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Energy from the sun can be used to generate electricity (solar-electric), or heat (solar-thermal). Victoria has excellent solar resources, for example, Mildura receives 90% of Brisbane 's solar radiation levels. Victoria's average yearly global solar exposure on a horizontal surface ranges between 12-20 Megajoules per square metre per day (MJ/m2/day).

View Victoria's solar resources on an interactive map.

The irradiation on a horizontal surface will vary from the average value throughout the year. Seasonally, the winter average will be lower and the summer average will be higher. The Bureau of meteorology has more detailed data from satellite measurements.

Key: Average Yearly Global Solar Exposure (MJ/sq. m)

Average Yearly Global Solar Exposure figures were sourced from the Bureau of Meteorology

Variations in Solar Radiation

Solar hot water systems and Photovoltaic systems are generally installed on an angle facing northward. When installed facing at appropriate direction and at the correct inclination the amount of solar irradiation (energy) falling on a surface can be considerably greater than that falling on a horizontal surface.

Examples from the Australian Solar Radiation Data Handbook illustrate that in summer the amount of solar irradiation is similar for a sloped surface and a horizontal surface. However, in winter a surface on a 30° slope will receive up to 60% more than a horizontal surface.

External related links

Bureau of Meteorology Solar Radiation Definitions

Bureau of Meteorology satellite measurements