Distributed Renewable Generation Profiling Methodology ERCOT Load Profiling March 4, 2008

Distributed Renewable GenerationProfiling Methodology

ERCOT Load ProfilingMarch 4, 2008

2

Distributed Renewable Generation (DRG)

TDSPs responded to ERCOT’s request for information on premises that have DRG with a generation capacity < 50 kW.

What is out there?

Five of the ESI IDs included above have PV and wind generation. This means there are currently 87 unique ESI IDs known to have one or more type of DRG (< 50 kW).

1. Photovoltaic (PV)A. Residential (RES) 52B. Business (BUS) 6

2. WindA. RES 30B. BUS 4

3. Other

58 ESI IDs

34 ESI IDs

0 ESI IDs

3

DRG Sites – Available Information

Even though TDSPs provided the best information available there are many barriers to analyzing DRG sites. For example:

Given the above, it is difficult to identify the effects of DRG from the available meter read data.

• An interconnection agreement date is not necessarily meaningful. DRG may have been operating for years before agreement is signed, or may not operate until well after agreement is completed.

• Sometimes inverter capacity is known—but generator capacity is not known.

• Presently, energy exported to the Distribution System (energy outflow from the premise) is only available for a handful of ESI IDs.

4

Residential DRG – Photovoltaic (PV)

Generation Capacity for 52 ESI IDs

0

1

2

3

4

5

6

7

8

9

10

11

ESI IDs 1 thru 52

kW

mean = 3.5

5

Residential PV

Total 2007 kWh 'Inflow to Premise' for 51 ESI IDs

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

50,000

ESI IDs 1 thru 51

kW

h

mean = 13,668

Note: The usage for an ESI ID that used 200,000 kWh was excluded from this chart.

6

Residential PV

Due to potential confidentiality issues, a chart displaying both DRG capacity (kW) and annual usage (kWh) is not presented here.

However, the correlation of the two variables is 0.217 (excluding the outlier).

The table of ESI ID counts below may help illustrate the relationship. Each respective variable’s median value serves as the break between high and low.

Low kWh High kWhLow kW Low kW

17 9

Low kWh High kWhHigh kW High kW

9 17

7

Business PV


0

5

10

15

20

25

30

35

40

45

50

ESI IDs 1 thru 6

kW

mean = 8.9

8

Business PV


0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

ESI IDs 1 thru 6

kW

h

mean = 149,624

9

Residential DRG – Wind


0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

30

32

ESI IDs 1 thru 30

kW

mean = 5.6

10

Residential Wind


0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

50,000

55,000

ESI IDs 1 thru 30

kW

h

mean = 19,081

11

Residential Wind

For wind ESI IDs the correlation of DRG capacity and annual usage is 0.153.

The following table of ESI ID counts uses each respective variable’s median value as the break between high and low. Values equal to the median were treated as low.

Low kWh High kWhLow kW Low kW

12 3

Low kWh High kWhHigh kW High kW

7 8

12

Business Wind


0

2

4

6

8

10

12

ESI IDs 1 thru 4

kW

mean = 3.9

13

Business Wind


0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

ESI IDs 1 thru 4

kW

h

mean = 5,284

14

PV Generation

How much energy will a PV array produce?

Given the currently known average Residential PV generation capacity of 3.5 kW (AC), at 100% capacity factor there would be (3.5 * 24 =) 84 kWh generated per day.

If we utilize the Interstate Renewable Energy Council’s irradiance estimate of 20% from its presentation to the DGTF on 12/04/07, the estimated yield would be 16.8 kWh per day.

Applying the above to the average Business PV generation capacity of 8.9 kW (AC) yields an estimated 42.7 kWh per day.

For simplicity, the energy produced by a PV array is presented in most of the slides as a sine wave spanning 9:00 AM to 5:00 PM.

15

Residential PV

Prospective PV Generation Shape

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

7:00

7:30

8:00

8:30

9:00

9:30

10:0

010

:30

11:0

011

:30

12:0

012

:30

13:0

013

:30

14:0

014

:30

15:0

015

:30

16:0

016

:30

17:0

017

:30

18:0

018

:30

19:0

019

:30

ending time

kWh

16

Residential PV – Building the Profile

How would a daily PV load profile be derived?

To build a PV profile (consistent with what has come to be known as ‘Option 5’) for a specific profile type and weather zone, e.g., for PV ESI ID that is currently assigned RESHIWR NCENT:

This PV profile can then be used in the Data Aggregation process.

The kWh ‘outflow to the grid’ would be applied in settlement evenly across all days, spanning the intervals from 11:00 AM to 3:00 PM.

1. For a specific day, take the current RESHIWR NCENT profile;

2. Multiply each value by 0.89 to scale it to the average PV ESI ID (more info in Appendix A);

3. Scale it such that when the PV generation shape is applied in the next step the kWh will remain the same;

4. Subtract the values of the PV generation shape to produce the RESHIPV NCENT load profile.

17


0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

1. RESHIWR NCENT load profile from new models

1. RESHIWR NCENT load profile for 08/26/07

(59.58 kWh)

18


0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

2. Scale RESHIWR NCENT to the average PV ESI ID

2. RESHIWR NCENT load profile for 08/26/07, scaled

to average PV ESI ID (50.02 kWh)

1. RESHIWR NCENT load profile for 08/26/07

(59.58 kWh)

19


0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

3. Scale up so that PV gen shape can be subtracted

3. RESHIWR NCENT load profile for 08/26/07, scaled to

average PV ESI ID, then scaled for PV output

(66.82 kWh)

2. RESHIWR NCENT load profile for 08/26/07, scaled


20


0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

4. RESHIPV NCENT load profile for 08/26/07

(50.02 kWh)

4. Subtract the PV gen shape to produce RESHIPV NCENT

3. RESHIWR NCENT load profile for 08/26/07, scaled to


(66.82 kWh)

21

Residential PV – Applying the Profile

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h


(50.02 kWh)

Suppose...

ESI ID's meter read for Aug. 1-31:kWh load (inflow to premise): 2,266 kWh gen (outflow to grid): 82

RESHIPV NCENT for Aug. 1-31: 1,424.71 kWh

2,266 / 1,424.71 = 1.59

RESHIPV NCENT and ESI ID's Meter Read

22


0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h


(50.02 kWh)

Suppose...

ESI ID's meter read for Aug. 1-31:kWh load: 2,266 kWh gen: 82


2,266 / 1,424.71 = 1.59

RESHIPV NCENT load profile for 08/26/07

scaled to this ESI ID's kWh load

(79.55 kWh)

RESHIPV NCENT applied to an ESI ID

23


-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

Suppose...



2,266 / 1,424.71 = 1.59



(79.55 kWh)

RESHIPV NCENT applied to a PV ESI ID and kWh 'Outflow to Grid'

2.73 kWhkWh gen (82 kWh / 30)

24


In the preceding slide the ESI ID’s usage was higher than that of the PV profile.

What if an ESI ID had significantly lower usage?

25


-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

Suppose...

ESI ID's meter read for Aug. 1-31:kWh load: 627 kWh gen: 88


627 / 1,424.71 = 0.6



(22.01 kWh)

RESHIPV NCENT applied to a PV ESI ID and kWh 'Outflow to Grid'

kWh gen (88 kWh / 30) 2.93 kWh

26

Business PV – Building the Profile

0

1

2

3

4

5

6

7

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

1. BUSLOLF NCENT load profile from new models

1. BUSLOLF NCENT load profile for 08/26/07

(158.26 kWh)

27


0

1

2

3

4

5

6

7

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

2. Scale BUSLOLF NCENT to the average PV ESI ID

2. BUSLOLF NCENT load profile for 08/26/07, scaled


1. BUSLOLF NCENT load profile for 08/26/07

(158.26 kWh)

28


0

1

2

3

4

5

6

7

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

3. Scale up so that PV gen shape can be subtracted

3. BUSLOLF NCENT load profile for 08/26/07, scaled to


(437.32 kWh)

2. BUSLOLF NCENT load profile for 08/26/07, scaled


29


0

1

2

3

4

5

6

7

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

4. Subtract the PV gen shape to produce BUSLOPV NCENT

4. BUSLOPV NCENT load profile for 08/26/07

(394.60 kWh)

3. BUSLOLF NCENT load profile for 08/26/07, scaled to


(437.32 kWh)

30

Business PV – Applying the Profile

0

1

2

3

4

5

6

7

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

Suppose...


BUSLOPV NCENT for Aug. 1-31: 18,036.17 kWh

3,408 / 18,036.17 = 0.19

BUSLOPV NCENT and ESI ID's Meter Read

4. BUSLOPV NCENT load profile for 08/26/07

(394.60 kWh)

31


0

1

2

3

4

5

6

7

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

Suppose...



3,408 / 18,036.17 = 0.19

BUSLOPV NCENT applied to an ESI ID

BUSLOPV NCENT load profile for 08/26/07

scaled to this ESI ID's 'inflow to premise'

(74.56 kWh)

32


0

5

10

15

20

25

30

35

40

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

Suppose...

ESI ID's meter read for Aug. 1-31:kWh load: 104,321 kWh gen: 1,652


104,321 / 18,036.17 = 5.78

BUSLOPV NCENT applied to an ESI ID

BUSLOPV NCENT load profile for 08/26/07

scaled to this ESI ID's 'inflow to premise'

(2,280.77 kWh)

33

PV Model Building

Following are some additional details planned for inclusion in the load profile models for PV ESI IDs. The examples shown are for Residential, but the same methodology would be applied to Business as well.

34

• Residential PV Generation assumptions– Represented using Sine function– Begin/End Times for PV Generation are day of year & weather zone

specific• 1 hour after sunrise • 1 hour before sunset

– Daily kWh Generation is based on 3.5 kW with a 20% capacity factor

• Average daily PV Generation is 16.8 kWh • Average daily PV produces output for 10.2 hours (range: 7.9 – 12.4) • Daily PV Generation is prorated based on hours of generation for the

day compared to an average dayExample day with 8 hours of Generation:

2.138.162.10

8PVGenkWh

Residential PV – Building the Model

35

• Residential PV Model assumptions–Standard Profile multiplied by 1.17

Where:Average PV premise Daily kWh = 69.83 (adjusted for PV Gen) Average Standard Profile Daily kWh = 59.58

– Subtract PV Generation from scaled up Profile– if result in an interval is negative, set to zero

• Beta test MetrixND Project file has been developed for Reshiwr_North – Results for 2005 shown graphically on the next 3 slides

17.158.59

83.69tiplierProfileMul

Residential PV – Building the Model

36

PV Gen PV Profile Standard Profile

Jan 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh

Mar 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kW

h

Apr 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kW

h

Feb 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh

Residential HIWR North PV

37


May 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh

Jun 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh

Jul 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh

Aug 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh


38


Sep 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh

Oct 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh

Nov 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93

Interval

kWh

Dec 15, 2005

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93Interval

kWh


39

Wind – Building the Profile

How would a daily wind load profile be derived for Residential and Business?

At this point it appears that energy from distributed wind generation would be spread evenly across all hours. Though a ‘wind’ profile type assignment would still be needed to address kWh outflow to the distribution system, the standard profile for the respective profile type (but renamed) would still be used in settlement.

Wind-generated ‘outflow to the grid’ would likely be spread evenly to all hours in settlement, as well.

40

Residential Wind – Applying the Profile

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

12:1

5 AM

1:00

AM

1:45

AM

2:30

AM

3:15

AM

4:00

AM

4:45

AM

5:30

AM

6:15

AM

7:00

AM

7:45

AM

8:30

AM

9:15

AM

10:0

0 AM

10:4

5 AM

11:3

0 AM

12:1

5 PM

1:00

PM

1:45

PM

2:30

PM

3:15

PM

4:00

PM

4:45

PM

5:30

PM

6:15

PM

7:00

PM

7:45

PM

8:30

PM

9:15

PM

10:0

0 PM

10:4

5 PM

11:3

0 PM

ending time

kW

h

Suppose...

ESI ID's meter read for Aug. 1-31:kWh 'inflow to premise': 2,579 kWh 'outflow to grid': 47

RESHIWD NCENT for Aug. 1-31: 1,424.71 kWh

2,579 / 1,424.71 = 1.81

RESHIWD NCENT load profile for 08/26/07 scaled

to this ESI ID's usage (107.84 kWh)

RESHIWD NCENT ESI ID and kWh 'Outflow to Grid'

kWh gen (47 kWh / 30) 1.63 kWh

RESHIWD NCENT load profile for 08/26/07

(59.58 kWh)

41

DRG

Questions or comments?

42

Appendix A – Profile Scalar

Scalar for the ‘standard’ load profile:

Slide 5 shows the average kWh ‘inflow to premise’ to be 13,668 for 2007.

The profile type and weather zone combination that had the most reported PV generation was RESHIWR NCENT. That combination’s kWh for all of 2007 from the new profile models was 16,281.

The ratio of these two values is approximately 0.84. Using this value as a scalar in the first step of building a PV load profile serves two purposes:

1. It maintains a proportional PV output as the ESI ID’s kWh ‘inflow to premise’ varies; and

2. It prevents the PV load profile value from going negative.

43

Appendix A – Profile Scalar

Scalar for the ‘standard’ load profile:

Slide 5 shows the average kWh ‘inflow to premise’ to be 13,668 for 2007.

To determine the scalar for the standard load profile, the following ratio was calculated for each Residential PV ESI ID:

kWh load for 2007 / 2007 kWh for respective profile type & weather zone

The average of the 51 ratios (excluding the outlier) is approximately 0.89. Using this value as a scalar in the first step of building a PV load profile serves two purposes:

1. It maintains a proportional PV output as the ESI ID’s kWh ‘inflow to premise’ varies; and

2. It prevents the PV load profile value from going negative.

44

Appendix B – Insolation Across Texas

Source: InfinitePower.org

45

Appendix C – Sunrise Times

Summer Solstice and Winter Solstice -- 2007

6:00 AM 6:10 AM 6:20 AM 6:30 AM 6:40 AM 6:50 AM 7:00 AM 7:10 AM 7:20 AM 7:30 AM 7:40 AM

FWest

South

West

SCent

Coast

NCent

North

East

Dec. 22, 2007 Jun. 21, 2007

46

Appendix D – Sunset Times

Summer Solstice and Winter Solstice -- 2007

5:00 PM 5:30 PM 6:00 PM 6:30 PM 7:00 PM 7:30 PM 8:00 PM 8:30 PM 9:00 PM

FWest

South

West

SCent

Coast

NCent

North

East

Dec. 22, 2007 Jun. 21, 2007

Distributed Renewable Generation Profiling Methodology ERCOT Load Profiling March 4, 2008

Documents

Transcript of Distributed Renewable Generation Profiling Methodology ERCOT Load Profiling March 4, 2008