A least-cost electrification proposal for Kisiizi, Uganda Sten Bergman Sr. Energy Specialist, The World Bank

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1 A least-cost electrification proposal for Kisiizi, Uganda Sten Bergman Sr. Energy Specialist, The World Bank 1. Introduction Kisiizi Hospital is a Church of Uganda "Private not-for-profit health care provider rurally situated in the mountains of North Kigezi in Rukungiri district in the South West of Uganda. The hospital was founded in 1958 and has since then grown significantly. The hospital owns and operates a small micro-hydro plant of approximately 60 kw size. However, due to an increasing demand for electricity (approximately 125 kw) the hospital has investigated the opportunity to expand the hydro-plant to a maximum of 250 kw. Given excess capacity the hospital could be a private distributor to nearby community for a number of years, until the main grid reaches Kisiizi. The nearest UEB main grid is in Rubaare, 29 km away. Kisiizi Hospital area, Rukungiri District 2. A proposal of a low-cost design with a sequenced approach There a few suggestion on how to increase power supply in Kisiizi. ESKOM recommended to connect Kisiizi with the Main grid in Rubaare with a three-phase steel wire design for an approximate cost of USh 310 million (USD 220,000). Another option suggested is to connect by a Single-phase line to Rubaare, though limiting the power transfer to approximately 200 kw. Costs should amount to USD 80,000. In both cases LV networks are needed and cost estimated to around USD 50,000. Assuming 600 customer and connection costs of USD 100 per customer the cost per connection in these 1

The hospital was founded in 1958 and has since then grown significantly. The hospital owns and operates a small micro-hydro plant of approximately 60 kw size.

2 proposed concepts comes to 508 USD/connect and 308 USD/connect. However the latter is power limited and will not make a sustainable contribution to power needs. Another proposal, which is recommended here is to develop the micro-hydro to the need of the hospital, around 217 kw (Option 1 and electrify only the closest surroundings, leaving the distant areas to a following main-grid connection, maybe a few years ahead, as the main grid option is viable. To ensure the most number of customer connected the barrier of high up-front cost should be eliminated. The system design should therefore include all design elements and customer parts in its conceptual framework as well as significantly lower the connection fee for any user. Kisiizi, trading center and shops along the main route to Rubaare In order to reduce operating costs as much as possible it is suggested that "pre-pay" meters, (USD 65) with current limiting functions are applied as standard. The proposed scheme combines the electrification of the hospital area with a cable network with LV overhead lines to nearby trading center, town and market area. In total a network with a power delivery within maximum 900 m from the generator location. This proposal results in a LV system of higher cost than UMACIS (USD 34,000 compared to USD 15,000) but it reinforces the distribution and most likely reduces operating costs, need for maintenance etc. However reducing the initial need for a costly MV system of approximately USD 145,000, this system seems more appealing from a commercial perspective and it is not "sunken cost" as the system will be operable when main grid is connected (single-phase or three-phase) Based on the evaluation (See Annex) a proposal for Kisiizi hospital is to: 2

to a following main-grid connection, maybe a few years ahead, as the main grid option is viable. To ensure the most number of customer connected the barrier of high up-front cost should be eliminated.

3 (i) Initially develop the Kisiizi hydro-power plant to a 217 kw system (Option 1), connect through a local LV only mini-grid the commercial enterprises in nearby Kisiizi town and trading center, estimated to accommodate around a maximum 450 households and 150 commercial users. Include service-connection and meters in the customer package. Customers connection fees should be in the range USh 10,000-20,000, in order to get as many customers as possible from the start. Load management (e.g. timer control) should be applied to at least water heaters (17 kw) and other shiftable commercial loads in order to reduce peak power limitation. (ii) When the load growth has expanded the electricity consumption to more than 217 kw extending the main grid from Rubaare, 29 km from Kisiizi, with a 19,7 kv single phase steel connection, connecting approx. another 500 and 50 commercial customers on the route, and switching some of the loads in Kisiizi to the main-grid (Cost USD 100,000 including transformers) (iii) When load growths along the line and capacity restrictions are met another 19,7 kv Single phase spur could be connected and customer reconnected accordingly. Last part of the line could result in a two-phase line allowing for change to 33 kv transformers if needs are there. (iv) As load growth continues the last step imply a complete three phase upgrading of the main-grid extension to a full three-phase main-grid connection. At this point the hydro-power plant in Kisiizi will be connected at the end of this line to maingrid for generating bulk-supply to the main-grid and as a back-up for the Kisiizi hospital. Building a LV network only in Kisiizi and using the upgraded hydro-power generator will most likely due for at least five years perhaps more if a load management system is applied. Solar water heaters could e.g. be applied to reduce some energy consuming loads at this time to further defer investments another year. The proposed network design as shown in Fig. 1 comprise of a combined cable network for electrifying the hospital premises and a LV single phase network for extending to nearby trading center, town and market. The three phase cable network is terminated in a central small sub-station from where the overhead lines are distributed. Also one overhead spur is extend from a cable box termination. 3. Cost estimation Approximate cost for this concept is: Cable network (1000 m 4 core 70 mm 2 ) 19,000 LV network (5000 m 25 mm 2 single-phase) 15,000 Customer connection (poles, drop wire, service wire, ready board, pre-payment meter with current-limiting function, 560 a USD 100) 56,000 Pre-payment meter central system 10,000 Substation, cable boxes and protection 10,000 3

Customers connection fees should be in the range USh 10,000-20,000, in order to get as many customers as possible from the start. Load management (e.g. timer control) should be applied to at least water heaters (17 kw) and other shiftable commercial loads in order to reduce peak power limitation.

4 Design and Construction (10 persons 3 weeks) 5,000 VAT (17%) 20,000 Transport 5,000 Total 140,000 Fig 1. Conceptual layout of Kisiizi LV system 4. Total investment cost for Kisiizi: Investment Hydro Power (217 kw) 317,000 LV network 140,000 Total 457,000 Number of connections Households 450 Commercial 150 Hospital -all load taken care of 4

Total investment cost for Kisiizi: Investment Hydro Power (217 kw) 317,000 LV network

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6 ANNEX: Evaluation of UMA and ESKOM electrification proposals UMA Consultancy & Information Service (UMACIS) developed a conceptual electrification design proposal together with a business plan in May The first proposal was evaluated and commented by ESKOM consultants in September The UMACIS proposal resulted in proposing a combined network of 11 kv three phase MV network (440 m) 11 kv Single-phase network (11,400 m) and a LV network of 5,600 m estimated to a total cost of approx. USD 200,000 including the construction costs for 10 people working 3 weeks as well as VAT of 17% on material (USD 28,000). All lines using 50 mm 2 SCA conductors. The peak-power demand in Kisiizi is estimated by UMACIS at 182 kw; 68 kw for Kisiizi hospital, 61 kw for Kisiizi Town, 10 kw for the market area and 43 kw for the Kihanga area. Customers are expected to guarantee USh 100,000 (USD 60) as a "connection fee" Expectations are therefore high on tariffs similar to UEB tariffs. The total number of estimated connections were 616 resulting in a total cost per connection of USD 408. ESKOM evaluated the UMACIS proposal and recommended some changes. E.g. reducing LV conductor sizing to 25 mm 2 and connecting Kisiizi to the main grid in Rubaare via a steel wire three-phase connection at a total cost of USh 10 million/km. The system cost in this case was estimated to USD 305,000. The number of connections were the same so cost per connection in ESKOM's recommendation was therefore USD 508 but could be as low as 322 if another 500 customer were connected en route. A comparison between UMACIS, ESKOMs, A possible SWER main grid connection and this proposal (at a customer basis of about ) is shown in table1. Table 1. Comparison of costs for Kisiizi designs Design Approach UMACIS ESKOM SWER This proposal MV+LV 3-phase steel Main grid Cost for MV 140, ,000 80,000 0 Cost for LV 45,000 45,000 45,000 80,000 Service drop, poles, 60,000 60,000 60,000 60,000 ready-boards, meter etc. (600 customer) Total cost 245, , , ,000 Comments Area expansion possible 500+ more customer Power limited to Limited distribution Cost per connection USD potential 200 kw area

The UMACIS proposal resulted in proposing a combined network of 11 kv three phase MV network (440 m) 11 kv Single-phase network (11,400 m) and a LV network of 5,600 m estimated to a total cost of

3.0 Results and Discussions

3.0 Results and Discussions Estimating the cost of electrification technology options to aid electricity access scale up: The case of Ghana F. Kemausuor * 1, I. Adu-Poku 1, E. Adkins 2, A. Brew-Hammond 1 1.0 Introduction 1 The Energy