Installing solar panels is a great first step toward energy independence. But how do you make sure your system performs at peak efficiency all year round ΓÇö especially during winter when days are shorter and the sun sits lower in the sky? Here are our master engineers' top 7 tips to keep your solar system generating maximum power every single month of the year.
1. Optimise Your Panel Angle for Winter
In Australia, solar panels are typically installed at a fixed angle optimised for the annual average ΓÇö usually between 20ΓÇô35 degrees depending on your latitude. However, during winter the sun tracks lower across the sky, meaning panels benefit from a steeper tilt. If your installer used adjustable mounting brackets, we strongly recommend tilting your panels an additional 10ΓÇô15 degrees from June through August. The difference in output can be 12ΓÇô18% over the winter quarter.
2. Keep Panels Clean (Seriously)
A thin film of dust, pollen, bird droppings, or autumn leaf residue can reduce solar output by 15ΓÇô25%. This is particularly significant in winter when generation is already lower. Aim to clean your panels at least once before winter begins and once mid-season. Use a soft brush or squeegee with clean water. Never use abrasive cleaners or high-pressure water directly on panel surfaces.
"A dirty panel doesn't just look bad ΓÇö it's silently costing you money every single day." ΓÇö SunStack Chief Engineer
3. Monitor Your System Daily With Your App
Every SunStack installation includes access to a real-time monitoring portal. We strongly encourage homeowners to check their daily generation figures ΓÇö particularly in winter. If you see a sudden unexplained drop of more than 20% compared to the same day last week under similar conditions, this is a red flag that something needs attention. Early detection saves significant repair costs down the line.
4. Shift Your Loads to the Solar Window
In winter, the peak solar generation window typically narrows to approximately 9amΓÇô3pm compared to 7amΓÇô5pm in summer. Program your dishwasher, washing machine, pool pump, and EV charger to run during this midday window. If you have a battery, ensure your charge schedule is set to prioritise solar charging before any grid top-up. These simple behavioural adjustments can add 8ΓÇô12% to your effective self-consumption ratio.
5. Check for Shading Changes
Deciduous trees that were bare in summer and autumn may now be growing leaves, or new construction nearby may have changed your shading profile. Even partial shading on a single panel in a string system can reduce the output of the entire string. Our technicians can perform a shading analysis and, where needed, retrofit optimisers or microinverters to address this without replacing your system.
6. Inspect Your Inverter
Your inverter is the brain of your solar system. In winter, make sure the inverter display shows no error codes and that the output is consistent with weather conditions. Inverters installed in poorly ventilated roof spaces sometimes throttle output in extreme temperature ranges ΓÇö both hot and cold. Ensure vents are clear and unobstructed.
7. Consider Adding a Battery for Night-Time Use
In winter, the gap between your solar generation window and your evening energy consumption peak is at its widest. Without a battery, virtually all of your dinner-time, heating, and entertainment energy comes from the grid at retail rates. A battery bridges this gap completely. Most SunStack customers with a 10kWh+ battery cover 90%+ of their winter evening usage from stored solar, even on shorter days.
Book Your Winter Performance Check
SunStack offers complimentary system performance reviews for all customers. Our technicians will assess your angle, shading, inverter health, and battery state of health, then provide a written report with any recommended actions. Book yours online or call us on 1300 786 782.
