpose of study Problem Potential exists Business people are sceptical in investing Risks are unknown No local (African ) manufacturer exists Purpose Determine whether there is a viable market in Africa for the use of a Stirling dish

7. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS Research design Literature studies Questionnaires –Survey ( Likert Scale questionnaire) : communities without access to electricity –Second questionnaire: to verify and validate whether the produced business plan is satisfactory

8. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS Survey output Socio-economic Various households use at least five different sources of energy to generate energy Heat Lighting Main reasons why they have no electricity in their houses The monthly quantity and costs of the energy sources The average total monthly income per household is N$ 3800.00 Majority of the households are headed by pensioners 53 % of households have more than 7 occupants Type of housing structures Interest and perception on Stirling dish Participants are highly interested in the Stirling dish 10 % of the households were will take out loan of > N$ 10 000.00 Areas prone to theft and vandalism Households interested in using the Stirling dish the whole day N$ 1.00 ≈ R 1.00

9. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS Manufacturing plan Decide on: Production time Process to use Machines and tools Factory set-up Workforce Location of factory Builds Stirling engines and dishes in the most cost-effective manner Competitive with conventional Preferably using local materials and labourer as much as possible

10. SAHPA ® South African Heat Pipe Association Energy Postgraduate Conference EPC2013, 11-14 Aug 2013 iThemba LABS Research expectations Questionnaire results Manufacturing layout Logistic of factory Economic results Business plan

11. Print master Lilongeni Kayofa Supervisor: Theuns D.van Schalkwyk Co-supervisor: Robert Dobson Topic: Feasibility study and business plan for manufacturing a 3 kw-electrical solar Stirling engine and dish, for a stand-alone power supply unit Energy situation in Africa Africa has some of the best solar regions to harness solar energy Solar energy remain largely untapped in some regions A high number of people have no access to electricity (see Table 1)  Rural areas are particularly affected  Majority of this people live in off-grid areas  Grid extension is expensive and will take year in certain areas  North Africa has a reached a 99.4 % electrification rate using solar energy Possible solution that Africa can explore: A solar Stirling dish system

12. RegionPopulation without electricity millions Electrification rate % Urban electrification rate % Rural electrification rate % Sub-Saharan Africa 58931.864.212.9 North Africa199.410098.7 Africa59042.972.123.6 A Stirling dish is economical in regions that receives a DNI > 1,700 kWh/m²/year ( Stine and Geyer ) Africa has a potential in most of the regions (see figure below) Table 1: Africa’s Electricity Access in 2010 (Source: IEA)

13. What is a Stirling dish system ? Converts solar energy → heat energy absorbed by the receiver → mechanical energy by Stirling engines → electric energy by generator Main components: Concentrator, receiver, tracking system and Stirling engine, generator,storage (optional) Why the Stirling dish? Most efficient solar energy technology around – 31.25 % efficient Modular : scalable power size –Currently from 3 -30 kW per unit Stand-alone Low maintenance and operation costs Easy to operate

14. Favourable for remote areas: left unattended No supporting infrastructure required Can be used for all types of terrain Can be hybridised No water usage required except to clean to mirrors Electrical storage : batteries Disadvantages High start-up costs No thermal storage Purpose of study Problem Potential exists Business people are sceptical in investing Risks are unknown No local (African ) manufacturer exists Purpose Determine whether there is a viable market in Africa for the use of a Stirling dish

15. Research design Literature studies Questionnaires –Survey ( Likert Scale questionnaire) : communities without access to electricity –Second questionnaire: to verify and validate whether the produced business plan is satisfactory Survey output Socio-economic Various households use at least five different sources of energy to generate energy Heat Lighting Main reasons why they have no electricity in their houses The monthly quantity and costs of the energy sources The average total monthly income per household is N$ 3800.00 Majority of the households are headed by pensioners 53 % of households have more than 7 occupants Type of housing structures

16. Interest and perception on Stirling dish Participants are highly interested in the Stirling dish 10 % of the households were will take out loan of > N$ 10 000.00 Areas prone to theft and vandalism Households interested in using the Stirling dish the whole day N$ 1.00 ≈ R 1.00 Manufacturing plan Decide on: Production time Process to use Machines and tools Factory set-up Workforce Location of factory Builds Stirling engines and dishes in the most cost-effective manner Competitive with conventional Preferably using local materials and labourer as much as possible

17. Research expectations Questionnaire results Manufacturing layout Logistic of factory Economic results Business plan