With the abundant sunlight in Australia, solar energy has become a perfect alternative to traditional energy sources in household and business properties. However, after installing solar panels, it often produces less output than rated on the system. Well, that’s because solar modules’ efficiency gets affected by many external factors.
Therefore, many brands focus on oversizing the PV array to ensure you get the maximum output without spending too much on other components. But what is oversizing, and how does it help in increasing the energy output? Find out more below.
What is Oversizing a PV array?
Oversizing refers to designing a solar PV array so that the solar panels can produce more power (DC) than the solar inverter can convert into AC power. It means you install more solar modules than the inverter can handle.
Generally, we install solar panels in an array delivering power equal to the inverter capacity. So no energy gets clipped or lost due to excess production. Right? While this looks like the perfect combination, it’s not always practical. A solar system may deliver 20% less energy than the promised amount because of solar module losses. Therefore, many companies have started offering mismatched solar power packages, like a 6.6 kW solar array with a 5kW inverter that can deliver maximum output.
Reasons Why You Should Oversize Your PV Array
1. Maximize Solar Energy During Peak Time
Most Australian states receive 6-8 hours of sunlight, making it suitable for harnessing maximum solar power to reduce electricity dependence. But because of changes in sun angle, panels may not receive proper sunlight throughout such a time window.
Therefore, oversizing your PV Array can work as an effective way to maximize solar energy during peak hours. Since PV prices have declined in the last few years, you don’t need to invest a lot to generate more power.
2. Effectively use Solar Inverter’s Capacity
PV modules have specific ratings based on their performance during Standard Test Conditions (STC). But in reality, these conditions change, causing the solar module to deliver less energy than the stated amount.
For instance, solar panels are tested at 25°C, while PV arrays operate at a higher temperature than 25° C during solar noon (when the earth receives maximum sunlight). It reduces the solar panel’s output by 20-25%. So by overpowering the PV array, you can increase the solar power and match it with the Inverters AC capacity.
3. Increase System’s Efficiency
The solar inverter works more efficiently when operating at maximum capacity. But unfortunately, solar panels don’t work at their full potential. It means they will deliver less DC to the inverter, impacting the efficiency of the inverter. So by oversizing the PV array, you will effectively increase systems efficiency.
4. Lower the Overall Cost of Solar Energy
When oversizing the PV array, you may find it costly due to the additional cost of racking the array and installing more panels. However, oversizing doesn’t require spending on the extra balance of systems.
So with the affordable prices of solar panels in Gold Coast, you can generate desired power without spending too much. It will eventually lower the overall cost of energy produced by the system.
5. Reduces the Cost of the Inverter
When you oversize a PV array, it will generate more DC power, helping you to match the inverter’s AC capacity. It means you don’t need to spend on the inverter with a higher AC capacity.
Hence, it will reduce the cost incurred on the inverter and make it relatively cheaper than the expenditure on total solar systems.
6. Minimal Replacement Costs
When you install solar panels, you may face situations where your solar inverter stops functioning after its warranty period. In such cases, it’s not always possible to replace it with the same type of inverter. So you can opt for a solar inverter with a lower capacity rating that will work perfectly with the solar array, minimizing the replacement costs.
How much can you oversize?
When oversizing the PV array, you can add as many panels as possible, considering it won’t exceed the inverter’s capacity and input voltage. However, CEC has restricted oversizing the solar array to 133% of inverter capacity. It means to benefit from subsidies (Small Technology Certificates) on your solar system’s upfront cost in Australia, solar PV array capacity shouldn’t exceed 133% of inverters rated output.
Moreover, this 133% applies when you don’t have DC-coupled batteries. But with batteries, you can extend the limits as your ability to offset carbon emissions increases. So you can take advantage of STCs on the additional solar modules.
Solar panels can get impacted by external factors that result in lower DC power and less AC output by the inverter. In such cases, oversizing your PV array is a cost-effective solution to maximize your system’s performance.
We hope all the reasons we have discussed above will help you to understand how oversizing a PV System benefit in increasing solar energy output.