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HomeMy WebLinkAboutTerror Lake Unit 3 Hydroelectric Project Thermodynamic Efficiency Measurements - Feb 2014 - REF Grant 7040013KEA Terror Lake Power plant Thermodynamic Efficiency Measurements, Unit 3 Measurement date: 1 - 2 February 2014 Draft report 2014-03-03 Assignment no.: 5132673 Assignment no. 5132673 Document no.o502 Revision:01 Terror Lake Unit 3 report.docx 03.03. 2014|Page 2 of 24 Summary Norconsult AS was engaged by KEA to perform measurement of turbine efficiency on unit 3 at Terror Lake Power Plant near Kodiak, Alaska in January/February 2014. The measurements were performed using the thermodynamic method according to the guidelines given in IEC 60041 [1]. The performance guarantee for efficiency is given as a weighted unit efficiency. For verification of the unit efficiency, the measured turbine efficiency has been multiplied with the generator efficiency, which was not measured by Norconsult. The generator efficiency was previously measured, and the results made available. The guarantees given on the unit efficiency are fulfilled. The guaranteed unit output is given at a lower net head than the test head. As the highest load measured was limited by the generator capacity, it was impossible to perform a measurement to verify the guaranteed unit output. Nevertheless, as shown in chapter 2.4, it is probable that the guaranteed unit output is fulfilled. This should however be verified by testing with the correct net head. This is the draft of the measurement report. Both Andritz and KEA should approve of any changes in the report before the final report is issued by Norconsult. 01 2014-03-3 Version 01 — Draft H. Hulaas L. Parr H. Hulaas Revision Date:Description Prepared Checked Approved This document has been prepared by Norconsult AS as a part of the assignment identified in the document. Intellectual property rights to this document belongs to Norconsult AS. This document may only be used for the purpose stated in the contract between Norconsult AS and the client, and may not be copied or made available by other means or to a greater extent than the intended purpose requires. Norconsult AS | P.O.Box 626, NO-1303 Sandvika | Vestfjordgaten 4, NO-1338 Sandvika Assignment no. 5132673 Document no.o502 Revision:01 Terror Lake Unit 3 report.docx 03.03. 2014|Page 3 of 24 Contents 1 INTRODUCTION...................................................................................................................................................5 1.1 ABOUT THIS REPORT .................................................................................................................................................5 2 RESULTS...............................................................................................................................................................6 2.1 GUARANTEES ..........................................................................................................................................................6 2.2 EFFICIENCIES............................................................................................................................................................7 2.3 UNCERTAINTIES .....................................................................................................................................................11 2.4 TURBINE POWER AT FULL LOAD .................................................................................................................................11 2.5 TEST COMMENTS ...................................................................................................................................................12 3 BACKGROUND...................................................................................................................................................13 3.1 ABOUT THE MEASUREMENTS—OBJECT OF TEST ..................................................................................................13 3.2 THE THERMODYNAMIC METHOD ...............................................................................................................................13 3.3 PERSONNEL...........................................................................................................................................................14 3.4 LOG .....................................................................................................................................................................14 4 MEASUREMENT SETUP......................................................................................................................................15 4.1 FIXED AND MEASURED VALUES ..................................................................................................................................15 4.2 PREPARATION OF THE UNITS FOR THE TESTS .................................................................................................................15 4.3 INSPECTION OF THE UNIT .........................................................................................................................................15 4.4 THE TESTS .............................................................................................................................................................15 4.5 TEST SETUP ...........................................................................................................................................................16 5 CHECKS AND FIXED VALUES...............................................................................................................................20 5.1 CHECKS CARRIED OUT AT SITE....................................................................................................................................20 5.2 FIXED VALUES ........................................................................................................................................................20 5.3 GENERATOR EFFICIENCY...........................................................................................................................................20 5.4 THE PHYSICALPROPERTIES OF WATER..........................................................................................................................21 6 CALCULATIONS..................................................................................................................................................22 6.1 LIST OF SYMOBLS ....................................................................................................................................................22 6.2 TURBINE EFFICIENCY ...............................................................................................................................................23 6.3 UNCERTAINTIES .....................................................................................................................................................23 List of figures FIGURE 2-1 UNIT GUARANTEE EFFICIENCY VS FLOW AT SPECIFIED HEAD. ........................................................................8 FIGURE 2-2 UNIT EFFICIENCY VS GENERATOR POWER AT SPECIFIED HEAD.......................................................................9 FIGURE 2-3 TURBINE EFFICIENCY VS TURBINE POWER AT SPECIFIED HEAD. ...................................................................10 Assignment no. 5132673 Document no.o502 Revision:01 Terror Lake Unit 3 report.docx 03.03. 2014|Page 4 of 24 List of tables TABLE 2-1 GUARANTEED AND MEASURED VALUES............................................................................................................6 TABLE 2-2 MEASURED VALUES ...........................................................................................................................................7 TABLE 3-1 LOG...................................................................................................................................................................14 TABLE 4-1 MEASUREMENT EQUIPMENT...........................................................................................................................16 TABLE 4-2 LOCATION OF THERMOMETERS.......................................................................................................................17 Enclosures 1-1 Technical specifications —turbine and generator 2-1 Calculated values 2-2 Measurement uncertainties 2-3 Figure:Estimated guarantee power output at 1136 ft 3-1 Short description of the thermodynamic method 4-1 Fixed and measured values 4-2 Test-and instrument setup 4-3 Measuring vessel at turbine inlet 4-4 Sampling pipes at turbine outlet 4-5 Agilent 34970 thermometer multiplexer 4-6 Pt-100 thermometers calibrations 4-7 Digiquartz pressure gauge 5-1 Thermometer checks on site 5-2 Generator efficiency 5-3 Runner inspection 6-1 Formulas for calculation of efficiency 6-2 Formulas for calculation of uncertainty Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 5 of 24 1 Introduction 1.1 ABOUT THIS REPORT This is the draft report from the efficiency measurements of unit 3 at Terror Lake Hydroelectric Power Plant performed on 1 th and 2 nd February 2014. Both Andritz and KEA should approve of this report before the final report is issued by Norconsult. The purpose of the test was to verify the guarantees given on turbine efficiency and power. The technical specifications of the turbine and generator is given in Enclosure 1-1. The enclosures are numbered according to the chapter where they first appear. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 6 of 24 2 Results 2.1 GUARANTEES The guarantee unit efficiency vs. flow is given in Figure 2-1 on page 8. In calculating the unit efficiency, the generator efficiencies are taken from the Generator Test Report, see Enclosure 5-2/2. The values are compared with the guarantees in Table 2-1 below. Table 2-1 Guaranteed and measured values Guarantee SUM Flow [cfs]20.0 40.0 60.0 80.0 120.0 Unit Efficiency [%]80.73 85.33 86.96 87.51 87.47 Weighing Factor 0.02 0.08 0.24 0.40 0.26 Weighted Efficiency [%]1.61 6.83 20.87 35.00 22.74 87.06 Measured Values (interpolated) Flow [cfs]20.0 40.0 60.0 80.0 120.0 Unit Efficiency [%] 79.26 85.01 86.90 87.48 87.56 Weighing Factor 0.02 0.08 0.24 0.40 0.26 Weighted Efficiency [%] 1.59 6.80 20.86 34.99 22.77 87.00 Weighted Efficiency Including the Uncertainty (± 0.78%)87.78 The guaranteed weighted efficiency at 1275 ft net head is 87.06%. The measured weighted efficiency at 1275 ft net head incl. the uncertainty of ± 0.78% is 87.78%. The guarantee is therefore fulfilled. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 7 of 24 2.2 EFFICIENCIES The turbine, generator and unit efficiency is given in Table 2-2 below. The generator power and flow are referred to the specified net head of 1275 ft using the laws of affinity. The generator efficiencies are interpolated based on previously measured values as documented in Enclosure 5.2. The calculated values are shown in Encl. 2-1. Table 2-2 Measured values Test No. No. Of Needles Test Head [ft] Generator Power at sp. head [MW] Flow at sp. Head [cfs] Turbine efficiency [%] Generator efficiency (ref Encl. 5.2) [%] Unit Efficiency [%] 301 6 1301.86 7.57 79.87 90.42 96.83 87.55 302 6 1302.61 7.57 79.84 90.37 96.83 87.51 303 6 1302.23 7.59 80.12 90.32 96.84 87.46 304 6 1300.82 12.44 131.82 89.33 97.54 87.13 305 6 1301.35 9.72 102.24 90.30 97.27 87.84 306 4 1300.90 7.45 78.78 90.25 96.80 87.36 307 4 1299.71 5.58 59.33 90.44 96.04 86.86 308 4 1299.45 3.82 41.39 90.00 94.59 85.13 309 2 1299.90 3.63 39.44 90.09 94.35 85.00 310 6 1302.23 7.25 76.66 90.23 96.74 87.29 311 2 1301.19 1.78 20.58 89.01 89.41 79.58 312 2 1300.78 2.92 32.06 90.16 93.16 84.00 313 6 1298.67 11.41 120.44 89.79 97.46 87.51 The unit efficiency vs. unit power at specified head is shown in Figure 2-2 on page 9. The turbine efficiency vs. turbine power at specified head is shown Figure 2-3 on page 10. Turbine Type: Rated Output: Rated Head: Rated Speed: Diameter: Pelton vertical 11.47 MW (at 1136 ft) 720 rpm T :2.65 ºC Performed Date: Performed by: Measuring Method: - acc to: Test Head: 1th -2nd Feb 2014 Harald Hulaas Thermodynamic IEC 60041 (1991) New Runner Old Runner Guarantee Refurbishment - after - before X 1298.7 ft - 1302.6 ft Customer:Kodiak Electric Association Project: Document: Thermodynamic Efficiency measurements Unit Efficiency at 1275 ft Net Head Project No.5132673 Date2014-02-28 Sign.H. Hulaas X Terror Lake Power Plant Unit 3 1275 ft 7980818283848586878889900 10 20 30 40 50 60 70 80 90 100 110 120 130 140Guarantee6 Needles4 Needles2 NeedlesUnit efficiency [%]Flow at rated head [cfs] 1060 mm Figure 2-1 Unit Guarantee Efficiency vs Flow at Specified Head. Turbine Type: Rated Output: Rated Head: Rated Speed: Diameter: Pelton vertical 11.47 MW (at 1136 ft) 720 rpm T :2.65 ºC Performed Date: Performed by: Measuring Method: - acc to: Test Head: 1th -2nd Feb 2014 Harald Hulaas Thermodynamic IEC 60041 (1991) New Runner Old Runner Guarantee Refurbishment - after - before X 1298.7 ft - 1302.6 ft Customer:Kodiak Electric Association Project: Document: Thermodynamic Efficiency measurements Unit Efficiency at 1275 ft Net Head Project No.5132673 Date2014-02-28 Sign.H. Hulaas X Terror Lake Power Plant Unit 3 1275 ft 1060 mm Figure 2-2 Unit Efficiency vs Generator Power at Specified Head.7980818283848586878889900 1 2 3 4 5 6 7 8 9 10 11 12 13 14 155 Needles4 Needles2 NeedlesUnit efficiency [%]Generator power at rated head [MW] Turbine Type: Rated Output: Rated Head: Rated Speed: Diameter: Pelton vertical 11.47 MW (at 1136 ft) 720 rpm T :2.65 ºC Performed Date: Performed by: Measuring Method: - acc to: Test Head: 1th -2nd Feb 2014 Harald Hulaas Thermodynamic IEC 60041 (1991) New Runner Old Runner Guarantee Refurbishment - after - before X 1298.7 ft - 1302.6 ft Customer:Kodiak Electric Association Project: Document: Thermodynamic Efficiency measurements Turbine Efficiency at 1275 ft Net Head Project No.5132673 Date2014-02-28 Sign.H. Hulaas X Terror Lake Power Plant Unit 3 1275 ft 1060 mm Figure 2-3 Turbine Efficiency vs Turbine Power at Specified HeadTurbine efficiency [%] Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 11 of 24 2.3 UNCERTAINTY A standard calculation of measurement uncertainty has been made, and the uncertainty in the turbine efficiency is estimated to be ± 0.72%. Assuming the uncertainty in the generator efficiency is ±0.3%, the uncertainty of the unit efficiency is ±0.78%. The flow is calculated within ±0.95%, and the turbine power is within ±0.62%. The spreadsheet calculating the uncertainties is given in Enclosure 2-2. See also Enclosure 6.2 for the calculation formulas. 2.4 GUARANTEED UNIT OUTPUT The guaranteed unit full load power output measured at the generator terminals with 1136 ft net head on the turbine is 11.47 MW. As the highest load measured was limited by the generator capacity, it was impossible to perform a measurement to verify the guaranteed unit output. We have therefore given a calculation below, which shows that it is likely that this guarantee is fulfilled. See Enclosure 2-3. The highest power measured at 1275 ft. is at 12.44 MW and 131.82 cfs (point A). The needle opening is at 65.4% (point B). Using the affinity laws, the corresponding flow and power at 1136 ft. and constant opening (point A’) is: = .=. = 124.43 .. = 10.46 Assuming constant efficiency 1 we extrapolate from point A’ to point A’’ (the guarantee power at 11.47 MW). Reading the values at A’’ from the graph, we get Q’’ = 137.30 cfs P’’ = 11.47 MW 1 There exists a Hill Chart for the turbine, but Norconsult does not currently have access to it. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 12 of 24 By extrapolating the curve for flow vs. needle opening from B’ to B’’ we predict the opening at this point to be 76.8%. As the needle opening of 76.8% is far from the maximum opening of 100%, it is highly probable that the guarantee power of 11.47 MW at 1136 ft. is met. This should however be verified when the net head of 1136 ft. occurs. 2.5 TEST COMMENTS 2.5.1 Test conditions The test conditions were very good with stable temperatures and pressures for all test points. 2.5.2 Net head during the test During the test, the maximum and minimum net head were 1302.6 ft and 1298.7 ft, or 1.86% to 2.17% of specified head. A span of ±2 % in the net head is the limit of the standard IEC 60041 Ch. 6.1.2.2.c for referring the measured turbine power and flow without also correcting the measured turbine efficiency using the turbine Hill chart. The measured efficiencies should therefore be corrected using the procedure above. As the Hill chart of Terror Lake unit 3 from Andritz has not been made available for the Chief of Test, this correction is not performed. KEA has to approve this before the final report is issued. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 13 of 24 3 Background 3.1 ABOUT THE MEASUREMENTS — OBJECT OF TEST Norconsult AS was engaged by KEA to perform measurement of turbine efficiency on unit 3 at Terror Lake Power Plant near Kodiak, Alaska in January/February 2014. The measurements were performed using the thermodynamic method according to the guidelines given in IEC 60041 [1]. Representatives from both Andritz S.A. and KEA were present during the measurements. 3.2 THE THERMODYNAMIC METHOD The thermodynamic method results from the application of the principle of conservation of energy (first law of thermodynamics) to a transfer of energy between water and the runner/impeller through which it is flowing. The specific mechanical energy at the runner may be determined by measurement of the performance variables (pressure, temperature, velocity and level) and from the thermodynamic properties of water. To establish the efficiency, the need to measure the discharge is eliminated by using the specific mechanical energy together with the specific hydraulic energy. A short summary of the thermodynamic method is given in Enclosure 3-1. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 14 of 24 3.3 PERSONNEL The test was performed by: Harald Hulaas Norconsult AS, Norway Present during the measurements: Linsay Bernrot Andritz Hydro Daniel J. Hertrich HATCH 3.4 LOG Table 3-1 shows the time schedule of the installation and tests. Table 3-1 Log Date Time Task 2014-01-30 16:00 Arrival Terror Lake power plant 2014-01-31 07:30 - 10:00 Pre-test meeting about the measurements and governor settings 10:00 - 16:00 Instrument set-up and checking 2014-02-01 07:00 - 09:00 Finalizing test set-up. Bleeding of pressure lines. 09:00 - 10:00 Thermometer zero checks 11:00 - 11:30 Distribution of thermometers 12:00 - 12:20 Efficiency test point no 301 12:20 - 12:40 Test point 302; Exchange of the inlet and main outlet thermometer to verify zero. 12:50 - 19:00 Test point 303 – 309. Thermometer check 2014-02-02 07:00 - 07:40 Thermometer check 07:45 - 12:00 Test point 310 – 313. 12:00 - 12:30 Thermometer check 13:00 - 18:00 Dismantling of instruments, packing 2014-02-03 09:30 Leaving site Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 15 of 24 4 Measurement setup 4.1 FIXED AND MEASURED VALUES The fixed and measured values are given in Enclosure 4-1. 4.2 PREPARATION OF THE UNITS FOR THE TESTS The measuring vessel at the inlet and the measuring pipes at the outlet were mounted. The cooling water upstream the thermometers at the outlet was diverted downstream the thermometers using a temporarily installed plastic pipe. The brook intakes were not closed or diverted during the test. 4.3 INSPECTION OF THE UNIT The runner was inspected. No significant wear was observed. See Enclosure 5-2. 4.4 THE TESTS For checks done before and after the tests, see Chapter 5. 4.4.1 Observations during the tests No special incidents were observed during the measurements. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 16 of 24 4.5 TEST SETUP The test setup and the location of the instruments are shown in Enclosure 4-2. The figure shows both electric and hydraulic connections. Table 4-1 summarizes the equipment used for the test. The measuring vessel at inlet is shown in Enclosure 4-3, and the sampling pipes at the outlet are given in Enclosure 4-4. Table 4-1 Measurement equipment Measurement Instrument Spec ID / comm. Temperature Turbine inlet 1-1 Agilent 34970A Data acquisition unit. Enclosure 4-5 s/n 44010890 Temperature difference 1-1 2-1 Pt-100 thermometers Enclosure 4-6 Table 4-2 Pressure Pipe wall inlet pabs1’Paroscientific Digiquartz Enclosure 4-7 s/n 115416 Inlet temperature probe pabs1-1’762-1K pressure transducer Atmospheric pressure Power Generator power Pg MWh-meter Power plant instrumentation Stop watch Turbine opening Servo motor stroke s Read at governor Power plant instrumentation Flows Inlet temperature probe qrot Kylala rotameter 0-10 l/min Water level Tail water level ZTWL Measuring band with beeper signal YAMAYO Million Data acquisition Pressures and temperatures PC Other equipment Inlet temperature probe Norconsult design Enclosure 4-3 Outlet temperature frame Enclosure 4-4 Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 17 of 24 4.5.1 Temperature The thermometers were located as shown Table 4-2 below. Table 4-2 Location of thermometers Thermo- meter Channel Measured parameter Location 11 Probe at turbine inlet. Cable length 30 m 21 Centre pipe Turbine outlet, centre pipe. Cable length 30 m 22 Right pipe Turbine outlet, right pipe. Cable length 30 m 23 Left pipe Turbine outlet, left pipe. Cable length 30 m To measure pressure and temperature of the water on the inlet of the turbine, a pitot probe measuring vessel was used as shown in Enclosure 4-3. The probe had a DN50 flange and was mounted on the flange for the spiral case aeration. At the turbine outlet three perforated pipes were set. One thermometer was used in each pipe, and moved to two different heights for each measurement point. Thus the temperatures were measured at 6 points for each test point. See Enclosure 4-4. All temperatures were recorded for a period of at least 3 minutes. The average values from the period are used in the calculations. The temperature curves/files are not attached in this report, but are available from our archive. 4.5.2 Pressures Pipe wall pressures downstream of the main inlet valve: The pressure downstream of the main inlet valve was measured by the precision pressure gauge using four connected pressure taps. Pressure in inlet temperature probe: The pressure by the thermometer in the inlet temperature probe was measured by the precision pressure gauge through the pressure taps of the probes. All pressures were connected to the same precision pressure transducer via a manifold of valves. The measured pressures are referred to the level of the precision pressure gauge. The pressures were recorded on the computer for at least three minutes at the same time as the temperature difference over the turbine was recorded. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 18 of 24 The recorded values of the precision pressure gauge are not given in the report, but are available from our archive. Ambient pressure: The ambient pressure was read from a barometric Tissot T-touch watch during the measurements. The readings were verified by the precision pressure transducer at the end of the measurements. The atmospheric pressure was read of each test run. 4.5.3 Water levels The water level at the outlet was measured using a measuring band with a beeper signal. The reference of the measurement was the floor above the tail water level. The level at the outlet was measured once per test run. Several consecutive measurements were made, and the values averaged to obtain the value used in the calculations. 4.5.4 Needle opening The needle opening was read at the governor screen. The opening was given in [%]. 4.5.5 Generator power The generator power, active and reactive, was read from the instrumentation of the power plant. In addition to manual readings from the display in the control room, the active generator power was calculated by recording the kWh-meter during a time period measured by a stop watch. The displayed active and reactive powers were read once per test run. The readings of the kWh-meter were performed during a 10 min period of the test run 4.5.6 Other measurements The flow through the inlet probe were measured using a rotameter. The flow in the turbine inlet temperature probe was adjusted to 4 l/min. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 19 of 24 4.5.7 General test procedures The thermodynamic method was performed by the direct method according to guidelines given in IEC 60041, 3. ed. 1991-11 [1]. The test runs were started as soon as the temperature difference over the turbine had stabilized, and the pressure variation in the penstock due to the change in unit load had reduced sufficiently. The measuring sequence was: 1. Piezometer pressure at inlet pipe 2. Measuring vessel pressure, temperature and temperature difference between inlet and outlet 3. The thermometers were moved to the next height (upper or lower pos). 4. Repeat 1 or 2 for check The sequence 1 – 3 would be altered to suit the situation in order to save time. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 20 of 24 5 Checks and fixed values 5.1 CHECKS CARRIED OUT AT SITE 5.1.1 Check of thermometers To record an eventual drift in the thermometers during the test, checks of zero difference temperature of the thermometers were performed before and after the test. The checks were made by putting all thermometers together in one of the perforated pipes at the outlet while the unit was running and water flowing past the pipe. See Enclosure 5-1. Also for test point 302 the inlet thermometer was swapped with the main thermometer at the outlet during the same turbine set-point. The difference between the measured temperature difference in test 301 and 302 was well within 1 mK. 5.2 FIXED VALUES All fixed values used in the calculations are given in Enclosure 4-1/1. 5.2.1 Levels The level of the turbine centre, the turbine floor and the reference level of the draft tube outlet level measurement are taken from drawings and ref /2/. The level of the precision pressure gauge and the thermometers on the turbine outlet were measured at site. 5.2.2 Inlet and outlet flow area The diameter on the inlet pressure measurement section and the draft tube outlet flow area are taken from drawings. 5.3 GENERATOR EFFICIENCY The generator efficiency used in the calculations is shown Enclosure 5-2. The curve was handed over from KEA before the measurements started. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 21 of 24 5.4 RUNNER INSPECTION The runner was inspected by Andritz before the measurements. The inspection report is given in Enclosure 5-3. 5.5 THE PHYSICAL PROPERTIES OF WATER p, are calculated according to formulas specified in Enclosure 5-1, IEC 60041. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 22 of 24 6 Calculations 6.1 LIST OF SYMOBLS Symbols A - area m 2 a - isothermal factor m 3/kg cp - specific heat capacity J/kg °C d - diameter m E - specific hydraulic energy J/kg Em - specific mechanic energy J/kg e - absolute uncertainty f - relative uncertainty % g - specific gravity m/s 2 H - head m j - loss % el. M n - unit speed o/min P - power MW p - pressure bar Q - flow m 3/s s - servo motor stroke mm T - temperature °C t - time s v - velocity m/s z - level m z1’ - level of precision pressure gauge m z2’ - water level at draft tube outlet m - efficiency % - temperature C - density kg/m 3 Indices 0 - measurement section at the inlet of the turbine, upstream of the main inlet valve 1 - measurement section at the inlet of the turbine, upstream of the main inlet valve 11 - thermometer at turbine inlet 2 - measurement section at turbine outlet 21 - thermometer at turbine outlet 3 - measurement location of leakage flow from the upper labyrinth seal abs - absolute amb - atmospheric G - generator i - precision pressure gauge (instrument) n - nominal values ov - headwater T - turbine uv - tailwater wk - Winter-Kennedy Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 23 of 24 6.2 TURBINE EFFICIENCY The formulas and a sample calculation is given in Enclosure 6-1. The input data for the calculations are given in Enclosure 4-1. The calculated values are given in Enclosure 2-1 in spreadsheet format. The calculations are performed according to the guidelines given in the standard IEC 60041, 3. ed. 1991-11 [1]. Deviations from zero differential pressure between the thermometers are taken into account in the determination of the temperature differences, by taking the average of the deviation measured before and after the test. Furthermore, for the final determination of the temperature differences, the temperature-dependent deviation from zero differential pressure is also taken into account. The velocity in the water flowing past the inlet and outlet thermometers is not taken into account in the calculations because: • the inlet probe is designed in such a way that the velocity head is measured together with the static head p11 in the probe. • the flow velocity past the outlet thermometer is small, and may be disregarded. These simplifications have negligible influence on the results. 6.3 UNIT EFFICIENCY The unit efficiency is calculated from the measured turbine efficiency and the generator efficiency. The generator efficiency (see Enclosure 5.2) was previously measured - not by Norconsult. The given generator efficiencies are interpolated using a polynomial for the generator loss. All bearing losses are included in the generator efficiency. 6.4 UNCERTAINTIES Standard calculations of uncertainty are used, with calculation of both random and systematic uncertainties. The uncertainty analysis is presented in Enclosure 6-2. The input data for the calculations are given in Enclosure 4-1. The calculated uncertainties are given in spreadsheet format in Enclosure 2-1. Terror Lake Power Plant Unit 3 Draft Report — Thermodynamic efficiency measurements Terror Lake Unit 3 report.docx 2014-03-03 |Page 24 of 24 References /1/IEC 60041 "Field acceptance tests to determine the hydraulic performance of hydraulic turbines, storage pumps and pump turbines", 3. ed. 1991-1 /2/Terror Lake Hydroelectric Power Plant, Turbine efficiency measurements, unit no 1 & no. 2, Head loss tests, 18 – 20 July 2006. Norconsult report 18 th August 2006. Enclosure 1-1/1 Enclosure 1-1/2 Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 Calculated values 2-1/1 VGM /41/NC/8.12 5132673 Terror Lake Turbin 3 01-f eb-2014 Test No 301 302 303 304 305 306 Time 12.10 12.10 12.50 14.50 15.40 16.40 No of needles [mm]6 6 6 6 6 4 Pressure at 1 p1 [kPa]3977.7 3979.9 3978.6 3933.8 3961.0 3975.5 Pressure at 2 p2 [kPa]102.3 102.3 102.3 102.4 102.3 102.3 Pressure at 1-1 p1-1 [kPa]3996.6 3998.0 3996.0 3985.1 3989.7 3990.9 Pressure at 2-1 p2-1 [kPa]106.2 106.2 106.2 104.4 103.3 105.2 Altitude Tail Water Level zTWL [m]29.65 29.7 29.7 29.5 29.4 29.6 Isothermal coeff. Em1-1 a 10 -3 [m 3/kg]1.00366 1.00365 1.00333 1.00307 1.00302 1.00291 Specific heat capacity Em1-2 cp [J/kg K]4195.8 4195.8 4195.8 4195.8 4195.8 4195.7 Density, inlet [kg/m3]1001.89 1001.89 1001.89 1001.89 1001.89 1001.89 Density, E [kg/m3]1000.92 1000.92 1000.92 1000.91 1000.92 1000.92 Density, outlet [kg/m3]999.96 999.96 999.96 999.96 999.96 999.96 Em1-2, Pressure term ap [J/kg]3904.6 3906.0 3902.8 3892.7 3898.2 3896.9 Em1-2, Temperature term cp[J/kg]-406.9 -408.1 -407.9 -440.1 -406.3 -408.2 Em1-2, Potential term g(z11-z22)[J/kg]24.5 24.5 24.5 24.5 24.5 24.5 Mechanical Energy Em [J/kg]3522.2 3522.4 3519.4 3477.1 3516.4 3513.2 Turbine Power PT [MW]8.06 8.06 8.09 13.13 10.30 7.93 Turbine Discharge Q [m 3/s]2.29 2.29 2.29 3.77 2.92 2.25 Velocity, High Pressure Side v1 [m/s]6.89 6.89 6.91 11.36 8.81 6.79 E, Pressure term 1/*p [J/kg]3871.8 3874.1 3872.8 3827.9 3855.2 3869.6 E, Velocity term v2/2 [J/kg]23.7 23.7 23.9 64.6 38.8 23.1 E, Potential term gz Hydraulic Energy E [J/kg]3895.6 3897.8 3896.6 3892.4 3894.0 3892.7 Turbine Efficiency [%]90.42 90.37 90.32 89.33 90.30 90.25 Head H [m]396.81 397.03 396.92 396.49 396.65 396.51 Head H [ft]1301.9 1302.6 1302.2 1300.8 1301.3 1300.9 Rated Turbine Power Prt [MW]7.82 7.81 7.83 12.75 9.99 7.70 Rated Discharge Qrt [m 3/s]2.3 2.3 2.3 3.7 2.9 2.2 Rated Discharge Qrt [cfs]79.9 79.8 80.1 131.8 102.2 78.8 Uncertainty in Efficiency f()[%]0.72 0.72 0.72 0.72 0.72 0.72 Uncertainty in Flow f(Q)[%]0.94 0.94 0.94 0.95 0.94 0.94 Uncertainty in Power f(PT)[%]0.62 0.62 0.62 0.62 0.62 0.62 Rated Generator Power Pg,rt [MW]7.57 7.57 7.59 12.44 9.72 7.45 Generator effic iency g [%]96.83 96.83 96.84 97.54 97.27 96.80 Unit efficiency tot [%]87.55 87.51 87.46 87.13 87.84 87.36 Deviation from rated head 2.11 % 2.17 % 2.14 % 2.03 % 2.07 % 2.03 % Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 2-1/2Calculated values V GM /41/NC/8.12 5132673 Terror Lake Turb in 3 0 1-feb-2014 Test No 307 308 309 310 311 312 313 Time 17.30 18.20 19.10 7.45 8.50 9.40 11.30 No of needles [mm]4 4 2 6 2 2 6 Pressure at 1 p1 [kPa]3981.9 3988.0 3989.9 3980.7 3997.9 3994.4 3938.0 Pressure at 2 p2 [kPa]102.3 102.4 102.4 102.3 102.3 102.3 102.3 Pressure at 1-1 p1-1 [kPa]3990.0 3990.8 3990.2 3997.0 3996.6 3992.8 3978.2 Pressure at 2-1 p2-1 [kPa]105.2 105.3 104.8 105.2 104.7 104.3 104.3 Altitude Tail Water Level zTWL [m]29.6 29.6 29.5 29.6 29.5 29.5 29.5 Isothermal coeff. Em1-1 a 10 -3 [m 3/kg]1.00276 1.00264 1.00264 1.00306 1.00308 1.00302 1.00292 Specific heat capacity Em1-2 cp [J/kg K]4195.7 4195.7 4195.7 4195.7 4195.7 4195.7 4195.8 Density, inlet [kg/m3]1001.89 1001.89 1001.89 1001.89 1001.89 1001.89 1001.88 Density, E [kg/m3]1000.93 1000.93 1000.93 1000.92 1000.93 1000.93 1000.91 Density, outlet [kg/m3]999.96 999.96 999.96 999.96 999.96 999.96 999.96 Em1-2, Pressure term ap [J/kg]3895.5 3895.7 3895.6 3903.6 3903.9 3900.3 3885.2 Em1-2, Temperature term cp[J/kg]-402.8 -420.8 -416.1 -412.2 -462.9 -415.4 -420.7 Em1-2, Potential term g(z11-z22)[J/kg]24.5 24.5 24.5 24.5 24.5 24.5 24.5 Mechanical Energy Em [J/kg]3517.2 3499.4 3504.1 3515.9 3465.5 3509.4 3489.1 Turbine Power PT [MW]5.98 4.15 3.96 7.73 2.04 3.22 12.03 Turbine Discharge Q [m 3/s]1.70 1.18 1.13 2.19 0.59 0.92 3.44 Velocity, High Pressure Side v1 [m/s]5.11 3.57 3.40 6.61 1.77 2.76 10.37 E, Pressure term 1/*p [J/kg]3876.1 3882.0 3883.9 3874.8 3892.0 3888.5 3832.2 E, Velocity term v2/2 [J/kg]13.1 6.4 5.8 21.9 1.6 3.8 53.8 E, Potential term gz Hydraulic Energy E [J/kg]3889.1 3888.4 3889.7 3896.7 3893.5 3892.3 3886.0 Turbine Efficiency [%]90.44 90.00 90.09 90.23 89.01 90.16 89.79 Head H [m]396.15 396.07 396.21 396.92 396.60 396.48 395.84 Head H [ft]1299.7 1299.5 1299.9 1302.2 1301.2 1300.8 1298.7 Rated Turbine Power Prt [MW]5.81 4.03 3.85 7.49 1.98 3.13 11.70 Rated Discharge Qrt [m 3/s]1.7 1.2 1.1 2.2 0.6 0.9 3.4 Rated Discharge Qrt [cfs]59.3 41.4 39.4 76.7 20.6 32.1 120.4 Uncertainty in Efficiency f()[%]0.72 0.72 0.72 0.72 0.72 0.72 0.72 Uncertainty in Flow f(Q)[%]0.95 0.95 0.95 0.94 0.96 0.95 0.94 Uncertainty in Power f(PT)[%]0.62 0.62 0.63 0.62 0.63 0.63 0.62 Rated Generator Power Pg,rt [MW]5.58 3.82 3.63 7.25 1.78 2.92 11.41 Generator efficiency g [%]96.04 94.59 94.35 96.74 89.41 93.16 97.46 Unit efficiency tot [%]86.86 85.13 85.00 87.29 79.58 84.00 87.51 Deviation from rated head 1.94 % 1.92 % 1.95 % 2.14 % 2.05 % 2.02 % 1.86 % Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 Uncertainty Analysis 2-2 VGM/41/NC/8.12 5132673 Terro r Lake Turbin 3 0 1-feb -2014 Test No 301 Time 12.10 No of needles 6.0 Spec. mechanical energy, Em1-2 Pressure terms * a·epabs11 [J/kg]±4.0 * a·epabs21 [J/kg]±1.4 * (pabs11 - pabs21)·ea [J/kg]±7.8 * eEp e(Ep)[J/kg]±8.9 Temperature terms * (T11 - T21)·ecp [J/kg]±2.0 * cp·e(T11-T21)[J/kg]±4.2 * energy distribution inlet, eE10 [J/kg]±7.0 * energy distribution outlet, eE20 [J/kg]±21.1 * eET e(E )[J/kg]±22.8 Elevation terms * g·ez11 [J/kg]±0.5 * g·ez21 [J/kg]±1.0 * eEz e(Ez)[J/kg]±1.1 Corrective terms * edEm1-2 e(dEm1-2)[J/kg]±0.0 Rss-sum * eEm1-2 e(Em1-2)[J/kg]±24.5 *fEm f(Em)[%]±0.69 Spec. hydraulic energy, E Pressure terms * 1/·e pabs1 [J/kg]±4.0 * 1/·e p2 [J/kg]±0.1 *1/2·(p abs1 - p abs2)·e [J/kg]±3.9 *e Ep e(Ep)[J/kg]±5.5 Velocity terms * v1·e v1 [J/kg]±0.4 * v2·e v2 [J/kg] *e Ev e(Ev )[J/kg]±0.4 Elevation terms * g·ez1 [J/kg]±0.1 * g·ez2 [J/kg]±0.1 *eEz e(Ez)[J/kg]±0.1 Corrective terms * edE e(dE)[J/kg]±0.0 Rss-sum *eE e (E)[J/kg]±5.5 *fE f(Em)[%]±0.14 Turbine Power e(PT)[MW]±0.05 Turbine Discharge e(Q)[m 3/s]±0.02 Turbine Power f(PT)[%]±0.59 Turbine Discharge f(Q)[%]±0.92 Efficiency f(Eta)[%]0.71 Test No 301 Time 12.10 No of needles 6.0 Spec. mechanical energy, Em1-2 Pressure terms * a·epabs11 [J/kg]±0.4 * a·epabs21 [J/kg]±0.0 * (pabs11 - pabs21)·ea [J/kg]±0.0 * eEp e(Ep)[J/kg]±0.4 Temperature terms * (T11 - T21)·ecp [J/kg]±0.0 * cp·e(T11-T21)[J/kg]±4.2 * energy distribution inlet, eE10 [J/kg]±0.0 * energy distribution outlet, eE20 [J/kg]±0.0 * eET e(E )[J/kg]±4.2 Elevation terms * g·ez11 [J/kg]±0.0 * g·ez21 [J/kg]±0.0 * eEz e(Ez)[J/kg]±0.0 Corrective terms * edEm1-2 e(dEm1-2)[J/kg]±0.0 Rss-sum * e Em1-2 e(Em1-2)[J/kg]±4.2 * fEm f(Em)[%]±0.11 Spec. hydraulic energy, E Pressure terms * 1/·e pabs1 [J/kg]±0.4 * 1/·e p2 [J/kg]±0.0 * 1/2·(p abs1 - p abs2)·e [J/kg]±0.0 * e Ep e(Ep)[J/kg]±0.4 Velocity terms * v1·e v1 [J/kg]±0.1 * v2·e v2 [J/kg] * e Ev e(Ev )[J/kg]±0.1 Elevation terms * g·ez1 [J/kg]±0.0 * g·ez2 [J/kg]±0.0 * eEz e(Ez)[J/kg]±0.0 Corrective terms * edE e(dE)[J/kg]±0.0 Rss-sum * e E e(E)[J/kg]±0.4 * fE f(Em)[%]±0.01 Turbine Power e(PT)[MW]±0.02 Turbine Discharge e(Q)[m3/s]±0.01 Turbine Power f(PT)[%]±0.20 Turbine Discharge f(Q)[%]±0.23 Efficiency f(Eta)[%]0.11 Total Uncertainty Uncertainty in Efficiency f()[%]0.72 Uncertainty in Flow f(Q)[%]0.94 Uncertainty in Power f(PT)[%]0.62 Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 Flow vs Needle Openingat 1275 ft Net HeadFlow vs Generator Powerat 1275 ft Net HeadFlow vs Needle Openingat 1136 ft Net HeadFlow vs Generator Powerat 1136 ft Net HeadNeedle opening [%] Generator Power [MW]Extrapolatedto 11.47 MW 2-3Estimated guarantee power at 1136 ft ENCLOSURE 3 x:\nor\oppdrag\sandvika\800\vannkraft\8000000\avdeling.hyd\100079 hydrauliske målinger\rapporter\o1000 maler\engelsk\3 description of thermodynamic method.doc 12.06.2012 A BRIEF DESCRIPTION OF THERMODYNAMIC EFFICIENCY MEASUREMENT The method is based on measuring the total energy (thermal, kinetic and potential) entering and leaving the turbine. The energy is measured per unit mass of water and therefore it is not necessary to measure the total flow. Simplified we have, according to the law of conservation of energy ("the first law of thermodynamics") this relation: Em Energy "produced" (mechanical energy delivered to the shaft) + Ej Energy loss (friction- and hydraulic losses) = E Total available energy for the turbine (related to the hydraulic net head) The general expression of turbine efficiency:T = Em/E = (E - Ej)/E A thermodynamic measurement using the direct method 1 actually determines Ej. Losses 2 in the turbine are transferred to the water resulting in a temperature increase. The temperature increase is measured as a temperature difference between the inlet probe(s) and outlet probe(s). Other necessary measurements such as pressures, elevations, generator output etc. are about the same as for any other efficiency test method. However, it is not necessary to measure the generator output very accurate as it is only of minor importance for calculation of efficiency. To understand the relation between temperature increase and turbine losses it is useful to remind of the basic laws of physics for transition of from potential energy to heat energy: - If m kg water is in a reservoir H meters above the tail water, it represents potential energy equivalent to Epotential = m·g·H. Here g is gravity (9.81 m/s 2). - If water is heated the relation between temperature increase and heat energy is Eheat = m·cp· where cp is the water’s specific heat (4200 J/(kg·C)) and temperature increase. - Imagine that the potential energy of the water in a reservoir Epotential completely is transferred to heat Eheat by discharging it freely through a valve at the tail water level. The temperature increase resulting from this can be found by combining the two equations for equal energies 3. In metric units we get:H = 428·[m]. An example can illustrate this for a thermodynamic measurement. Assume a hydropower unit with net head H=428 m. The temperature difference between inlet and outlet is measured to be:= 0.1 °C. The relation above lets us convert this to a head loss: Hloss= 428·0.1 = 42.8 m. Consequently the turbine efficiency (the ratio: "produced" energy / available energy) becomes: T= (428 - 42.8)/428 = 0.9, i.e. 90% efficiency This description is very simplified and explains only the principle of measurement. For details the appropriate standard is: International Standard IEC 41, 3. ed. 1991-11. 1 Two methods exist; the direct (covered here) and the indirect (partial expansion method). Today the direct method is mostly used. The principal for the indirect method is that water from the turbine inlet probe is discharged through a throttling valve. The valve is adjusted until the throttling gives a temperature after the valve equalto the temperature measured at the outlet of the turbine. The turbine efficiency is then the ratio: (turbine nethead - valve pressure drop) / (turbine net head). 2 Meaning hydraulic losses; boundary friction, singular losses, turbulence etc. 3 All the potential energy is transferred to pressure, then converted to velocity through the valve, which further turns into heat in the turbulence after the valve. Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 Fixed values 4-1/1 Kunde KEA Plant Terror Lake Turbine No 3 Project No 5132673 Date februar-14 Signature Hulaas Rated Output [MW] 11.789 Rated Speed [rpm] 720 Rated Head [mVs] 388.62 Width, Draft tube gate [m]99999 Hight, Draft tube gate [m]99999 Diameter, Inlet [m] 0.6500 Area, Inlet [m] 0.3318 Altitude pressure transducer [m] 33.02 Altitude T1-1 [m] 31.34 Altitude T1-2 [m] 29.25 Altitude floor over outlet [m] 32.15 Altitude bottom of outlet [m] 28.80 Altitude inlet pipe Centre [m] 31.55 Altitude average jet contact [m] 31.55 Constant, kWh-meter 0.001 Latitude of Power Plant 57.70 Altitude of Runner [m] 31.55 Gravity [m/s 2] 9.8172 Uncertainty in:Systematic Random Pressure Transducer p1-1 [%] ±0.10% ±0.01% Pressure Transducer p' [%] ±0.10% ±0.01% Pressure Transducer pamb [%] ±0.10% ±0.01% Altitude of Ztr [m] ±0.01 Altitude of ztwl [m] ±0.10 Altitude of z1-1 [m] ±0.05 Altitude of z2-1 [m] ±0.10 Altitude of z1 [m] ±0.01 Altitude of z2 [m] ±0.01 Altitude of z3 [m] ±0.05 Temperature T1-1 [°C] ±0.01 ±0.001 [°C] ±0.001 ±0.001 Energy Distribution at 1-1, E10 [%] ±0.20% Energy Distribution at 2-2, E20 [%] ±0.60% Density of water [%] ±0.10% Isothermal factor of water a [%] ±0.20% Specific heat capacity of water cp [%] ±0.50% Turbine inlet flow area A1 [%] ±0.10% Turbine outlet flow area A2 [%] Generator Power [MW] ±0.50% ±0.20% Generator Efficiency [MW] ±0.30% Additional terms [%] Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 Measured values 4-1/2 [MW][MVar][s]uv[m]rot[l/min]amb[kPa]abs1'[kPa]abs1-1'[kPa]1-1[°C][°C]gen[MW]gen[%]T2-1[m][]1121[°C]1122[°C]1122[°C]1121[°C]1122[°C]1122[°C][%][%][%][%][%][%] Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 3Bleeding Rotameter Measuring Vessel tapping Test set-up 4-2/1 Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 SeenupstreamABCDXXXDiameter AreaNo of tapsDiameterAreaNo of tapsinsert lenght zNo of vesselsPressureXXXXThermometerUsedNot usedCollected SeparatedUsedNot usedUsed only for calibrationCollectedSeparatedDownstr. MIVPlaced at vent valvSep. locationOther locationUpstr. MIVModel A6 pitots4 pitotsOO270180090Used only for calibrationThermometerAs seen from AModel BModel CModel DMovable todifferentheightsThermometer 31.55 m90270O180028.80 mXOOx4-2/2 29.25 m32.28 m Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 4-3Measuring vessel Measuring vessel DN50 Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 4-4Perforated pipes at outlet AAFlowSection A-APerforated pipesThermometer ThermometerThermometer Enclosure 4.5/1 Enclosure 4.5/2 Enclosure 4.5/3 Enclosure 4.5/4 Enclosure 4.5/5 Enclosure 4-6/1 Enclosure 4-6/2 Enclosure 4-6/3 Enclosure 4-6/4 Enclosure 4-6/5 Enclosure 4-6/6 Enclosure 4-6/7 Enclosure 4-6/8 Enclosure 4-6/9 Enclosure 4-6/10 Enclosure 4-6/11 Enclosure 4-6/12 Enclosure 4-6/13 Enclosure 4-6/14 Enclosure 4-6/15 Enclosure 4-6/16 Enclosure 4-6/17 Enclosure 4-6/18 Enclosure 4-6/19 Enclosure 4-6/20 Enclosure 4-6/21 Enclosure 4-7/1 Enclosure 4-7/2 Enclosure 4-7/3 Enclosure 4-7/4 Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 5-1Thermometer controll Dato 2012-02-01 2012-02-02 2012-02-02 Time 09:17 07:00 12:00 Water temp 1-1 [°C]3.632 3.830 3.720 11-21 [°C]0.0000 0.0001 -0.0001 11-22 [°C]0.0002 0.0003 -0.0001 11-22 [°C]0.0006 -0.0002 -0.0004 Diff temp -0.003 -0.002 -0.001 0.000 0.001 0.002 0.003 Date, Time - - - Zero check of thermometers Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 5-2/1Generator Efficiency Client:KEA Project: Thermodynamic efficiency meaasurements Pr. No.5132673 Date2014-02-15 Sign. Page H. Hulaas Terror Lake Power Plant Unit 3 Generator Efficiency 5-2/1 Generator efficiency [%] Page 1 of 2 RUNNER INSPECTION REPORT Andritz Hydro Inc. Report number: N/A Power house: Terror Lake AL Unit : 3 Date: January 31st, 2014 Initiated by: Customer request Deviation report Intervention report X Others: Norconsult (Harald Hulaas) Subject:Efficiency Test report Description:Runner and Nozzle Inspection Prior to conducting the efficiency test it was required to inspect the runner for any defects that may impact the results. While the unit was shut down we entered the tailrace and inspected the runner and nozzles. A couple of spots were noticed on the runner to have what seemed to be paint or epoxy on it, but these were on the edges and appeared to not be of concern. Nozzle #4 appeared to have some sort of a small scratch on the nose cone, but when inspected by hand it was discovered to be negligible. The runner appeared to be in excellent condition. Pictures shown below: Enclosure 5-3/1 Page 2 of 2 Enclosed report: Yes X No Following intervention (s) to come: Yes No Planned date: People attending: Lindsay Bernrot Customer: (Lloyd Shanley) Hatch :Dan Hertrich, (Joe Earsley) Norconsult: (Harald Hulaas) Note: The name of involved persons, but not necessarily present, should be within parenthesis. Prepared by: Lindsay Bernrot Date: January 31, 2014 Enclosure 5-3/2 THERMODYNAMIC EFFICIENCY MEASUREMENTS FORMULAS AND SAMPLE CALCULATION 28.02.2014 1 Enclosure 6.1/1 THERMODYNAMIC EFFICIENCY MEASUREMENTS The formulas for calculating the efficiency are given in the following, together with a sample calculation. Note that deviations from this sample calc and the values in the spreadsheet are due to rounding errors. Measured values, test point 301 Table 1 Measured values, test point 301 pamb [kPa] - Ambient pressure = 102.3 A1 [m2] - Area of the high pressure side = 0.3318 PG [MW] - Generator power = 7.814 g [m/s 2] - Gravity = 9.8172 z 1'[m] - Level of pressure transducer high pressure side = 33.02 z 1-1 [m] - Level of thermometer 1-1, High pressure side = 31.75 z 2-1 [m] - Level of thermometer 2-1, Low pressure side = 29.25 z 1 [m] - Level of turbine centre = 31.55 pabs 11' [kPa] - Measuring vessel pressure high pressure side = 3984.2 p abs 1' [kPa] - Pipe wall pressure high pressure side = 3963.3 G [Hz] - Generator efficiency = 96.90 1-1 [°C] - Temperature at the high pressure side = 2.513 [°C] - Temperature difference = -0.0970 THERMODYNAMIC EFFICIENCY MEASUREMENTS FORMULAS AND SAMPLE CALCULATION 28.02.2014 2 Enclosure 6.1/2 The Turbine Efficiency The efficiency is given by m T E E [%] Em is the mechanical energy of the water, and E is the hydraulic energy of the water. The relationship between E and net head Hn is E = H .g Calculation of Isothermal Coefficient and Specific Heat Capacity For calculation of the isothermal coefficient and specific heat capacity the average conditions at point 1-1 (the inlet vessel) and 2-1 (at the outlet frame) have to be used. The pressure in the measuring vessel is 11 11' 1' 11 33.02 31.75 1000.92 9.81723984.2 3996.6 kPa1000 absp p z z g The pressure at the outlet thermometer is 21 21 1000 29.65 29.25 999.96 9.8172 102.3 106.2 kPa1000 twl amb z z gp p The mean absolute pressure between inlet and outlet is 11 21 3996.6 106.2 2051.42 2 aver p pp kPa The mean temperature between inlet and outlet is 1 1 2 1 1 1 2 2 2.513 ( 0.0975)2.562 C2 2 2 aver a and pC is taken from tables or formulas THERMODYNAMIC EFFICIENCY MEASUREMENTS FORMULAS AND SAMPLE CALCULATION 28.02.2014 3 Enclosure 6.1/3 3-3a= 1.00366 10 m kg and 4195.8 J kg CpC Calculation of Density For calculation of density the average conditions at turbine inlet and turbine outlet have to be used. The average pressure between outlet and inlet is approximately 1' 1' 1 2' 2' 11 2 2 2 3963.3 102.3 2032.82 p g z z p g z zp pp kPa The average temperature is 11 21 2.562 C2aver 3 is taken from tables and formulas 1000.92 kg m Mechanical Energy The mechanical energy is given by 2 2 1 1 2 1 1 1 2 1 (1 1)(2 1) 1 1 2 1 =2 m p T V Z p E E E E E V Va p p C g z z Pressure Term 11 21 -3 31.00366 10 3996.6 106.2 10 3904.6 J kg pE a p p THERMODYNAMIC EFFICIENCY MEASUREMENTS FORMULAS AND SAMPLE CALCULATION 28.02.2014 4 Enclosure 6.1/4 Temperature Term (11)(21) 4195.8 0.0970 407.0 J kg T p E C Velocity Term The pressure measured in the measuring vessel is the total pressure, including the velocity head, and the same is the case for the measuring frame at the outlet. Thus the velocities are included in the pressure term 2 2 1 1 2 1 02V V VE Potential Term 11 21 =g z 9.8172 31.75 29.25 24.5 J kg ZE z Total Mechanical Energy 3904.6 407.0 0 24.5 3522.2 J kg m p T V z E E E E E Turbine Power and Discharge To calculate the flow, we need the value of the density at the high-pressure side, given by the pressure and temperature 1 1' 3963.3 p p kPa 1-1 = 2.513 °C 3 is taken from tables and formulas 1001.89 kg m THERMODYNAMIC EFFICIENCY MEASUREMENTS FORMULAS AND SAMPLE CALCULATION 28.02.2014 5 Enclosure 6.1/5 The turbine power is given by 7.814 8.06 W0.9690 G T G PP M The flow is given by 3 68.06 10 = 2.293522.2 1001.89 T T m PQE m s Hydraulic Energy 2 2 1 2 1 2 1 22 p V z V VE p p g z z E E E The Pressure Term 1 1' 1' 1 9.8172 33.02 31.55 1000.923963.3 3977.7 kPa1000 absp p g z z 2 102.3ambp p The total pressure term is 1 2 3977.7 102.3 1000 3871.8 J/kg1000.92 p p pE THERMODYNAMIC EFFICIENCY MEASUREMENTS FORMULAS AND SAMPLE CALCULATION 28.02.2014 6 Enclosure 6.1/6 The Velocity Term According to IEC 60041:1991, chapter 11.2.5.2.2, v2 is taken as zero. 2 2 2 2 1 2 1 2 2 1 2 2 2.29 1 23.8 J/kg2 0.3318 V V V QE A The Potential Term The high and low pressure reference is the same, i.e. the turbine centre, then 0zE Total Hydraulic Energy = 3871.8+23.8= 3895.6 J/kg p V z E E E E 3895.6 396.81m9.8172 n EHg Calculation of Turbine Efficiency 3522.2 100 90.42 %3895.6 m T E E Calculation of Unit Efficiency 90.42 96.83% 87.55 % Tot t Gen THERMODYNAMIC EFFICIENCY MEASUREMENTS UNCERTAINTY ANALYSIS hah 20140228 -1 - Enclosure 6.2/1 Uncertainty analysis 1 ABOUT THE UNCERTAINTY ANALYSIS The uncertainty of a measured value is given in absolute or relative terms. The absolute uncertainty of a measured value X is eX and thus the relative term is X X efX Each component has a systematic and sometimes a random component. The tables given in this analysis indicate which components to be taken into account. The formulas for the systematic and random uncertainties are the same. The systematic uncertainty is denoted X sysf and the random uncertainty is denoted X ranf The uncertainty analysis is performed in spreadsheet at a 95% confidence interval, according to the formulas below. 1.1 Uncertainty in Mechanical Energy Em The uncertainty in mechanical energy is: 2 2 2 2 2 2 10 20 0.52 (3 2)p v zm m E E E E E E EE E m m e e e e e e eefE E 1.1.1 Pressure Term 21/ 2 2 2 2 2 2 11 21 11 21 2 ' ' ' 'p abs abs table Temp abs abs E p p a a e e e a e e p p Uncertainty term Systematic Random epabs11'[kPa] Measuring vessel pressure x x epabs21'[kPa] Outlet pressure x x e z1’' [m] Elevation of pressure transducer x e z11 [m] Elevation of thermometer 1-1 x e z21 [m] Elevation thermometer 2-1 x tableae [dm3/kg] Isothermal factor; due to uncertainty in tabulated values x e a Temp [dm3/kg] Isothermal factor; due to uncertainty in temperature x x THERMODYNAMIC EFFICIENCY MEASUREMENTS UNCERTAINTY ANALYSIS hah 20140228 -2 - Enclosure 6.2/2 1.1.2 Temperature term 21 22 2 2 2 T table Temp E pCp Cp e e e e c Uncertainty term Systematic Random tableCpe [J/kg C]Specific heat capacity; due to uncertainty in tabulated values x TempCpe [J/kg C]Specific heat capacity; due to uncertainty in temperature x x e [°C] Measured temperature difference x x 1.1.3 Velocity term 2 11 21 2 2 11 21vE v v e v e v e Both V1-1 and V2-1 is included in the pressure measurements, so that e E V 0 J / Kg This is true for both the systematic and random part. 1.1.4 Elevation term 2 11 21 2 2 zE z z e e g e g The uncertainty in determining the gravity is neglected. Uncertainty term Systematic Random 11ze [m] Elevation of thermometer 11 x 21ze [m] Elevation of thermometer 21 x THERMODYNAMIC EFFICIENCY MEASUREMENTS UNCERTAINTY ANALYSIS hah 20140228 -3 - Enclosure 6.2/3 1.1.5 Uncertainty in energy distribution The systematic uncertainty due to lack of investigation of the energy distribution of the high-pressure side is taken as (Ref. IEC 41 -1991 ch. 14.7) mEEe%2.010 and at the low pressure side (Ref. IEC 41 -1991 ch. 14.7) mEEe%6.010 The random part of this uncertainty is zero. 1.2 Uncertainty in Hydraulic Energy, E The uncertainty in hydraulic energy is 0.52 2 2 p V Z E E EE E e e eefE E Pressure term 21 22 2 2 2 1' 2' 1' 2'p abs abs E p p abs abs e e e f p p Uncertainty term Systematic Random 1'abspe [kPa] Pressure high pressure side x x 2'abspe [kPa] Pressure low pressure side x x f [%] Density x 1.2.1 Uncertainty in turbine power, flow and velocity term The uncertainty in the measured turbine output is 2 2 2 G G P P f f f The uncertainty in flow is given by THERMODYNAMIC EFFICIENCY MEASUREMENTS UNCERTAINTY ANALYSIS hah 20140228 -4 - Enclosure 6.2/4 1Q P Em e f f where e f The uncertainty in the velocity head term is 21 1 1 vE Q Qe e A Uncertainty term Systematic Random GPf [%] Power measurements x x G f [%] Generator efficiency x Eme [J/kg] Total mechanical energy x x 1.2.2 Potential Term 2 22 1' 2'zE z z e e g e g Uncertainty term Systematic Random 1'ze [m] Elevation of pressure measurement at inlet x 2'ze [m] Elevation of pressure measurement (or tail water level) at outlet x 1.3 Uncertainty in efficiency The uncertainty in the turbine efficiency is 2 2 mE E ef f f