Implications for Load Shapes and Forecasting

April 28, 2017

Battery Energy Storage

2

TOPICS

» What is Energy Storage

» Storage Market, Costs, Regulatory Background

» Behind the Meter (BTM) Battery Storage

• Where is it used?

• How is it used?

• Real world examples (California research)

» How to analyze storage?

• Simulations vs. Data

» Where is the market going?

3

WHAT IS ENERGY STORAGE?

» The capture of energy produced at one time for use at

a later time.

Pumped Hydro Compressed Air Batteries

4

BATTERY ENERGY STORAGEDominating technologies

» Dominated by Lithium Ion Batteries followed by flow

batteries

5

BATTERY ENERGY STORAGESize categories

» Transmission connected

» Distribution Connected

» Behind the Meter

Source: Rocky Mountain Institute

6

WHY STORAGE NOW?

Falling Costs

• Tesla Gigafactory

Rising Demand Charges

• Now make up 50% or more of commercial bills

More Intermittent Renewables

• Balance variability

• Offer the ability to line up peaks

Reliability

• Power Outages

• Hurricane Sandy

7

BATTERY ENERGY STORAGEGrid Scale

» Catastrophic leak Oct. 2015 at Aliso Canyon natural gas storage

facility threatened to cause power outages across Southern CA

» 70 MW of energy storage deployed in 6 months

Source: Greentech Media

8

BATTERY ENERGY STORAGEBehind the Meter – C&I

9

BATTERY ENERGY STORAGEBehind the Meter – Residential

10

U.S. ANNUAL DEPLOYMENT FORECASTAdvanced Energy Storage, 2012-2021 (MW)

Source: Greentech Media

11

CAPITAL COSTS

» Tesla data point remains unproven -claims to be ~½ price of prior

versions…

Lithium Ion BTM

Source: Itron DG Cost Effectiveness Model

12

BTM STORAGE REGULATORY DECISIONSRegulatory Background

» California Self-Generation Incentive Program modified to

included standalone storage in 2011

• Most recently program funding doubled to $166 million per

year (85% storage allocation)

» California Public Utilities Commission (CPUC) mandated 1,325

Megawatts of storage by 2024

» Hawaii and Australia reformed tariffs to encourage self-

consumption

» New York, Massachusetts, and New Jersey provide incentives for

energy storage

CALIFORNIA BTM RESEARCHSelf-Generation Incentive Program

14

HOW IS BTM STORAGE BEING USED IN CA?

» Backup Power

» PV Self-Consumption

» Demand Charge

Reduction

» TOU Bill Management

» Aggregated Demand

Response

What we know so far

15

WHERE IS BTM STORAGE BEING DEPLOYED?What we know so far

Note: SGIP is ~18% of estimated U.S. annual deployment at 2016

16

WHERE IS BTM STORAGE BEING DEPLOYED?What we know so far

Non-Res

SGIP DATA ANALYSIS

» Collected interval performance data from storage systems,

merged with AMI data

• Aggregated results: 2015

• Individual case studies: 2016

» Focused on customer energy and peak demand

• Coincident and non-coincident demand

» Residential and Non-Residential

• PBI = Large C&I

During 2015

17

NON-RESIDENTIAL (C&I) STORAGE

PROJECTS

19

ENERGY IMPACTDistribution of 15-Minute kWh Charge/Discharge

15-Min Charge / Discharge kWh

• Most (+80%) of the time systems are idle

• Charge/Discharge patterns are fairly “symmetrical”, so annual energy impact is

negligible

20

METRICS: ROUND-TRIP EFFICIENCY

RTE = total kWh of discharge from the storage project

total kWh of charge

Non-residential AES projects, 2014 - 2015

Program

Requirement:

63.5% annual RTE

21

CASE STUDY 1 – CITY GOV. BUILDING2016 Data, “Narrow” Peak

Calculated Load

AMI Load

Storage Discharge (+) /

Charge (-)

22

CASE STUDY 2 – CITY GOV. BUILDING2016 Data, “Wide” Peak

Calculated Load

AMI Load

Storage Discharge (+) /

Charge (-)

23

CASE STUDY 3 – CITY GOV. BUILDING2016 Data, DR Example

Calculated Load

AMI Load

Storage Discharge (+) /

Charge (-)

24

CASE STUDY 4 – CITY GOV. BUILDING2016 Data, Another DR Example

Calculated Load

AMI Load

Storage Discharge (+) /

Charge (-)

25

CASE STUDY 5 – GROCERY STORE / EV CHG.2016 Data, Idle

Calculated Load

AMI Load

Storage Discharge (+) /

Charge (-)

26

SMALL C&I PROJECTS (NON-PBI)

1 2 3 4 5 6 7 8 9 10 11 12

0 -0.12 -0.10 -0.11 -0.07 -0.12 -0.14 -0.12 -0.18 -0.10 -0.09 -0.08 -0.08

1 -0.18 -0.09 -0.14 -0.10 -0.08 -0.08 -0.06 -0.12 -0.07 -0.07 -0.12 -0.15

2 -0.06 -0.12 -0.10 -0.09 -0.11 -0.05 -0.04 -0.13 -0.06 -0.10 -0.13 -0.18

3 -0.13 -0.13 -0.10 -0.12 -0.16 -0.03 -0.06 -0.10 -0.05 -0.07 -0.09 -0.14

4 -0.19 -0.23 -0.05 -0.15 -0.16 0.00 -0.04 -0.05 -0.05 -0.06 -0.09 -0.13

5 -0.27 -0.15 -0.07 -0.13 -0.10 -0.13 -0.16 -0.20 -0.08 -0.09 -0.12 -0.16

6 -0.30 -0.04 -0.09 -0.05 -0.12 -0.08 -0.09 -0.14 -0.07 -0.04 -0.10 -0.09

7 -0.19 -0.06 -0.12 -0.13 -0.15 -0.11 -0.10 -0.15 -0.09 -0.05 -0.12 -0.13

8 -0.32 -0.18 -0.21 -0.23 -0.25 -0.28 -0.25 -0.23 -0.14 -0.11 -0.11 -0.17

9 -0.23 -0.28 -0.18 -0.22 -0.19 -0.31 -0.27 -0.24 -0.12 -0.11 -0.14 -0.12

10 -0.19 -0.23 -0.29 -0.32 -0.23 -0.31 -0.23 -0.31 -0.17 -0.15 -0.06 -0.04

11 -0.26 -0.17 -0.35 -0.32 -0.37 -0.32 -0.31 -0.36 -0.21 -0.22 -0.04 0.00

12 -0.21 -0.01 -0.14 -0.07 -0.12 -0.24 -0.20 -0.16 -0.07 -0.02 -0.03 -0.05

13 -0.33 -0.32 -0.29 -0.29 -0.21 -0.35 -0.26 -0.15 -0.11 -0.06 -0.15 -0.13

14 -0.20 -0.08 -0.15 -0.06 -0.11 -0.13 -0.12 -0.34 -0.29 -0.30 -0.13 -0.14

15 -0.22 -0.31 -0.29 -0.27 -0.25 -0.29 -0.28 -0.33 -0.25 -0.28 -0.25 -0.25

16 -0.16 -0.20 -0.22 -0.24 -0.25 -0.24 -0.19 -0.28 -0.23 -0.26 -0.22 -0.28

17 -0.10 -0.02 -0.11 -0.11 -0.16 -0.14 -0.11 -0.20 -0.14 -0.18 -0.17 -0.20

18 -0.17 -0.12 -0.16 -0.17 -0.18 -0.18 -0.19 -0.20 -0.15 -0.18 -0.16 -0.15

19 -0.18 -0.23 -0.19 -0.24 -0.18 -0.20 -0.17 -0.16 -0.13 -0.16 -0.15 -0.13

20 -0.15 -0.11 -0.12 -0.16 -0.14 -0.14 -0.15 -0.12 -0.12 -0.13 -0.11 -0.11

21 -0.15 -0.10 -0.12 -0.14 -0.14 -0.14 -0.12 -0.20 -0.12 -0.12 -0.11 -0.11

22 -0.15 -0.09 -0.12 -0.12 -0.12 -0.12 -0.12 -0.23 -0.11 -0.11 -0.10 -0.09

23 -0.15 -0.11 -0.10 -0.11 -0.14 -0.13 -0.13 -0.16 -0.10 -0.08 -0.05 -0.03

Month

H

o

u

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Total kWh of Discharge (Charge) per kW Rebated Capacity, Non-PBI Projects 2015

Charging not coordinated

27

LARGE C&I PROJECTS (PBI)

1 2 3 4 5 6 7 8 9 10 11 12

0 -0.05 -0.29 -0.39 -0.54 -0.94 -1.35 -1.43 -1.65 -1.63 -1.49 -1.18 -1.07

1 -0.04 -0.27 -0.31 -0.40 -0.56 -0.91 -0.73 -1.15 -1.14 -1.23 -1.55 -1.18

2 -0.04 -0.26 -0.28 -0.33 -0.19 -0.39 -0.18 -0.66 -0.56 -0.77 -1.27 -1.07

3 -0.04 -0.22 -0.22 -0.30 -0.07 -0.15 -0.11 -0.43 -0.31 -0.57 -0.79 -0.76

4 -0.04 -0.14 -0.19 -0.23 -0.05 -0.09 -0.06 -0.26 -0.16 -0.37 -0.59 -0.56

5 -0.03 -0.08 -0.18 -0.16 -0.03 -0.05 -0.04 -0.18 -0.11 -0.37 -0.45 -0.47

6 -0.02 -0.03 -0.13 -0.11 -0.02 -0.03 -0.02 -0.12 -0.07 -0.27 -0.39 -0.39

7 -0.01 0.00 -0.04 0.01 -0.02 0.00 -0.01 -0.01 -0.03 -0.17 -0.28 -0.31

8 -0.01 0.05 -0.01 0.12 -0.01 0.03 0.00 0.07 0.03 -0.02 -0.12 -0.16

9 0.01 0.07 -0.01 0.03 0.00 0.03 -0.05 -0.01 -0.02 0.08 0.02 -0.01

10 0.00 0.07 -0.01 0.03 0.02 0.06 -0.01 0.07 0.04 -0.02 0.06 0.00

11 -0.01 0.08 0.06 0.09 0.13 0.22 0.03 0.21 0.18 0.16 0.24 0.15

12 -0.01 0.07 0.11 0.09 0.12 0.37 0.08 0.29 0.20 0.23 0.28 0.27

13 0.02 0.07 0.10 0.09 0.14 0.44 0.11 0.26 0.24 0.20 0.28 0.16

14 -0.01 0.09 0.12 0.20 0.36 0.52 0.25 0.39 0.31 -0.17 -0.08 -0.22

15 -0.02 0.10 0.14 0.27 0.62 0.65 0.68 0.82 0.48 -0.17 -0.06 0.07

16 0.04 0.16 0.16 0.23 0.60 0.46 0.63 1.12 0.39 -0.10 0.01 -0.09

17 0.02 0.21 0.24 0.21 0.20 0.12 0.14 0.54 0.17 0.11 0.02 -0.03

18 0.00 0.18 0.24 0.21 0.18 0.17 0.26 0.53 0.88 1.23 0.44 0.28

19 0.01 0.14 0.17 0.12 0.19 0.26 0.48 0.68 1.06 1.51 1.58 1.34

20 -0.01 0.03 0.08 0.03 0.13 0.23 0.38 0.56 0.75 1.42 1.68 1.50

21 -0.01 -0.12 -0.11 -0.16 -0.57 -0.65 -0.72 -1.13 -0.97 -0.64 0.99 1.26

22 -0.05 -0.31 -0.20 -0.17 -0.45 -0.31 -0.08 -0.40 -0.49 -0.10 -0.71 -0.59

23 -0.05 -0.29 -0.30 -0.38 -0.94 -1.01 -0.98 -1.62 -1.31 -1.06 -0.11 -0.20

H

o

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Total kWh of Discharge (Charge) per kW Rebated Capacity, PBI Projects 2015

• Charging overnight, when energy is cheap, discharging in evening, when demand

is highest and energy most expensive

Large C&I (PBI) Projects Charge Overnight, Discharge in Evening

28

LARGE C&I (PBI) PEAK DEMAND REDUCTION

• Significant increase in non-coincident peak load reduction during summer

months, compared to the rest of the year

• PBI projects saved an average of ~$0.8 per kW rebated storage capacity in

demand charges

Average Non-Coincident Peak Load Reduction by Month, per Customer (PG&E)

29

2015 COINCIDENT PEAK IMPACTSOnly Large C&I (PBI) Project Contributed to Coincident Peak Demand Reduction

30

NON-RESIDENTIAL AES CO2 IMPACTS

» Generally

discharging during

higher marginal

emission hours

Alignment of grid emissions with charge/discharge

Large

C&I

Small

C&I

» With low efficiency,

net charging in all

hours

Marginal Emissions Compared to Aggregate Discharge (Charge), PBI Projects, 2015

0

0.2

0.4

0.6

0.8

-60-40-20

0204060

1 3 5 7 9 11 13 15 17 19 21 23Net

Dis

char

ge (

MW

h)

Hour of Day

Summer

Net Discharge Marginal Emissions

0

0.2

0.4

0.6

0.8

-60-40-20

0204060

1 3 5 7 9 11 13 15 17 19 21 23 Ton

s C

O2

per

MW

h

Hour of Day

Winter

Net Discharge Marginal Emissions

-0.1

0.1

0.3

0.5

0.7

-2

-1.5

-1

-0.5

0

1 3 5 7 9 11 13 15 17 19 21 23

Net

Dis

char

ge (

MW

h)

Hour of Day

Summer

Net Discharge Marginal Emissions

-0.1

0.1

0.3

0.5

0.7

-2

-1.5

-1

-0.5

0

1 3 5 7 9 11 13 15 17 19 21 23

Ton

s C

O2

per

MW

h

Hour of Day

Winter

Net Discharge Marginal Emissions

Marginal Emissions Compared to Aggregate Discharge (Charge), No-residential, Non-PBI Projects, 2015

31

NON-RESIDENTIAL CO2 IMPACTS

» Net increase in GHG

emissions for both large

and small C&I systems

» Round trip efficiency losses

outweigh GHG savings for

large C&I systems despite

on-peak discharge

» More variable discharge for

small C&I larger

increase in GHG emissions

» Note: these impacts do not

include the contribution of

storage to integrating

renewables

Population of estimates

Large

C&I

Small

C&I

RESIDENTIAL STORAGE PROJECTS

33

RESIDENTIAL PROJECTS

1 2 3 4 5 6 7 8 9 10 11 12

0 -0.28 -0.25 -0.28 -0.25 -0.26 -0.26 -0.28 -0.29 -0.29 -0.29 -0.24 -0.26

1 -0.28 -0.25 -0.28 -0.25 -0.26 -0.26 -0.29 -0.29 -0.29 -0.29 -0.24 -0.26

2 -0.28 -0.27 -0.28 -0.25 -0.26 -0.26 -0.29 -0.29 -0.29 -0.29 -0.25 -0.26

3 -0.28 -0.25 -0.28 -0.25 -0.26 -0.26 -0.29 -0.30 -0.29 -0.29 -0.25 -0.27

4 -0.29 -0.25 -0.28 -0.25 -0.26 -0.26 -0.29 -0.30 -0.29 -0.29 -0.26 -0.27

5 -0.28 -0.25 -0.28 -0.25 -0.27 -0.27 -0.29 -0.30 -0.29 -0.29 -0.26 -0.27

6 -0.28 -0.25 -0.28 -0.32 -0.50 -0.54 -0.48 -0.37 -0.30 -0.29 -0.26 -0.28

7 -0.28 -0.26 -0.44 -0.78 -1.10 -0.94 -0.97 -0.79 -0.61 -0.44 -0.30 -0.28

8 -0.31 -0.62 -1.47 -2.25 -2.59 -2.20 -2.19 -2.05 -2.00 -1.84 -1.12 -0.50

9 -1.50 -2.17 -3.65 -3.30 -2.73 -3.06 -3.77 -3.91 -3.87 -4.08 -3.42 -1.89

10 -2.90 -2.85 -1.71 -0.64 -0.47 -2.05 -2.95 -2.88 -3.16 -3.47 -5.18 -3.07

11 -1.60 -0.46 -0.31 -0.45 -0.31 -2.14 -3.58 -3.29 -3.42 -2.92 -6.04 -2.36

12 -1.05 -0.33 -0.29 -0.44 -0.35 -2.05 -4.01 -3.53 -3.76 -2.30 -5.95 -2.04

13 -0.72 -0.67 -0.36 -0.24 -0.37 -1.65 -3.81 -3.32 -3.24 -1.10 -3.23 -1.31

14 -0.82 -0.45 -0.56 -0.74 -0.83 -0.88 -1.63 -1.12 -1.22 -0.17 -0.56 -0.89

15 -0.42 -0.44 -0.72 -0.50 -0.40 -0.61 -1.18 -0.56 -0.68 0.17 1.08 -0.55

16 -0.63 -0.55 -0.33 -0.36 -0.50 1.39 4.19 3.46 4.28 1.41 1.80 -0.07

17 -0.47 -0.52 -0.56 -0.55 -0.62 2.01 4.44 3.81 3.78 1.53 2.93 0.25

18 -0.22 -0.30 -0.48 -0.43 -0.50 2.79 4.54 3.56 3.25 1.62 3.30 0.26

19 -0.22 -0.21 -0.27 -0.31 -0.39 -0.47 -0.53 -0.42 -0.19 0.55 2.89 0.24

20 -0.24 -0.23 -0.27 -0.25 -0.26 -0.23 -0.25 -0.25 -0.24 -0.29 2.27 0.24

21 -0.27 -0.25 -0.27 -0.25 -0.26 -0.23 -0.25 -0.27 -0.27 -0.29 -0.23 -0.23

22 -0.28 -0.25 -0.27 -0.25 -0.26 -0.24 -0.27 -0.28 -0.27 -0.29 -0.24 -0.24

23 -0.28 -0.25 -0.27 -0.25 -0.26 -0.25 -0.28 -0.29 -0.28 -0.29 -0.24 -0.25

Month

H

o

u

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Total kWh of Discharge (Charge) per kW

Rebated Capacity, Residential Projects, 2015

• All residential projects in our sample are paired with solar

1 2 3 4 5 6 7 8 9 10 11 12

0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

4 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

5 0.00 0.00 0.00 0.04 1.37 5.22 1.24 0.04 0.00 0.00 0.00 0.00

6 0.00 0.00 0.72 33.84 132.22 160.17 117.25 45.73 6.02 0.56 0.01 0.00

7 0.43 3.61 89.60 302.35 492.07 402.76 412.66 305.38 198.64 89.79 13.29 1.20

8 70.69 240.20 738.17 1209.20 1426.98 1221.52 1205.92 1113.81 1065.01 960.35 516.22 120.95

9 751.56 1175.95 2077.80 1920.67 1643.83 1847.94 2238.92 2284.08 2249.48 2366.15 1940.27 1003.33

10 1681.15 1725.66 1089.06 502.17 435.73 1317.05 1854.55 1778.56 1934.10 2156.00 3044.13 1750.61

11 1211.06 585.37 431.15 494.85 436.46 1423.47 2274.63 2061.77 2124.16 1936.95 3624.31 1389.51

12 1054.19 545.29 499.39 554.83 508.31 1406.07 2567.07 2226.06 2360.23 1648.94 3687.04 1304.05

13 977.38 704.08 544.40 563.56 604.52 1257.41 2527.71 2148.21 2112.89 1082.45 2411.80 976.69

14 1031.63 629.47 716.49 832.44 918.46 895.37 1362.99 981.09 1061.76 774.02 1316.87 789.36

15 664.60 582.05 780.99 706.62 680.45 740.71 1084.70 643.98 748.22 786.27 736.53 613.50

16 526.38 519.67 478.07 511.51 633.21 795.12 448.78 433.37 374.86 594.82 412.73 351.38

17 247.94 341.06 416.54 451.67 548.50 458.04 405.89 341.22 354.30 356.38 150.26 97.80

18 13.75 111.18 238.62 266.92 336.40 310.78 331.93 285.48 217.36 60.59 0.91 0.25

19 0.00 0.19 18.75 98.44 180.85 246.09 279.27 177.88 23.03 0.02 0.00 0.00

20 0.00 0.00 0.00 0.11 7.08 35.61 30.37 2.88 0.00 0.00 0.00 0.00

21 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

22 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

23 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Month

H

o

u

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Total kWh of Solar Output,

Residential Projects, 2015

Box shows hours that correspond

with utility’s higher TOU rate

Appear to be charging from solar and responding to rates

WHAT’S NEXT?

» Storage prices will continue to drop, seeing a shift towards longer

duration storage (4hr vs 2hr)

» If utilities continue phasing out NEM tariffs, solar + storage value

proposition will increase

• Hawaii, Australia, Arizona, Nevada, California…

• In CA, SGIP will now prioritize projects paired with PV

» Increased demand charges -> increased storage

» Increased ability for utilities to control load

Rates, etc.

34

HOW TO THINK ABOUT STORAGE?

» Annual, monthly, and daily energy impacts are negligible (small

net increase)

» Impacts on the customer load shape are somewhat unpredictable

in both magnitude and timing

• Not all peaks are “shaved”

» We don’t expect to see any mitigation of the “duck curve” until

NEM or feed in tariffs are phased out

• Will lead to solar self consumption

35

HOW TO MODEL STORAGE?

» Dispatch models (AMI data + PV data + tariff + storage info)

• Typically assume perfect optimization based on load,

customer generation, and rates

• Not representative of current storage technologies

• Not representative of current

» Sub-metering

• Can be costly, not always actionable

36

KEY TAKEAWAYS FOR LOAD FORECASTING

» Energy impacts at all levels (customer/feeder/system) are

negligible

» Storage behavior can largely (albeit imperfectly) be predicted

based on tariffs

• Commercial customers with high demand charges will

primarily act to mitigate peak demand

• Residential customers on TOU rates will primarily act to shift

load across periods

• Customers on “NEM 3.0” tariffs will primarily act to maximize

PV self consumption

37

THANK YOU

www.itron.com

BACKUP

METRICS: STORAGE UTILIZATION

Storage discharge “capacity factor” defined as:

𝒌𝑾𝒉 𝑫𝒊𝒔𝒄𝒉𝒂𝒓𝒈𝒆

𝑯𝒐𝒖𝒓𝒔 𝒐𝒇 𝑫𝒂𝒕𝒂 ×𝑫𝒊𝒔𝒄𝒉𝒂𝒓𝒈𝒆 𝑪𝒂𝒑𝒂𝒄𝒊𝒕𝒚×𝟔𝟎%∗

Non-Residential 2014 and 2015

*60% represents the

SGIP Handbook

assumption of 5,200

discharge hours per yr

(5,200 / 8,760 = 60%)

40

0%

10%

20%

30%

40%

50%

60%

70%

1 3 5 7 9 11 13 15 17 19 21 23

Dis

char

ge C

apac

ity

Fact

or

Months of Data Available

PBI Non-PBI

• 18 of 21 (86%) PBI projects had capacity factors of at least 10% (required to

receive full PBI payment)