Once you have decided what size solar panel system you would like, the next stage is to judge what type of solar panels will meet your needs. This should not be decided based solely on price, as power efficiency, lifetime, warranty, and space needed are also important factors.
Too often people base their purchasing decisions on cost only, and then in two years wonder why no-one answers the phone from the “fly-by-night company” they purchased their solar panels from when the inverter dies or its output is cut in half. It’s also quite important to recognise that there are differing qualities of panels on the market and you should compare “apples with apples”.
There are 3 main types of panels: Monocrystalline, Polycrystalline, and thin-film or Amorphous, and you should recognize the advantages and disadvantages of each one. If your sole hurdle when buying panels is cost, then I suggest you compare “like with like”. It’s senseless to compare the price of Mono with the latest Amorphous panel and make your purchasing decision based on price alone.
One very important distinction to make with regards to solar panels is the range wattages on the market. Watts are related to the output of each panel, so a 200W panel would output 200 watts per hour. You can expect to pay double the cost of a 100W panel.
Solar PV (photo-voltaic) panels have a performance warranty that can last up to 25 years, and a guarantee of five to ten years. Also, your specialist can provide a warranty on workmanship, which will typically be five years. Ask your solar retailer who is providing the warranty, the name of the importer and/or manufacturer, and what you should do if something goes wrong.
If a cheap solar panel importer stops trading sometime in the future, their warranty obligation ceases. You are going to feel far more at ease with a well-known brand which has service agents for warranty work in Australia.
These are three main types of solar panel available, each with their own benefits:
Monocrystalline panels are a proven and reliable technology, used for the past 50 years and still popular today. They have the best conversion efficiency at 12-18% of all sunlight. Because these have the highest power to size ratio, they’re the best option if you’ve got limited roof space. They also degrade very slowly, generally losing 0.25 – 0.5% per year. Their lifespan can be 25 years, and even up to 50 years if looked after.
Monocrystalline cells don’t perform as well as other panels in shady conditions, and they are reasonably fragile. They are more expensive to manufacture due to their complexity.
Polycrystalline compares fairly well in performance and longevity to monocrystalline, and provides an efficiency of 12-13%. Well known brands include BP SX, Sharp and Kyocera.
Polycrystalline panels provide excellent longevity (around 25 years). They work best at 25 degrees C but will lose some efficiency at higher temperatures (over 50 degrees C), which is common in the Australian summer.
Amorphous Thin Film
Thin film panels typically have a lower efficiency at 6%, however, Cadmium Telluride Thin-Film panels (CdTe) have progressed to 11% efficiency. These are more suitable for inland Australian conditions where space is no problem and temperatures are hot. Amorphous panels do not lose energy in higher heats.
Disadvantages are: Lifespan is reduced; there is a 3-6 month breaking-in period; and they typically require 2-3 times the roof space for the same output of crystalline cells.
When choosing solar panels remember to focus on the goal of recouping your set-up costs through savings in electricity. The more efficient and higher watt panels will achieve this faster. However, if you are looking at solar farms in Outback Australia where temperatures regularly go above 40 degrees celcius and there is some cloud cover (these panels also work much better in the shade}, then these panels may be suitable.
The Requirements of Solar Panels
With all types of solar panels, the owner must ensure they are maintained and kept free from dirt and shade, because these factors affect solar power output.
Panels are installed facing north and at a roof angle of a minimum 10 degrees. Do the solar panels you’ve budgeted for actually fit in the space you want to install them? Each solar panel is about 1.6 m long by 0.8 m wide. A 1.5kW solar panel system requires around 12 m of north-facing roof space. As mentioned, this footprint varies depending on the type of panel. Don’t worry if you can’t work out the amount of unshaded space the roof has for your panels, because your specialist will calculate it precisely when quoting. You may want to be conservative with the space, though, in the event you wish to add more panels later to cover more of your energy needs.
My Solar Price specialise in solar power, solar hot water, and solar pool heating quotes. For three free quotes you can visit My Solar Price.