Retrofitting hydro electricity to SA s water supply infrastructure

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1 Retrofitting hydro electricity to SA s water supply infrastructure B. Barta PrEng May 2013 Cell: bartab@iafrica.com

2 Hydropower amongst renewable energy technologies Hydropower is recognised world-wide as a robust and well-tested renewable energy technology in electricity generation Hydro development is preferred due to most efficient energy conversion processes Modern installations can convert up to 95% of moving water into electricity Hydro electricity is non-consumptive use of water and least quantities of carbon are produced during construction and generation

3 Hydropower world-wide 16% of total electricity production world-wide came from hydro plants in 2011 Annual growth rate world-wide has been almost constant at 3% over last fifty years Most recently developed hydropower in less developed countries are small scale run-of-river installations Developed countries are concentrating on hydro retrofit (augmentation) to existing primary water infrastructure (e.g. dams, canals, pipelines, etc.)

4 Categories of hydropower installations Low-head (pico, micro,mini and small hydropower) up to 10 MW typically run-of-river with or without a storage (turbine type: Banki, Francis or Kaplan) Medium-head between 10 MW and 200 MW depending commonly on the dam regulated storage (turbine type: Francis or Kaplan or modifications) High-head over 200 MW (turbine type: Pelton, Francis or modifications) specific type in this category would be pumped storage scheme

5 Selection of turbine type (specific speed versus head)

6 World hydropower in operation, under construction and planned capacity (2012) Hydropower in operation and under construction Planned hydropower

7 Large hydropower installed in Africa Africa s hydropower potential economically feasible: TWh/annum in operation: 7% development potential: 93%

8 Hydropower in Southern Africa south of Congo River Country Installed capacity (MW) Development potential available (MW) Angola Botswana Nil - DR-Congo Lesotho Malawi Mozambique Namibia South Africa Swaziland Tanzania Zambia Zimbabwe Total

9 Status of hydropower in South Africa (2010) Installed capacity: (i) operational 665 MW (ii) idle/defunct 11 MW Pumped storages: (i) operational MW (ii) new (Ingula) MW Overall hydro potential: MW for all types excluding pumped storages and imported hydropower

10 Pumped storage installation for peaking supply (Ingula 1332 MW) Bramhoek RCC lower dam 26 million m 3 Bedford CFR upper dam 22 million m 3

11 Where to look for new and/or dormant hydropower?

12 SA s most atractive hydropower development options) Refurbishing/upgrading of existing hydroelectric installations Retrofitting turbine/generator units to existing and newly build dams and water transfer schemes (WTS) Extracting hydro energy from gravity/pressure water supply/distribution systems Ocean hydropower through tidal/wave energy Importing hydropower from elsewhere in Africa

13 Quantitative opportunities in hydropower development Refurbishment/upgrading of existing plants in ownership of municipalities or DWA: 70 GWh/a Hydropower sets to existing (new) dams (300 dams in SA are suitable): 500 GWh/a Inter-basin Water Transfer Schemes (at gravity flow components): 300 GWh/a Municipal/water utility distribution systems - in line hydropower (for own use or supply to regional/ national grid): 250 to 500 GWh/a Greenfield hydropower sites (available more than 5000 MW around SA if storage regulated)

14 Locations of feasible small hydropower (300 kw to 3 MW) around South Africa Existing dams Water Transfer Schemes

15 BARRIERS/CHALLENGES in developing hydropower in SA Environment Impact Assessment (EIA) Water Use Permit as per National Water Act (No. 36 of 1998) - exclusive to hydropower State (public) ownership of vital resource/ infrastructure (access, servitudes, etc.) Power Purchase Agreement (PPA) National Energy Regulator SA license Funding constraints

16 On the regulated path in developing SA s hydropower Prior SA s IRP (May 2011) alternative/renewable energy technologies Kyoto Protocol adopted in 1997 and ratified in 2005 (SA early signatory) SA s White Paper on RE (2003) target of GWh/a from RE + other goals CDM market available to signatories of KP since 2005 (poorly utilised in SA) Electricity Regulation Act (Act 4 of 2006)

17 On the regulated path in developing SA s hydropower - continued RE Feed-in-tariff programme ( ) REBID to REIPPP procurement programme ( since August 2011) small hydropower (1 to 10 MW) allocation of 75 MW REIPPP first bidding round no small scale hydropower bids (11/ 2011) REIPPP second bidding round (03/2011) two small hydropower proposals approved (14,3 MW in total i.e. 20% of allocation)

18 REIPPP second bidding round (hydropower capacity ,3 MW) Neusberg Hydro-electric Project Stortmelk Hydro (Botterkloof Barrage downstream of LHWP outlet)

19 Development layout and components of a typical hydro-electric scheme Source of hydro-energy Generator of hydro-energy Civil/mechanical items Electrical/ electronic Transmission of hydro-energy Access to source Diversion tunnel/ canal/pipeline Dam/weir/barrage Impoundment Spillway Outlets/Intake Access to plant Headrace Plant housing Turbine Penstock Surge device Tailrace Generator Controls Security/safety Transformers Transmission/ Distribution

20 Retrofit (augmentation) of existing water supply infrastructure - advantages Existing water facility (e.g. dam, canal, gravity pipeline, water transfer, pumped storage, etc.) monetary costs and environmental impacts at the energy source already incurred shorter time frame in procurement of a new scheme Lesser technological and business risks Wider, better and optimised usage of precious water resource

21 Development layout and components for a hydro-electric retrofit Source of hydro-energy Generator of hydro-energy Civil/mechanical items Electrical/ electronic Transmission of hydro-energy Access to source Diversion tunnel/ canal/pipeline Dam/weir/barrage Impoundment Spillway Outlets/Intake Access to plant Headrace Plant housing Turbine Penstock Surge device Tailrace Generator Controls Security/safety Transformers Transmission/ Distribution Note: Retrofitting hydropower to existing infrastructure, requires planning, design, costing and procurement primarily of the items indicated in red. The costs of hydro-energy source are excluded from the costing analysis.

22 Example of SA s dilapidated water infrastructure suitable for hydro retrofit

23 Eastern Cape Mbashe Dam & Hydro (bird s view of silted dam reservoir)

24 Examples of dam augmentation for hydropower to be added Dam augmentation increasing storage capacity for hydropower Dam augmentation with hollow structure to be added

25 Example of hydro retrofit costing at Hartbeespoort Dam (5,7 MW Ph 1) Cost benefits: CAPEX (Phase 1): R 98-million (R 17,2- million/mw installed) Operating costs: R 1,72-million/annum Income: R 16-million/a Payback: 13 years Life-time Cost at NPV: R 0,52/kWh (break-even tariff)

26 The dams in SA are being build without the SHP addition!?!?! The dams which are being build at present in South Africa: Mhlabatshane Dam De Hoop Dam by DWA no hydropower Mhlabatshane Dam by Umgeni Water no hydropower Ludeke Dam by Mbizana LA no hydropower Spring Grove Dam by DWA no hydropower NB: Namibia to build Nekartal Dam for irrigation with 1 MW hydropower installation.

27 Examples of hydropower dormant in SA s Water Transfer Schemes Best-to-develop existing Inter-basin Water Transfer Schemes for hydroelectricity generation: Assegaai to Vaal WTS (23 MW) Breede to Berg WTS (5 MW) Buffalo to Vaal WTS (1,5 MW) Orange-Fish-Sundays (25 MW) Usutu to Vaal WTS (5 MW) Future transfer: Mooi to Umgeni (? MW)

28 ORANGE-FISH-SUNDAYS WTS most suitable for hydropower development

29 Urban water services systems developing small scale hydropower Bloemfontein Water (regional water utility) ethekwini Water and Sanitation Department Uitkijk and Brankop reservoirs totaling almost to 1 MW Sea Cow Lake, KwaMashu 2, Aloes, Phoenix 1&2, Umhlanga 2 totaling to about 750 kw Tshwane Water Supply Area Rand Water (foremost water utility in South Africa) Estimated capacity of 8 MW is envisaged among 10 suitable city s reservoirs Reservoirs: Brakfontein (1,8 MW), Hartebeesthoek (2,2 MW), Klipfontein (3,4 MW), Zoekfontein (5,6 MW)

30 GREENFIELD HYDROPOWER POTENTIAL IN SA There are several perennial river systems suitable for development of macro/small scale hydropower: Mzintlawa River Eastern Cape 66 MW Lower Mzimvubu Eastern Cape 450 MW Tsitsa River Eastern Cape 200 MW Tina River Eastern Cape 50 MW Lower Orange Northern Cape 20 MW + Thukela River KwaZulu Natal MW

31 Natural distribution of renewable energy resources in South Africa

32 Small pumped storage hydro (PSH) in combination with other renewables Determination of required capacity of a wind/solar PV plant to compensate power demand of a small PSH Operation programme for a small PSH based on the intermittency/daylight solar radiation patterns to provide for a full or partial pumping requirements of a small PSH

33 Concept of small PSS powered by wind and/or solar PV power Upper tank Lower tank Pumping power (kw): Pp = gr * Qp * Hp * eff Generating power (kw): Pg = gr * Qg * Hg * eff NB: The pumping power is to be about the same as the generating power

34 Small scale RE projects below 1 MW (issues and constraints) REIPPP projects below one MW are excluded from opportunities of development Is that fair? Commercial banks will not finance SSRE projects below one MW Where to go for suitable finance? The process of permit applications from DWA and NERSA still to long to enable potential hydro bidders to satisfy REIPPP offer assistance to DWA and NERSA Evaluate chances of possible concession or leasing of under-utilized water storages for hydropower generation Re-evaluate hydropower potential in the provinces of Eastern Cape and KwaZulu-Natal.

35 INTEGRATED RESOURCE PLAN ( ) INCLUDES HYDROPOWER When are we going to harness available hydropower? THANK YOU