Oahu Wind Integration Study - Hawaii Natural Energy Institute ...

More documents

Recommendations

Info

much smaller in size relative to the wind plant resources evaluated. These smaller, distributed solar PV resources are interconnected to the distribution system whereas the analyses in this study focused exclusively on the transmission system to evaluate system-wide impacts associated with the balancing of generation and load. A comprehensive study of both the distribution and transmission system is required to analyze effectively the system-wide impacts of integrating high levels of solar PV resources on Oahu. Also, note that the historical data necessary to conduct a comprehensive solar integration study for the Oahu system does not exist, and must be developed. In parallel with this effort, the Hawaiian Electric Company performed a number of internal studies to support the “Big Wind” projects. These include studies to improve generating unit capabilities, an assessment of the Energy Management System (EMS), assessments of its load control programs, and on-island transmission infrastructure studies. Other project teams undertook a number of large technical studies centered on the undersea cable system, including undersea topography and routing options, converter system configuration and technology assessments, and project cost estimates. The results presented in this report consider the conclusions and recommendations of many of these studies, where applicable. 1.2. Study Approach Over the past decade, GE Energy Consulting has conducted wind and solar integration studies for electrical systems around North America. Most recently, these include the New England Wind Integration Study and the Western Wind and Solar Integration Study. A summary of the levels of renewable energy studied in each effort is provided in Figure 1-2. The wind integration studies for the islands of Hawaii posed challenges in addition to those associated with integrating high levels of wind power because of the unique characteristics of island electrical systems. The frequency of a North American power system will be maintained at exactly 60 Hz if the supply of and demand for electricity is perfectly matched in a region. If imbalanced, the frequency will begin to deviate from 60 Hz. Even without the integration of these renewable resources, frequency on an island electrical system tends to vary more than large electrical systems because the system is not interconnected with other power systems. With no electrical interconnection to neighboring systems, each island must manage its system frequency independently. To maintain adequate system performance during unexpected grid events, the spinning reserve requirement for the island of Oahu is 180 MW. This means that at least 180MW of power can be made available from the units already on-line (by increasing the production from these units) should an event take place. This provides sufficient power should the largest plant, AES, unexpectedly disconnects from the system. 6
Figure 1-2. Renewable Integration Studies conducted by GE Another characteristic of an island system is the significance that each generating unit can have on overall system performance. Therefore, characteristics of the Oahu electrical system dictate the design criteria of the generating units. For example, it is common to see generating plants in North America in the 1000 MW size or larger, to leverage the economies of scale. This is possible because the size of the electrical system does not generally impose design constraints on generating units. In the western region of the continental United States, referred to as the Western Electricity Coordinating Council (WECC), the peak load is greater than 150,000 MW. This peak load is more than 100 times larger than the Oahu power system. The loss of a 1000 MW unit in the WECC region is a small percentage of this region’s generation and has a small effect on the system frequency deviation. Now consider the Oahu system, where the single largest unit is the AES coal plant, rated at 180 MW. This single unit provides anywhere from 15 to 30% of the Oahu system load, and typically is the reason for system operating policies and maintenance scheduling. These unique system characteristics made it necessary to capture accurately, 1) the dynamic capabilities of each generating unit, 2) the unique operational characteristics of the system, and 3) performance of automatic generation controls (AGC), the controller that schedules and dispatches each unit to maintain system stability from seconds to minutes to hour timeframe. The Oahu Wind Integration Study was conducted in two phases. In Phase 1, the system models were developed and simulation results were validated against historical data from 2007, for both production cost and dynamic simulations. In Phase 2, different wind energy scenarios were constructed and system operation was simulated for the study year. These scenarios included different configurations of wind resources (as listed in Table 1-1) and simulations of various strategies to; 1) increase wind energy delivered to the system, 2) reduce system operating cost, or 3) improve system reliability. The initial scenario analysis (Scenario 5) was quite extensive, requiring multiple iterations of production cost simulations, analyses of results, and modifications to assumptions to ensure reasonable operation of the system. Once production cost modeling results were deemed reasonable, dynamic modeling tools were used to identify hours of the year to simulate contingency events and conduct analyses of the impact of wind variability and uncertainty on the system. 7
Page 1 and 2: Oahu Wind Integration Study Final R
Page 3 and 4: 1.0 Executive Summary Hawaii is an
Page 5: Oahu 100MW Wind 100MW PV Lanai 200M
Page 9 and 10: educe its output, while remaining i
Page 11 and 12: Figure 1-6. Share of annual energy
Page 13 and 14: Figure 1-8. Total annual variable c
Page 15 and 16: extreme downward variability over t
Page 17 and 18: 1.6. Short-timescale wind variabili
Page 19 and 20: Figure 1-11. Frequency performance
Page 21 and 22: down-reserve requirement. Alternati
Page 23 and 24: capability, the remaining 163 MW of
Page 25 and 26: o Table 1-2 showed that nearly 95%
Page 27 and 28: 1.8.2. Thermal Unit Modifications
Page 29 and 30: 6.3.1. Overview of the GE MAPS TM B
Page 31 and 32: 10.5.3. Down-reserve...............
Page 33 and 34: Figure 6-13. Baseline 2014 scenario
Page 35 and 36: tripped off-island wind plant carry
Page 37 and 38: Table 8-10. Summary of short-term a
Page 39 and 40: 2.0 Acknowledgements Our team would
Page 41 and 42: are presented in this section for S
Page 43 and 44: 4.1. Study objectives The General E
Page 45 and 46: human decision-making play a substa
Page 47 and 48: Voltage Governor Support Response P
Page 49 and 50: maneuvering that may be a result of
Page 51 and 52: hours of operation that warrant fur
Page 53 and 54: and maintenance costs) based on ass
Page 55 and 56: Another factor for consideration is
Page 57 and 58:
Figure 5-3 GE MAPS TM model results
Page 59 and 60:
models of all of HECO-owned and IPP
Page 61 and 62:
Table 5-4 Proposed thermal unit gov
Page 63 and 64:
Table 5-6 Summary of various dynami
Page 65 and 66:
Table 5-8. Dynamic Database - Excit
Page 67 and 68:
o 50 MW Oahu2: Modeled as a 50 MW g
Page 69 and 70:
400 MW Off-island Oahu Wind Plant M
Page 71 and 72:
turbine/governor systems in the dyn
Page 73 and 74:
Pulsating logic: o All units under
Page 75 and 76:
Hz 60.8 60.6 60.4 60.2 60 Frequency
Page 77 and 78:
modeled as a single CT/ST and is ba
Page 79 and 80:
6.2.1. Development of Wind and Sola
Page 81 and 82:
Estimated power curve P farm = 30MW
Page 83 and 84:
Figure 6-3 The largest 1 minute win
Page 85 and 86:
Figure 6-5. Histogram of wind power
Page 87 and 88:
At the request of the evaluation te
Page 89 and 90:
6.2.5. Reserve requirements The Oah
Page 91 and 92:
Figure 6-10. Thermal unit heat rate
Page 93 and 94:
6.3.1.5.2. AES coal-fired steam pla
Page 95 and 96:
Figure 6-12. Baseline 2014 scenario
Page 97 and 98:
Methods to forecast solar power wer
Page 99 and 100:
1. No forecast of wind and solar (S
Page 101 and 102:
Table 6-3. Scenario 5: Wind and sol
Page 103 and 104:
Figure 6-18. Scenario 5. Fuel energ
Page 105 and 106:
Table 6-4. Scenario 3: Wind and sol
Page 107 and 108:
6.7. Conclusions As the wind energy
Page 109 and 110:
Figure 6-21. Scenario 3. Fuel energ
Page 111 and 112:
The results of the scenario analysi
Page 113 and 114:
Reduce On-line Regulating Reserves
Page 115 and 116:
energy is accepted, these units are
Page 117 and 118:
Figure 7-3. Scenario 5C: Fuel energ
Page 119 and 120:
Sce nario 5C Scenario 5F1 40MW down
Page 121 and 122:
Scenario 5F1 Scenario 5F2 Seasonal
Page 123 and 124:
7.4.1. Sensitivity to Solar Forecas
Page 125 and 126:
on the time of day and the load lev
Page 127 and 128:
Figure 7-15. Scenario 5F3. Number o
Page 129 and 130:
Figure 7-18. Renewable energy deliv
Page 131 and 132:
more expensive cycling energy displ
Page 133 and 134:
Figure 7-23. Delivered wind energy
Page 135 and 136:
18-weeks during the year was includ
Page 137 and 138:
should be noted that the effective
Page 139 and 140:
Note that the average heat rate for
Page 141 and 142:
The heat rate by unit type is shown
Page 143 and 144:
The capacity factors of the renewab
Page 145 and 146:
On the other hand, short-term analy
Page 147 and 148:
Table 8-2. Long term screening resu
Page 149 and 150:
Figure 8-4. Drop in wind and solar
Page 151 and 152:
emain flat in their generation for
Page 153 and 154:
Hz Hz 60.2 60 Frequency AGC Mode 59
Page 155 and 156:
Figure 8-9. Long-term analysis for
Page 157 and 158:
The up-range adequacy of the system
Page 159 and 160:
The short-term screening results fo
Page 161 and 162:
MW 120 100 80 60 40 20 0 0 600 200M
Page 163 and 164:
Hz Hz 60.2 60 59.8 59.6 59.4 0 600
Page 165 and 166:
events., which will be described la
Page 167 and 168:
Figure 8-18. Down-range10 at the be
Page 169 and 170:
o Frequency performance (Section 8.
Page 171 and 172:
MW 450 400 350 300 250 200 Scenario
Page 173 and 174:
8.5.3. Results Using the volatile w
Page 175 and 176:
MW 80 60 40 K2 K3 K4 K5 K6 MW 100 2
Page 177 and 178:
Figure 8-30 shows that the maneuver
Page 179 and 180:
• The load flow model in GE PSLF
Page 181 and 182:
Frequency RMS (Hz) 0.035 0.03 0.025
Page 183 and 184:
Intermediate Farm power 1 1+ sT + _
Page 185 and 186:
In step 2 above, the 0.1% percentil
Page 187 and 188:
1 / 120 per unit Ramp Rate Power (M
Page 189 and 190:
MW 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0
Page 191 and 192:
MW MW 1.800 1.600 1.400 1.200 1.000
Page 193 and 194:
Under the scenarios considered in t
Page 195 and 196:
- No response (base case) - Moderat
Page 197 and 198:
Hz MW 62 61.5 61 60.5 System freque
Page 199 and 200:
esulted in noticeable improvements
Page 201 and 202:
In both scenarios none of the 200 M
Page 203 and 204:
Figure 8-49: Transient simulation r
Page 205 and 206:
Figure 8-52: Transient simulation r
Page 207 and 208:
o Wind turbine inertial response tr
Page 209 and 210:
o Reducing the on-line regulating r
Page 211 and 212:
9.2.5.3. Wind Plant Ramp Rate Limit
Page 213 and 214:
o Given the high power rating of th
Page 215 and 216:
power, thereby contributing to the
Page 217 and 218:
10.1.5. Recommend that HECO evaluat
Page 219 and 220:
10.2.2. Recommend solar plants to p
Page 221 and 222:
o This recommendation assumes that
Page 223 and 224:
acking down thermal units. In Scena
Page 225 and 226:
o In Scenario 5F3 and 5F2 the regul
Page 227 and 228:
10.5.5. Additional Operator Informa
Page 229:
simultaneous occurrence of the larg
show all

Oahu Wind Integration Study - Hawaii Natural Energy Institute ...

Create successful ePaper yourself

Delete template?

Save as template?