Transcript Slide 1
Understanding the current system supply constraints Corporate Affairs Division 21 February 2013 Disclaimer This presentation is used to aid communications with our employees and stakeholders. Certain statements in this presentation regarding Eskom’s business operations may constitute “forward looking statements”. All statements other than statements of historical fact included in this presentation, including, without limitation, those regarding the financial position, business strategy, management plans and objectives for future operations of Eskom are forward looking statements. Forward-looking statements are not intended to be a guarantee of future results, but instead constitute Eskom’s current expectations based on reasonable assumptions. Actual results could differ materially from those projected in any forward-looking statements due to risks, uncertainties and other factors. Eskom neither intends to nor assumes any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. In preparation of this document certain publicly available data was used. While the sources used are generally regarded as reliable the content has not been verified. Eskom does not accept any responsibility for using any such information. 2015/07/20 2 Overview • Our national electricity system is currently operating under constrained conditions and is in RED alert • The power system is extremely tight at present, particularly during the evening peak hours between 17h00 to 21h00 • We appeal to all employees and customers to reduce their electricity usage and to switch off all non-essential appliances over the peak period • No load shedding since April 2008, and we remain committed to keep the lights on 2015/07/20 3 Overview • Our national electricity system is currently operating under constrained conditions and is in RED alert • The power system is extremely tight at present, particularly during the evening peak hours between 17h00 to 21h00 • We appeal to all employees and customers to reduce their electricity usage and to switch off all non-essential appliances over the peak period • No load shedding since April 2008, and we remain committed to keep the lights on 2015/07/20 4 Why is there a serious constraint? • A large number of units are not generating to full capacity as a result of various problems on mills, draught groups, turbines, poor quality coal and vacuum problems • Koeberg unit 1 tripped on 20th February. Only the electrical supply side of the plant is affected and there was no impact on nuclear safety. Koeberg expected to be back on full load next week • Reduction in availability of Cahora Bassa from 1500 MW down to 650 MW due to flood damage on one of the lines • Additional 650 MW expected to return at the end of March, 200 MW by the third quarter of this year. 5 Boiler Tubes Boiler Tubes arranged to obtain maximum heat transfer 25 – 30 stories high Note the scale to a human 6 Boiler tubes Soot blower erosion Boiler superheater tubes buckle due to blockage and subsequent overheating Fly ash erosion damage (poor quality coal) • Did you know? Our 600 MW coal fired Boilers are more than 30 stories high with over 600 kilometres of tubing arranged around and inside the boiler • Did you know? It takes 8 to 12 hours for a boiler to cool down before inspections and repairs can begin as the temperature inside a boiler can reach up to 1400 degrees Celsius 7 Turbines Steam, produced in the boiler, turns the turbines at 3000 rpm. A turbine consists of various stages, high, intermediate and low pressure. These are connected to the shaft of the rotor, a magnet. The rotor spinning inside the stator converting the energy from the steam into electricity. Magnet • Did you know? A low pressure turbine can have as many as 12 stages, rows of blades, each weighing in at approximately ±30 kg. Stator 8 Actual plant unavailability • Full and partial load losses have increased substantially since the beginning of February • As a result the planned maintenance has had to decrease • This puts pressure on units requiring urgent maintenance increasing the probability of failure 9 Usage of Emergency reserves 2013 Usage of OCGT’s increased due to plant unavailability, compare to previous years The high number of frequency incidents below 49.7 Hz is an indication of the system being run tighter. 10 Approximate outlook for next 4 months • The prediction below shows possible scenarios under various unplanned outage conditions. • These scenarios change regularly depending on the load forecast, planned maintenance and forced outages 4500 MW Unplanned Week 25-Feb-13 04-Mar-13 11-Mar-13 18-Mar-13 25-Mar-13 01-Apr-13 08-Apr-13 15-Apr-13 22-Apr-13 29-Apr-13 06-May-13 13-May-13 20-May-13 27-May-13 03-Jun-13 10-Jun-13 17-Jun-13 24-Jun-13 Demand Forecast 31162 31309 31320 31255 31263 31741 32365 32810 33258 33304 33723 34494 34970 35454 35779 36030 35879 36220 Maintenance 5803 5980 5733 6298 6643 5077 4314 4223 3868 4246 3078 2738 2605 2455 2640 1867 1292 1406 No Additional Levers, 1300 MW OCGTs No Additional Levers, 0 MW OCGTs 5500 MW Unplanned No Additional Levers, 1300 MW OCGTs No Additional Levers, 0 MW OCGTs 6500 MW Unplanned No Additional Levers, 1300 MW OCGTs No Additional Levers, 0 MW OCGTs 11 Actions taken to date • Emergency Response Command Centre Activated and meet daily to review the system • Emergency generation utilised: • Open Cycle Gas turbines are run over peak periods • Hydro stations such as Gariep and Vanderkloof are also operated • Industrial customers are being paid to reduce demand through the Power Buy Back programme. Approximately 1000 MW of load has been reduced. • Demand Market Participation Up to 290 MW of load can be reduced over peak periods through the Demand Market Participation (DMP) program • Non-firm cross boarder contracts are reduced when the network is constrained • Communication to electricity consumers to reduce load between 5pm to 9pm 12 What can you do to assist • Reduce consumption of electricity from 5pm to 9pm and encourage family and friends to do the same • Participate in energy savings through the 49m campaign Eskom will be rolling out a Residential Mass Roll Out campaign shortly 13 Conclusion • Eskom remains committed to keeping the lights on • We need all electricity consumers to switch of all electrical appliances that they do not absolutely require from 5pm to 9pm • The electricity system has been tight for several years now and we have developed contingency plans for dealing with it, especially during particularly tight periods 14 Insert image here Thank you Websites and email contacts Eskom website: www.eskom.co.za Eskom email: [email protected]