How To Choose The Best Solar Panels in NZ

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How To Choose The Best Solar Panels in NZ

My Solar Quotes lists only premium solar power installation companies, and the companies must be SEANZ members. These companies have done their research to find the best solar panels available, not only in terms of quality, but also price and efficiency.

Should you want to conduct your own research, please see the information below about the types of solar panels available, tier rated solar panels and understanding solar panel specifications.

Types of Solar Panels

The 3 main types of solar panels are; monocrystalline, polycrystalline and thin film. Monocrystalline is the most sought after panel, and polycrystalline is following closely behind. With around 1% difference, monocrystalline is fractionally more efficient, and expected to last a year or two longer. Thin film panels are the least efficient and generally the cheapest, with polycrystalline and monocrystalline having a higher price point.

Because monocrystalline panels are more efficient, they generate more solar power within a smaller roof area. If you have limited space for solar panels you might want to consider monocrystalline solar panels.

solar panel types - monocrystalline, polycrystalline, thin film

BIPV ( Building Integrated Photovoltaics)

BIPV solar replaces conventional building materials such as roof tiles, skylights and glass windows.

Only a limited number of BIPV panels have been installed in New Zealand (this is due to the substantial cost).

Examples of BIPV panels include: Tesla’s solar roof tiles, glass on glass solar panels and transparent solar glass.

Zero Energy Home Auckland

The Zero Energy home in Auckland (pictured above) used solar tiles.  Read more information here.

Solar Power Skylights

Above is an example of solar power skylights.

Selecting Solar Panels By Tiers

The tier system is how the solar power industry grades solar panels.   

Tier 1 – Considered to be the best solar panels. Manufacturers are vertically integrated; they have control over the entire manufacturing process. They use the highest-grade silicon solar cells and are the highest performing solar panels.

Tier 2 – These panels do not necessarily have substandard quality compared to Tier 1, they just don’t have control over the whole process. They spend less on R&D, but they still keep up with the latest developments on design and construction.

Tier 3 – These manufacturers are the largest percentage in the market. Often tier three businesses only assemble the parts and source their products on the open market.  These panels aren’t recommended by My Solar Quotes.

Solar panel tier rating system pyramid diagram

Find out how the perform in real world conditions:

Below are just a few of the specifications to look for on solar panel data sheets.  Data sheets will normally be provided if you request quotes. For more in-depth details on solar panels, specifications click here.

Performance Data to look out for:

Power Tolerance

Each solar panel manufacturer claims a specific power output for their solar panels e.g. 250W.  However, manufacturers also indicate the range a solar panel is expected to exceed. Most companies indicate both a negative and positive tolerance. The range can vary as much as +10% to -10%. If this is the case, then a 250W panel could produce as much as 275W or as little as 227W in ideal conditions. To ensure expected power output, look for solar panels with a small power tolerance range or a positive only tolerance.

Temperature co-efficient rating

This rating describes the decreasing power output as the outside temperature increases.  Temperature coefficient Pmax for Trina Honey Solar Panels is -0.41%, therefore each degree over 25˚C the maximum power output of the panel is reduced by 0.41%.

Efficiency

The efficiency percentage specified for a solar panel shows how much of the sun’s energy that hits the solar panel transforms into electricity.  For example, the Yingli’s Panda Series 290W panels have an efficiency of 17.9%. Efficiency ratings average range is between 15% to 21%.  

Generally, the more efficient a solar panel is, the higher the cost.

Warranties on Solar Panels

Most solar panel manufacturers have a performance warranty of 25 years, which indicates the manufacturer is confident that their solar panels will last 25 years, if not longer.

It is important to know that a warranty will only be honoured if the company is still in operation. If they are not in operation, the performance warranty could still be covered, so long as the company was insured when you purchased the panels.

Therefore, selecting a solar manufacturer that has a good history is worthwhile.