Choosing solar panels in Brisbane can be a confusing exercise. Gio Tech have the experience and ‘know how’ when it comes to choosing the best solar panels for your property. We can advise and help you throughout this process to ensure you will get solar panels that best suit your needs.
When I was buying solar panels for my house in the early days, I was obsessed with trying to get a panel with the highest efficiency, thinking that surely the most efficient panels were the best. The problem is that what the manufacturers quote as their efficiency rating, is not particularly relevant in deciding the most cost effective option.
Solar Panel Efficiency
Solar panel efficiency is a measure of how much energy the panel produces per square metre. So, a more efficient 250 Watt panel will be smaller than a less efficient 250W panel and take up less space on your roof. However, in the end both will produce 250 watts of power.
Panel efficiency is only really an issue if you are trying to squeeze the maximum possible electrical energy out of a particular roof space. You would then choose the most efficient available panel to fill your roof and extract every possible Watt of power from the available sunlight. However, more efficient panels, particularly the Panasonic (ex-Sanyo) hybrids, are a lot more expensive so that you may be paying a large amount extra for just a few extra units of electricity.
I can never understand it when I drive past and see hybrid panels that only cover half the roof. The owners have been completely mis-sold a much more expensive system, in the belief that they will generate more because Sanyo/Panasoinc panels are “the best”. There would still have been space on the roof to fit standard mono or polycrystalline panels, which would generate the same amount of electricity, but for a much lower installation cost.
Most people are really trying to get the best possible value out of their roof space, in order to get the best return on their investment. Better, more useful measures of “efficiency” are:
- Cost per kW – the cost per kilowatt of installed power.
- kWh per kW – number of units of electricity (measured in kWh) generated per year per kilowatt of installed power
- Or even Cost per kWh – the overall price per unit of electricity generated over the lifetime of the system
If you compare one 4kW system, with another one, it is usually best to choose the one that costs you least, providing they are both going to be installed to the same standard. However, the cheapest panels do not always produce the most electricity so that sometimes it might be better to pay a little more for better quality panels that are proven to generate more electricity. That is why you need to speak with the Brisbane solar panel experts – Gio Tech.
One of the best reports to look at is produced by a German Test Laboratory called Photon. They have a field of panels from a range of different manufacturers and carefully measure their outputs to find which produce the highest outputs over a year, measured in kWh / kW. You can read the latest Photon Test report here. Their tests over the last couple of years have consistently put manufacturers such as REC at the top for giving the highest annual output.
The report shows that if you put a 250W REC panel next to a 250W panel from most other manufacturers, it will produce at least 2-3% more electricity over a year. So, providing the REC panel is not much more expensive, it would be worth paying a little more to get the extra electricity. This is why we have primarily fitted REC panels over the last year or so. However, we are also now quoting a number of different Chinese manufactured panels. Although they may not produce as much electricity, they are cheaper than REC, so that overall you get a better return on your money and get better value from your Brisbane solar panels.