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:

SLIDE 4 PROCESS OVERVIEW

SLIDE 5 HISTORICAL CAPACITY There is no perfect data source for installed capacity. Requested from all 13 DBs in the NEM. Monthly from 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” engine o Draws on its own climate data o 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

SLIDE 14 INSTALLED CAPACITY FORECASTS Forecasts of Rooftop PV growth consider the following drivers: o Electricity price increases o Technology costs for solar o Government subsidies And barriers o Saturation o 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 For individual household installations:

SLIDE 17 NEM INSTALLED CAPACITY FORECAST

SLIDE 18 NON-AEMO CAPACITY FORECASTS

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

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