Prof Wikus van Niekerk Director of CRSES Prof Frank Dinter Eskom Chair in CSP Stellenbosch University

Prof Wikus van Niekerk Director of CRSES Prof Frank Dinter Eskom Chair in CSP Stellenbosch University

Fact not fiction: The true potential of concentrating solar thermal power 19/05/14 Prof JL (Wikus) van Niekerk Prof Frank Dinter Director of CRSES Eskom Chair in CSP 14 May 2014 2

Outline Solar resource and potential for CSP in SA CSP Technologies Advantages of CSP with storage system Current CSP projects in South Africa

Utilising the potential of the sun as source of energy I 4 The sun is the world s largest source of energy The part of the earth directed to the sun is permanently exposed to a radiant power of 1.73*10 11 MW which is equal to the capacity of 173 million big coal power plants Each year the sun sends over 1 billion TWh of energy to the earth which is equal to 60,000 times the world s electricity needs From a mathematical perspective, less than 3% of the surface area of the Sahara would be sufficient to meet the world s energy demand with solar power plants Unfortunately the utilisation of solar energy is not that easy due to the low power density Area required to supply the world, the EU-25 or MENA with solar power from the Sahara. Source: Münchener Rück

Utilising the potential of the sun as source of energy II The ESTELA CSP world forecast 5

6 South Africa Direct Normal Irradiance DNI: Direct Normal Irradiance used for CSP resource assessments Spain USA South Africa

What could be possible with CSP in SA? 7

8 What is CSP? Makes use of mirrors to concentrate the sun s rays on receivers that absorb the heat and then use it for process heat or electricity generation, hence concentrating solar power, or CSP

Storage Boiler 9 CSP plant layout Grid interface Steam turbine Generator Parabolic trough collector Condenser Dry/wet cooling

Parabolic trough from the 80 s (still operating) 10 Solar Energy Generating Systems, SEGS, California (Source: SANDIA)

World s biggest trough plant with TES Solana (Abengoa) now in operation 280 MWe, 6 hours storage (molten salt), Solar field 2.2 km 2, Area 1 200 ha, Annual energy production of 980 GWh. 11

12 First CSP plant to demonstrate baseload Gemasolar in Spain 20MWe, 120MWth 15 hours storage 24h per day full load in its first summer Latest: 24h per day almost all year (year 3)

13 Gemasolar key facts Item Country, Region Land area Solar resource Electricity Generation Cost Value Spain, Seville Andalucía 195 Ha 2,172 kwh/m 2 /yr (like Stellenbosch) 110 GWh/yr (planned) 230 million Euro Heliostat aperture area 304,750 m 2 Number of heliostats 2,650 Heliostat size 120 m 2 Tower height 140 m Heat transfer fluid Molten salt Receiver outlet / inlet temperature 565 C / 290 C Turbine capacity (gross) Storage Source: NREL/SolarPACES CSP database 19.9 MWe 2 tank, 15 hours

14 World s largest Solar Tower plants Ivanpah Solar Power >Owners: NRG Energy, Google and BrightSource >Location: Mojave Desert in California, USA >Technologie: Solar power tower, direct steam generation >Power: 3 x 130 MW > Commission date: 2013 Source: Ivanpah

More than 2.3 GW of STE plants in operation in Spain Most of them with storage systems to produce electricity also in the evening peak hours Storage medium is a molten salt mixture (60/40) of sodium nitrate (NaNO 3 ) and potassium nitrate (KNO 3 ) 15 Source: Protermosolar

Advantages of CSP with thermal energy storage 16 The main advantage of CSP technology against other RES as PV or wind power is the capability to provide dispatchable power by storing solar energy through thermal energy storage Flexible and predictable electricity generation on demand Source: DLR

Advantages of CSP with thermal energy storage 17 Flexible and predictable electricity generation Avoidance of production interruptions resulting from the intermittency of solar radiation Generation of solar power decoupled from weather conditions and time Shifting of power generation to periods of highest demand 24 h/d continuous production capability Regulation and frequency response Support for power quality Contribution to system flexibility supporting the integration of other RE sources

Power [MW] Hot Salt tank Level [%] Solar Radiation [w/m2] Continuous generation 24 h/d 18 11.09.2012 18.09.2012 100 90 80 1200 1000 70 60 800 50 600 40 30 400 20 10 200 0 0 HOT SALT TANK LEVEL(%) POWER S5 (MW) DNI (W/m2) Source of data : Real measured values at Andasol 3, Spain

Power [MW] Hot Salt tank Level [%] Solar Radiation [w/m2] 19 Continuous generation 24 h/d 17.09.2012 80 1200 70 1000 60 50 800 40 600 30 20 10 400 200 0 0 HOT SALT TANK LEVEL(%) POWER S5 (MW) DNI (W/m2) Source: Real measured values at Andasol 3, Spain

Power situation in South Africa 20

21 CSP Value Proposition and Cost of CSP in SA Only renewable energy technology with a proven, affordable, large-scale energy storage solution (except of course hydro pump storage) LCOE already less than half that of peaking OCGT plants in South Africa Renewable energy technology with the largest potential to establish a significant manufacturing industry, also for the export market RE IPP PP has recognised the value of storage that CSP plant can offer and hence in Round 3 (and 3b) allowed 2.7 times the tariff in the evening, 5-10pm R 3.94/kWh

22 Khi Solar One First CSP power plants in SA I >Owners: Abengoa solar and IDC >Location: Upington, South Africa >Technologie: Solar power tower >Power: 50 MW >Commissioning date: 2014 Source: Abengoa Solar 22

23 First CSP power plants in SA II Kaxu Solar One >Owners: Abengoa solar and IDC >Location: Pofadder, South Africa >Technologie: Parabolic trough >Power: 100 MW >Commission date: 2014 Source: Abengoa Solar

24 First CSP power plants in SA III The Bokpoort CSP Project >Owners: ACWA Power & Solafrica >Location: Groblershoop, Northern Cape, SA >Technologie: Parabolic Trough 9 hr storage >Power: 50 MW

Symphony of Renewables 25

26 Conclusions CSP is already, or will in the near future, be cost competitive with mid-merit or peaking power plants in South Africa By taking all the fuel costs into account over the lifetime of a coal fired plant, CSP is already competitive in SA CSP, with storage, is an ideal fit for SA s demand curve with a peak in the early evening Solar electricity, PV and CSP, complement each other in areas of high solar irradiance Potential to localise the manufacture of CSP components is much greater than for many other technologies (especially nuclear), but it will need a guaranteed future market in SA of sufficient size

27 Acknowledgements Industry associations: SAPVIA SASTELA Reports by: Abengoa NREL Frost & Sullivan Black & Veatch Department of Energy & National Treasury

Contact Details 28 wikus@sun.ac.za frankdinter@sun.ac.za www.crses.sun.ac.za concentrating.sun.ac.za