Many Australians believe cold weather negatively impacts the performance of solar panels.
It’s a common misunderstanding. Solar energy output is dependent on sunlight, not heat.
Solar panels and solar systems work in winter. While output may reduce in some areas during colder months, it never disappears. In some parts of Australia, solar works better in winter than summer.
While a typical solar system will perform better on some days than others, there are no days when zero solar energy is produced.
This includes the winter month of June, the worst month for solar output in most of Australia.
While July is the coldest month in most of Australia, June is the worst for solar energy output because of the winter solstice. This is the shortest day of the year with the shortest time available to generate solar energy.
Darwin has a higher solar energy output in winter than summer because of tropical weather patterns and less variance in day length.
In the tropics, summer brings the big wet with cloudy skies and endless rain. While winter brings the big dry, clear skies and abundant sunshine.
Average daily generation of a north-facing rooftop solar system in June varies greatly between Australian cities. The following figures show June solar generation as a percentage of the annual daily average city by city.
Darwin: 112 percent
Brisbane: 75 percent
Sydney: 71 percent
Perth: 66 percent
Canberra: 60 percent
Adelaide: 57 percent
Melbourne: 57 percent
Hobart: 49 percent
The percentage of annual daily solar generation falls the further south the city and the further away from the equator.
The easiest way to enhance solar generation during winter months is to install a larger solar system.
A 10-kilowatt solar system will provide 52 percent more energy than a 6.6-kilowatt system. Adding more solar panels, using energy-efficient reverse cycle air-conditioner for heating and improving a home’s gaps, glazing and insulation will improve performance and lower consumption.
The panels may be adjusted to increase the amount of energy they produce in the winter.
This is a great idea for off-grid systems installed on the ground. Rooftop solar panels, on the other hand, rarely make sense due to the high cost of tilt racks.
North-facing panels will produce the most winter production at the angles shown below.
Darwin: 46 degrees
Brisbane: 53 degrees
Perth: 58 degrees
Adelaide: 58 degrees
Canberra: 59 degrees
Sydney: 60 degrees
Melbourne: 62 degrees
Hobart: 67 degrees
Installing a battery allows the storage of excess solar energy for use at times when the sun isn’t shining.
Quality solar batteries are becoming increasingly affordable. Especially with government rebates and incentives. Investing in a solar system with battery capacity allows for the easy addition of future storage capacity.
Before long solar batteries will be common on most solar systems.
“Most homeowners worry about rising electricity bills so we create custom solar plans to ensure you never face outrageous bills ever again.”
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