Marco van Dijk Lecturer University of Pretoria South Africa

Transcription

1 Marco van Dijk Lecturer University of Pretoria South Africa

2 Layout: Energy generation from current water Description Status quo Research project Research aims Pilot plants Technical issues

3 Description: Pressure-hydropower energy generated from pressurised conduits

4 Description: Foot print (1 MW) Wind turbine Pressure-hydro

5 Description: Cost of generating 1 MW???? Wind turbine Pressure-hydro

6 Description: Environmental impact Wind turbine Pressure-hydro

7 Description: Availability Wind turbine Pressure-hydro

8 Description: Allocation (IRP) Wind turbine (1850 MW) Hydro (75 MW)

9 Description: Drivers for a municipality to consider pressure-hydropower : Rising energy costs Reduced revenues Financial incentives Public perception

10 Status quo: White Paper on Renewable Energy introduced to SA in November 2003 WP on RE set-out target of GWh per annum from biomass, wind, solar and small hydropower no specific allocations Renewable Energy Market Transformation Project (REMT) May 2004 RE economics South Africa becomes a signatory to the Kyoto Protocol in CDM mechanism

11 Status quo: South Africa as a whole emitting about 500 million tons of emissions annually SA s emissions reduction commitment: 34% in 2020 below projected emissions scenarios Final Policy Adjusted IRP 2010: New-build Tech. Mix of 3725 MW (August 2011) be operational by 2014/15

12 Status quo: Final Policy Adjusted IRP 2010: New-build Technology Mix (August 2011) (MW) Onshore wind Concentrated Solar Power 200 Solar PV solutions Biomass & Biogas 25 Landfill Gas 25 Small Scale Hydropower 75 Small Scale IPP Projects (<5 MW) 100

13 Status quo: Development of small hydro in SA since 2003: Operational hydros: Sol Plaatje & Merino (3 & 4 = 7 MW) At feasibility stage: some 80 MW by 2014 Realistic growth to 2030: MW

14 Status quo: R & D in world-wide hydropower: Small Hydro Power Market Analysis to 2020 Pico (<20kW), micro (<100kW), mini (<1MW) and small hydro (<10MW) at perennial rivers, irrigation canals and water supply/distribution systems (significant potential) Adding hydropower to existing dams and bulk gravity/pressurised conduits (most sizeable in RSA) Pumped storages to pair with existing dams (pumping energy from other renewables as solar and wind) Marine/ocean hydropower from wave/tidal potential (in RSA researched at CSIR in Stellenbosch) Source: International Hydropower Association (IHA)

15 Status quo: How small can we go:

16 Project: Energy generation from current water Title: Energy generation from distribution systems Period: 2 years Funding: Water Research Commission with a number of collaborating organisations

17 Aims: Energy generation from current water To prove feasibility and technically possible Development of guidelines to identify potential hydropower locations Development of an assessment model including a cost benefit tool Development of optimization tool Demonstration using full scale pilot plants To illustrate benefits and complications Provide educational material

18 Pilot plants: A number of pilot plants by collaborating organisations are envisaged demonstrating the application of the technology City of Tshwane Metropolitan Municipality Queenswood Reservoir (PaT) Pierre van Ryneveld Reservoir Ethekwini Municipality Sea Cow Lake, Kwa Mashu 2, Aloes, Phoenix 1, Phoenix 2 and Umhlanga 2 Reservoirs Bloem Water Uitkijk and Brandkop reservoirs

19 Pilot plants:

20 Pilot plants: Crossflow turbine (BWG Hydropower) 16 kw used on site

21 Pilot plants:

22 Pilot plants: De Hoek reservoir Uitkijk reservoir 105.7km 1 170mm Ø Pre stressed Concrete De Hoek Res 22.7 Ml Uitkijk Res 9.1 Ml Brandkop Res 136 Ml Elevation (m) Brandkop reservoir Uitkijk - Brandkop profile De Hoek - Uitkijk profile HGL maximum flow Chainage (m)

23 Pilot plants:

24 Pilot plants:

25 Pilot plants:

26 Pilot plants:

27 Pilot plants: De Hoek reservoir Hmax = 75.5 m Qmax = 1.59 m³/s Elevation (m) Uitkijk reservoir Longitudinal profile HGL static conditions HGL maximum flow Chainage (m)

28 Pilot plants: Q40 = 0.64 m 3 /s: H = 66.1 m Q70 = 1.11 m 3 /s: H = 46.8 m Q100 = 1.59 m 3 /s: H = 16.8 m

29 Pilot plants: Uitkijk reservoir Hmax = 83.2 m Qmax = 1.42 m³/s Elevation (m) Brandkop reservoir Longitudinal profile HGL static conditions HGL maximum flow Chainage (m)

30 Pilot plants: Q40 = 0.57 m 3 /s: H = 66.3 m Q70 = 1.00 m 3 /s: H = 47.1 m Q100 = 1.42 m 3 /s: H = 17.5 m

31 Pilot plants: Example: Details of installation of cross flow turbines at Uitkijk and Brandkop Reservoirs Site Uitkijk Brandkop Units Flow rate Ml/day Base flow rate (70%) m³/s Velocity m/s Friction and secondary losses m Total head m Available head (varies) m Efficiency?? % Generated power kw Tariff?? R/kwh Annual energy value ±R ±R Estimated capital cost ±R1.5M R2.0M ±R1.5 R2.0M

32 Technical: Energy generation from current water A few technical issues to be borne in mind: i.the service reservoir operates as a tailrace ii.reservoir water inflows = outflows (use pattern and seasonal variation) iii.head fluctuation within service reservoir and the system head losses dictate the operating head of the turbine installation. iv.the base demand determines likely flow available to the turbine installation v.potential transient pressures should be analysed vi.still requires alternative dissipating system

33 Technical: A few technical issues to be borne in mind: vii.operational optimization of series connected systems viii.reliability of supply should not be compromised ix.further upgrading Energy generation from current water

34 For any additional information, please do not hesitate to contact us. Marco van Dijk: Bo Barta: Fanie van Vuuren: Free Water Research Commission report: Van Vuuren, S.J A high level scoping investigation into the potential of energy saving and production/ generation in the supply of water through pressurized conduits. WRC Report No. KV 238/10. THANK YOU