View
37
Download
0
Category
Preview:
DESCRIPTION
ISO-NE New England Load Forecast Presentation. NEPOOL Power Supply Planning Committee Current Installed Capacity Requirement/Required Reserves Calculation Methodology Workshop November 18, 2004 David Ehrlich ISO New England. Agenda. Actual and Weather Normalized Peaks - PowerPoint PPT Presentation
Citation preview
ISO-NE New EnglandLoad Forecast Presentation
NEPOOL Power Supply Planning Committee
Current Installed Capacity Requirement/Required Reserves Calculation
Methodology Workshop
November 18, 2004
David Ehrlich
ISO New England
2
Agenda
• Actual and Weather Normalized Peaks
• ISO-NE Short-run Energy and Peak Forecast Methodology
• Forecast a Seasonal Peak Load Distribution– Based on Historical Weather Distributions– The 50/50 – Reference Case – Most Likely– Do Not Forecast the Actual Peak Day
• Summer Weather and Peak Load Distributions
• 2004 Weather Normal Summer Peak
• 4/04 CELT Summer Peak Load Distributions
3
More Complete Documentation of ISO-NE Energy and
Peak Load Models and April 2004 CELT and RTEP04
Forecasts can be Found on the ISO-NE Website :
http://www.iso-ne.com/Historical_Data/forecast/
4
ISO-NE New England Summer PeaksActual and Weather Normal
14000
16000
18000
20000
22000
24000
26000
1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004
Years
MW
Actual Weather Normal
5
WTHI and Temperature at Time of ISO-NE Summer PeakSummer Peak Expected to Occur at 80.1
74
76
78
80
82
84
86
88
90
92
94
96
1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004
Years
Weig
hte
d T
em
pera
ture
/Hu
mid
ity In
dex
& T
em
pr.
WTHI 80.1 Temperature 90
6
ISO-NE Econometric Model of Quarterly Energy
Aggregate Quarterly to Annual
Energy = Number of Households * Energy per Household
Energy per Household =
Constant + DummyQ2 + DummyQ3 + DummyQ4 +
Coeff * Heating Degree Days +
Coeff * Cooling Degree Days +
Coeff * Real price of Electricity +
Coeff * Real Income per Household
7
Coefficients: ISO-NE Short-run Quarterly Energy Model
Real Income per Household 0.036297Real Price of Electricity -0.051287Heating Degree Days 0.000493Cooling Degree Days 0.002673Dummy Quarter 2 0.353658Dummy Quarter 3 0.674909Dummy Quarter 4 0.184243Constant 1.958934R Square 0.91
8
ISO-NE Econometric Model of Short-run Peak Load (Cooling Season May-Sep)
Typical Daily Peak by Month ( 1992-2004 Non-holiday Weekday Daily Peaks)
Create Weekly Distributions by Using Historical Weekly WTHI Distributions
Daily Peak =
Constant + Monday + Friday +
Coeff * CLI * (WTHI-55)**2 +
Coeff * CBLI * Base Year Energy
CLI: Cooling Load Index CBLI: Cooling Base Load IndexHistorical Weekly WTHI Distributions based on 37 Years (1963-1999)WTHI: Three Day Weighted Temperature/Humidity IndexTHI: .5*Temperature + .3*DewPoint + 15Weights: .59*Current + .29*Lag1 + .12*Lag2
9
Coefficients : ISO-NE Econometric Model of Short-run Peak Load
May June July August September
Energy 1.64 1.62 1.53 1.61 1.71WTHI 5.81 7.85 8.66 8.65 6.60Monday 79.71 42.99 145.82 26.14 34.27Friday -38.62 -117.99 -0.75 -197.66 -157.12Constant -377.40 -170.00 423.27 -83.92 -656.63R Square 0.92 0.95 0.94 0.97 0.93
10
Cooling Load Index Comparison: ISO-NECoefficients of Annual Regression of Summer Daily Peaks and WTHI
1.0
1.2
1.4
1.6
1.8
2.0
1992 1994 1996 1998 2000 2002 2004 2006
In
dexed
to
1992
Trend:4/05 Trend:4/04 Actual:4/04 Actual:4/05
11
Cooling Base Load Index Comparison: ISO-NEConstants of Annual Regression of Summer Daily Peaks and WTHI
0.95
1.00
1.05
1.10
1.15
1.20
1992 1994 1996 1998 2000 2002 2004 2006
In
dexed
to
1992
Trend:4/05 Trend:4/04 Actual:4/04 Actual:4/05
12
ISO-NE Summer Peak Load FactorsA Measure of Energy to Seasonal Peak or "Peakiness"
55
57
59
61
63
65
67
69
71
1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004
Years
Lo
ad
Facto
rs
Actual Weather Normal
13
SECTION I.8 - SummariesSeasonal Peak Load Forecast Distributions for
Peak Load Forecast at Milder Than Expected Peak Load Forecast at More Extreme Than Expected Weather
Summer (MW)2004 24660 24875 25080 25415 25735 26045 26315 26755 27305 277552005 25190 25415 25625 25970 26305 26625 26905 27365 27935 284002006 25445 25670 25885 26235 26570 26895 27180 27640 28220 286902007 25680 25910 26120 26475 26815 27145 27430 27900 28485 289602008 25940 26170 26385 26740 27085 27415 27705 28180 28770 292552009 26230 26465 26680 27045 27390 27725 28015 28495 29090 295802010 26565 26800 27025 27390 27740 28080 28375 28860 29460 299552011 26975 27220 27440 27815 28170 28515 28815 29305 29915 304102012 27340 27585 27810 28190 28550 28900 29200 29700 30315 308202013 27655 27905 28135 28515 28880 29235 29540 30045 30660 31170
WTHI (1) 78.8 79 79.3 79.7 80.1 80.5 80.8 81.4 82 82.5
Dry-Bulb Temperature (2) 88.5 88.9 89.2 89.9 90.4 91.2 92.2 92.9 94.2 95.4
Probability of Forecast Being 90% 80% 70% 60% 50% 40% 30% 20% 10% 5%
Winter (MW)2004/05 21820 21960 22045 22160 22370 22545 22725 22880 23255 236102005/06 22065 22200 22290 22405 22615 22795 22975 23135 23510 238652006/07 22290 22430 22515 22630 22845 23030 23210 23370 23750 241102007/08 22540 22685 22770 22890 23105 23290 23475 23635 24020 243852008/09 22810 22955 23045 23160 23380 23570 23750 23920 24310 246752009/10 23100 23250 23340 23460 23680 23870 24060 24225 24620 249902010/11 23455 23600 23695 23815 24040 24230 24425 24595 24985 253602011/12 23845 23995 24090 24210 24440 24635 24830 25000 25400 257802012/13 24120 24270 24365 24490 24720 24920 25115 25290 25690 260702013/14 24370 24525 24620 24745 24980 25180 25380 25555 25960 26350
Dry-Bulb Temperature (3) 10.8 9.7 9.1 8.3 6.8 5.6 4.4 3.3 0.9 -1.3
The tables above show the distributions around the seasonal reference peak load forecast (50%). The distributions are based on historical weather data with the reference case as the most likely or expected weather of 80.1 New England WTHI in the summer and 6.8 New England dry-bulb temperature in the winter. The 2003 actual summer peak load of 24685 MW occurred at a New England WTHI of 79.5 and dry-bulb temperature of 89.5.
FOOTNOTES:
(1) WTHI - A 3-DAY WEIGHTED TEMPERATURE-HUMIDITY INDEX FOR 8 NEW ENGLAND WEATHER STATIONS. FOR MORE INFORMATION ON THE WEATHER VARIABLES SEE http:/www.iso-ne.com/historical_data/daily_monthly/summary_definitions.html.
(2) DRY-BULB TEMPERATURE SHOWN IN THE SUMMER SEASON ARE FOR INFORMATIONAL PURPOSES ONLY. WTHI IS THE WEATHER VARIABLE USED IN PRODUCING THE SUMMER PEAK LOAD FORECAST.
(3) DRY-BULB TEMPERATURE IS A WEIGHTED VALUE FROM 8 NEW ENGLAND WEATHER STATIONS.
NEPOOL CELT REPORT - APRIL 2004
ReferenceForecast atExpectedWeather
14
ISO-NE 2004 Summer WTHI at Time of Daily Peak LoadsJune - August Non Holiday Weekdays
66
68
70
72
74
76
78
80
82
JU
N:8
J
UN
:9
JU
N:1
0
JU
N:1
5
JU
N:1
6
JU
N:1
7
JU
N:1
8
JU
N:2
3
JU
N:2
4
JU
N:2
5
JU
N:3
0
JU
L:1
J
UL:2
J
UL:6
J
UL:7
J
UL:8
J
UL:9
J
UL:1
2
JU
L:1
4
JU
L:1
5
JU
L:1
6
JU
L:1
9
JU
L:2
0
JU
L:2
1
JU
L:2
2
JU
L:2
3
JU
L:2
6
JU
L:2
9
JU
L:3
0
AU
G:2
A
UG
:3
AU
G:4
A
UG
:5
AU
G:9
A
UG
:10
AU
G:1
1
AU
G:1
2
AU
G:1
3
AU
G:1
7
AU
G:1
8
AU
G:1
9
AU
G:2
0
AU
G:2
3
AU
G:2
5
AU
G:2
6
AU
G:2
7
AU
G:3
0
AU
G:3
1
Non Holiday Weekdays
WT
HI
Actual WTHI WTHI Peak Expected to Occur at (80.1)
15
ISO-NE 2004 Summer Actual & Weather Adjusted Daily Peak LoadsJune - August Non Holiday Weekdays
17000
18000
19000
20000
21000
22000
23000
24000
25000
26000
27000
JU
N:8
J
UN
:9
JU
N:1
0
JU
N:1
5
JU
N:1
6
JU
N:1
7
JU
N:1
8
JU
N:2
3
JU
N:2
4
JU
N:2
5
JU
N:3
0
JU
L:1
J
UL:2
J
UL:6
J
UL:7
J
UL:8
J
UL:9
J
UL:1
2
JU
L:1
4
JU
L:1
5
JU
L:1
6
JU
L:1
9
JU
L:2
0
JU
L:2
1
JU
L:2
2
JU
L:2
3
JU
L:2
6
JU
L:2
9
JU
L:3
0
AU
G:2
A
UG
:3
AU
G:4
A
UG
:5
AU
G:9
A
UG
:10
AU
G:1
1
AU
G:1
2
AU
G:1
3
AU
G:1
7
AU
G:1
8
AU
G:1
9
AU
G:2
0
AU
G:2
3
AU
G:2
5
AU
G:2
6
AU
G:2
7
AU
G:3
0
AU
G:3
1
Non Holiday Weekdays
MW
Actual Peak Weather Adjusted Peak WeatherNormal 25770
16
ISO-NE Distribution of 2004 Summer Weather Adjusted Daily PeaksMedian & Upper/Lower Bounds versus Weather Normal Summer Peak
24500
25000
25500
26000
26500
27000
1 5 9 13 17 21 25 29 33 37 41 45
June-August Non Holiday Weekdays (Sorted Low to High)
MW
Weather Adjusted Daily Median 25810 Upper Bound 26055
Low er Bound 25565 Weather Normal 25770
17
WTHI at Time of ISO-NE Summer Peak - SortedSummer Peak Expected to Occur at 80.1
75
76
77
78
79
80
81
82
83
84
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35
Years
Weig
hte
d T
em
pera
ture
/Hu
mid
ity In
dex
WTHI 80.1
18
ISO-NE New England Extreme Weather Distribution : Week 30 A Three Day Weighted Temperatur-Humidity Index
78
79
80
81
82
83
84
85
1 11 21 31 41 51 61 71 81 91
WT
HI
WTHI 50/50 90/10
19
Extreme Weather Based Distribution of Daily Peak Loads ISO-NE New England Week 30 of 2004 (April 2004 CELT)
24000
25000
26000
27000
28000
29000
30000
1 11 21 31 41 51 61 71 81 91
MW
Load 50/50 (25735MW) 90/10 (27305MW)
20
ISO-NE New England Summer Peak Forecast ErrorOne Year Ahead Forecast / Average Error Under 1%
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
Year Forecast Was Done
Perc
en
t E
rro
r
21
ISO-NE 2001 Summer Peak Forecast Distributionand Actual Peak
2365023840
23980
24390
2475024967
25180
22500
23000
23500
24000
24500
25000
25500
90.450/50
91.2 92.2 92.9 94.290/10
95.2Actual
95.4
Temperature
MW
22
ISO-NE 2003/2004 Winter Peak Forecast Distributionand Actual Peak
22010
22190
2237022520
2290022817
23250
21500
22000
22500
23000
23500
6.8 50/50
5.6 4.4 3.3 0.9 90/10
-0.7 Actual
-1.3
Temperature
MW
23
Weather Distribution Where the 50/50 Seasonal Peak OccursWinter:Temperature Summer:Temperature/Humidity
1
11
21
31
41
51
61
71
81
1 5 9 13 17 21 25 29 33 37 41 45 49
Weeks in Year
WT
HI / T
em
pr
NEW ENGLAND SOUTHERN NORTHERN
24
MEANS OF DAILY PEAK ISO-NE Weather DISTRIBUTIONSWTHI for Cooling / Temperatrure for Heating
24
34
44
54
64
74
1 5 9 13 17 21 25 29 33 37 41 45 49
Weeks of Year
WT
HI
1963-1999 1964-2000 1965-2001 1982-2001 1992-2001
25
50/50 Weekly Peak ISO-NE Weather DistributionsWTHI for Cooling / Temperature for Heating
0
10
20
30
40
50
60
70
80
90
1 5 9 13 17 21 25 29 33 37 41 45 49
Weeks of Year
WTHI
1963-1999 1964-2000 1965-2001 1982-2001 1992-2001
26
Means : 4/04 ISO-NE 2004 Weekly Peak Load Distributions
16000
18000
20000
22000
Weeks
MW
27
Standard Devations : 4/04 ISO-NE 2004 Weekly Peak Load Distributions
0
600
1200
1800
2400
Weeks
MW
28
4/04 ISO-NE 2004 Weekly Peak Load DistributionsThe 10/90, 50/50, and 90/10 Seasonal Peak Deciles
16000
18000
20000
22000
24000
26000
28000
10/90 50/50 90/10
29
Skewness : 4/04 ISO-NE 2004 Weekly Peak Load Distributions
-1.0
0.0
1.0
2.0
3.0
Weeks
30
3rd Cumulants : 4/04 ISO-NE 2004 Weekly Peak Load Distributions
0
1000000000
2000000000
3000000000
4000000000
5000000000
6000000000
7000000000
8000000000
Weeks
31
ISO-NE New England Hourly Loads : 1995 and 2002As Percent of Annual Peak
30
40
50
60
70
80
90
100
110
Hours in Year
Perc
en
t o
f P
eak
1995 2002
32
Questions ?
Recommended