SLIDE 1

ROOFTOP PV FORECASTING

August 2012

PRESENTED BY ANDREW REDDAWAY

SLIDE 2

ROOFTOP PV AND AEMO

• Rooftop PV masks household and business demand.

• Impacts energy and Maximum Demand (MD) MD.

• Rooftop PV generation is now included in forecasts for electricity demand.o Separate rooftop PV from demand history.o Include as a separate item in forecasts.

SLIDE 3

ROOFTOP PV INFO PAPER 2012

• Published on AEMO’s website:http://www.aemo.com.au/en/Electricity/Forecasting/2012-Information-Papers

SLIDE 4

PROCESS OVERVIEW

ForecastHistorical capacity

Installed capacity

Future capacity

Historical solar intensity

Sunlight

Historical energy

Energy generation

Future energy

Historical generation

Maximum demand

Future generation

Samples of system output

Actual generation

SLIDE 5

HISTORICAL CAPACITY

There is no perfect data source for installed capacity.

Requested from all 13 DBs in the NEM.• Monthly from 2008.• Filled in data holes.

ORER • Higher than DB data in early period.• Time lags are inherent.

SLIDE 6

HISTORICAL CAPACITY - NEM

SLIDE 7

INTERESTING SOLAR INSTALL NO. 1

SLIDE 8

SUNLIGHT

• Actual monthly sunlight intensity data from BOM

SLIDE 9

HISTORICAL GENERATION - MODEL

• Initial model is simple.• Capital city proxy for region• Annual generation from CEC consumer guide

o kWh expected from a 1 kW system, daily avg. over a year

SLIDE 10

HISTORICAL GENERATION - MODEL

• Monthly % splits from “pvwatts” engineo Draws on its own climate datao Assume north orientation, tilt = latitude

SLIDE 11

HISTORICAL GENERATION – MODEL VALIDATION

• Sample rooftop system generation data from pvoutput.org

SLIDE 12

INTERESTING SOLAR INSTALL NO. 2

SLIDE 13

HISTORICAL GENERATION – MODEL VALIDATION, MELBOURNE

0.00

200.00

400.00

600.00

800.00

1,000.00

1,200.00

1,400.00

1,600.00

1,800.00

Mon

thly

ene

rgy

(kW

h)

Date

Sample Estimate

SLIDE 14

INSTALLED CAPACITY FORECASTS

• Forecasts of Rooftop PV growth consider the following drivers:o Electricity price increaseso Technology costs for solaro Government subsidies

• And barrierso Saturationo Network constraints

SLIDE 15

SATURATION

Assumptions for saturation level:• 75% of suitable dwellings have a rooftop PV system• Average system size: 3.5 kW• Allowance for commercial buildings

• Study by Entura: City of Port Phillip – 4 kW per dwelling.

SLIDE 16

ECONOMIC PAYBACK

Installation Year Slow Uptake scenario Moderate Uptake scenario Rapid Uptake scenario

2015 8 to 11 years 6 to 9 years 4 to 7 years

2020 7 to 9 years 5 to 6 years 3 to 4 years

2025 5 to 7 years 3 to 4 years 1.5 to 2 years

2032 5 to 6 years 3 years 1.5 to 2 years

For individual household installations:

SLIDE 17

NEM INSTALLED CAPACITY FORECAST

-

5,000

10,000

15,000

20,000

25,000

Inst

alle

d ca

paci

ty (M

W)

Year

NEM saturation Estimated Actuals Slow Uptake Moderate Uptake Rapid Uptake

SLIDE 18

NON-AEMO CAPACITY FORECASTS

-2,000

3,000

8,000

13,000

18,000

23,000

Inst

alle

d ca

paci

ty (M

W)

Year

NEMSat AEMO Slow Uptake AEMO Moderate Uptake AEMO Rapid Uptake ACIL Tasman

Estimated actuals Sunwiz Slow Uptake Sunwiz Moderate Uptake Sunwiz Fast Uptake SKM/MMA

GEM ROAM low ROAM medium ROAM high DRET

Suntech BREE AER BeyondZero

SLIDE 19

INTERESTING SOLAR INSTALLATION 3

SLIDE 20

NEM ENERGY – ROOFTOP PV

SLIDE 21

VIC ENERGY – ROOFTOP PV

SLIDE 22

VIC ENERGY – SCENARIO 3 PLANNING

Rooftop PV 2.58%

Rooftop PV 5.01%

SLIDE 23

VIC MD DAY GENERATION CURVE

0%

10%

20%

30%

40%

50%

60%

70%

80%

Perc

enta

ge o

f rat

ed c

apac

ity (%

)

Hour

SLIDE 24

VIC MD FORECAST – ROOFTOP PV

3.14% of total MD

6.79% of total MD

SLIDE 25

RECAP: KEY POINTS

• Rooftop PV offsets energy and MD.• Fast-changing area. Impacted by government policy.• Already significant uptake (1.5 GW in the NEM),

and growing (say 12 GW in 2031).• Lots of headroom before hitting saturation level.• Network constraints are an issue.• Potential to align PV generation better with system MD.• Room to improve our analysis and understanding,

especially for MD.

• PV now included as a component in AEMO forecasts.

SLIDE 26

DIVIDER SLIDE