Why Quality Counts ?

It’s very important when selecting the best solar panels to use for your solar power system installation to bear in mind a few crucial factors aside from the price tag. After all, your purchase decision is one you’ll be living with for a very long time and it should provide you with a good return on your investment.

Don’t base a buying decision on solar panel cost alone – the following are a few tips for choosing the quality solar panels.

Panel cost vs. value – other factors

As not all module manufacturers are equal and there are a variety of other factors that should influence your purchase decision rather than focusing solely on cost. Tolerance

This is the range a panel will either exceed or not meet its rated power. For example, a solar module you purchase may have a ‘nameplate’ wattage of 200 watts; but due to quality control issues, the output in ideal conditions may in reality only be 195 watts. A positive tolerance rating means the module will not only generate 200 watts, but perhaps more under standard testing conditions.

Temperature co-efficient

The temperature co-efficient rating is important to determine what the impact heat has on a solar panel’s operation after installation. The lower the percentage per degree Celsius, the better. The price of a module with low temperature co-efficiency can be a little more; but in Australia’s often hot conditions, a little extra cost can be worth it.

Conversion efficiency

The efficiency of how a solar panel converts light into electrical energy will determine how much power your system generates. If two solar panels cost the same, but one has a higher conversion efficiency; then that module provides the better value for money – assuming the claimed efficiencies are correct.

PID resistance

PID stands for potential-induced degradation. Caused by stray currents triggered by certain climate conditions; the phenomenon can cause substantial power loss. Good solar panels will display little or no PID.

LID resistance

LID stands for Light induced degradation; a process that occurs in the first few months after solar panels are installed. While this stabilises after a period, it can reduce the amount of power the module produces. A good solar panel will have little or no LID.

Embodied energy

Another important aspect to look at is the embodied energy of the solar panel – that is how energy intensive the production of the panel was and how quickly it will have paid itself back by producing more energy. Consider this aspect an environmental cost.

Durability / Longevity / Warranty

The durability or longevity of a solar panel warranty is important for a number of reasons – it can be an indicator of the manufacturer’s confidence in its products. Reputable solar panels will have a performance warranty a period of 25 years. All of our key modules; including REC Solar, feature this 25 year warranty period.

However, an important point to remember about warranty is that it will only be honoured for as long as the company operates. It’s another reason to select a well known brand of module rather than purchase an obscure low-cost brand that may disappear overnight.

As you most likely won’t be able to buy solar panels directly from the manufacturer, your selection of installer and retailer is also important. It’s best to choose an installation company that is a service agent for solar panel warranty work for the particular manufacturer you select. This is because if you do strike a problem, the turnaround time to a resolution will be far faster.

Size And Watts Capacity

The capacity of the solar panel in Watts will directly affect the cost, as solar panels are usually priced (and compared) in dollars per Watt. Watts are related to the output of each module; meaning a 100 Watt panel installed and operating under ideal conditions will generate 100 watt-hours of electricity each hour and a 200 Watt panel will generate 200 watt-hours each hour. Therefore, expect to pay up to double the price for the 200 Watt panel, compared to the purchase cost of a 100 Watt module.

The output of a panel also affects the physical size of the panel, meaning the 200 watt panel will be larger in size to the 100 Watt module. The type of solar cells used in its production also determines the size of the solar panel. They key issue to consider is that your system sizing is enough to power your appliances, and that the solar panels will physically fit in the area you wish to install them.

Your northerly facing roof space (and increasingly, west) is very valuable solar power real estate, so you’ll need to consider carefully your future plans. If you believe at some stage you will wish to install more solar panels, you need to ensure you’ll have the space to do so, otherwise you may find you’ll need to replace existing modules well before the end of their serviceable life.

Types of solar cells used

There are 3 main types of solar cells used in modules and the best type for you will vary depending on the installation application.

Monocrystalline silicon offers high efficiency and good heat tolerance characteristics in a small footprint.

Polycrystalline (or multi-crystalline) silicon cell based solar panels are now the most popular choice in residential installs. Recent improvements in polycrystalline panel technology have resulted in the development of modules equal to or better than many monocrystalline brands in terms of size, efficiency and heat tolerance. Two examples of leading polycrystalline modules are REC and JA Solar panels.

Amorphous (or thin-film) silicon uses the least amount of silicon. Thin film panels are generally less efficient than other solar cell types.

Questions? Contact our team of friendly experts for free, no-obligation advice on the best solar panels and full systems for your circumstances.