What Exactly is Daylight Savings?

Daylight Savings started as a way to get more daylight hours in the evenings during spring and summer. The Australian states that participate in daylight savings are NSW, Victoria, South Australia, Tasmania, and ACT.

Daylight Savings takes effect on the first Sunday of October setting the clock forward one hour and ends on the first Sunday in April at 3am setting the clock back to standard time.

Setting clocks forward allows for increased daylight times throughout the evenings and less in the morning, but does this affect energy consumption? How does it affect solar?

Instead, the only difference to your production is when the days get shorter, usually occurring around June during the Winter Solstice, which decreases the overall amount of solar production per day compared to summer.

The main difference of solar generation through daylight savings is the time periods that we consume energy. Because the daylight times are shifted further into the evening, solar can offset a large portion of energy consumption activities during the evenings like cooking dinner, which would usually be reliant on grid energy during standard time.

By using solar energy whilst the sun is out instead of peak grid electricity during evenings, it allows homes to cook dinner with renewable energy. Unlike daylight savings, the sun goes down relatively quickly in the evenings, forcing properties without battery storage to use grid electricity at night which drives energy costs up. We’ll touch more on battery storage later.

How Longer vs. Shorter Days Affect Solar Generation

Did you know that sunlight hours aren’t all the same?
During the year, Australia’s daytime duration varies depending on the occurring season, and this is what mostly affects overall solar production more than daylight savings times. Obviously, the panel conditions are another contributing factor to efficiency and production, but we’re mainly focused on seasonal changes and daylight savings.

Solar generation around summer vs. winter is much different, not just due to the difference in sun angles, but also the duration of daylight hours. Here is a chart that shows the amount of daylight hours during the year with times for sunrise and sunsets throughout Australia.

What are the Best Seasons for Solar Production? Winter or Summer?

From the time of writing this article, New South Wales is heading into the optimal months for peak solar production going from Spring into Summer. Over the course of November to February, solar production times peak with the days being longer and the sun more intense.

As the year passes, there are other seasonal factors that affect solar production throughout Newcastle and the Hunter, NSW.

The Sun’s Angle & Orientation

During spring and summer, daylight hours are generally longer, and the sun shines higher in the sky (around 78°) with increased intensity. Comparatively, Autumn and Winter typically get a lower angle of around 31° which results in less sunlight exposure and generation.

This page can give you a better understanding of the sun’s path during the year. (Latitude: 32.9283° S, Longitude: 151.7817° E, and you can use the month slider to see the differences). Note that this data is from 2014, but it should give you an idea.

In NSW, north-facing solar arrays are typically the best direction for maximum solar production. You’ll see some roofs across Newcastle with solar strings on different faces on the roof where they may point east for example. Due to the angle of the sun, summer is much more optimal for reaching all faces efficiently.

Does changes in UV levels affect Solar Generation?

Yes, ultraviolet (UV) levels can affect solar generation, but not in the way you’d expect.

Generally, solar panels aren’t directly affected by changes in UV light as it is different to visible and infrared light. Panels like monocrystalline panels are designed to harness that visible and infrared light and is less sensitive to UV light.