Last week, one of our clients from Aruba asked an interesting question:
"Should our solar carport use Q275 steel and SUS316 stainless steel because Aruba is an island?"
It's a great question, and one that many project owners ask when designing solar carports in coastal environments.
Here is our recommendation.
1. Structural Steel: Why Q235B Is Still the Industry Standard
For most solar carport structures, the industry standard is to use Q235B carbon steel for columns and beams, protected by hot-dip galvanizing.
While many suppliers provide a zinc coating of around 65 μm, our standard specification is at least 80 μm, and for highly corrosive coastal or island environments such as Aruba, we generally recommend increasing the coating thickness to 100 μm or more whenever the project budget allows.
Many customers also ask whether Q275 steel is a better choice.
In practice, the answer is not necessarily.
Compared with Q235B, Q275 offers higher yield strength, but for most solar carport designs this additional strength provides very limited practical benefit. Structural performance is usually governed by the engineering design rather than simply selecting a higher-strength steel grade.
Of course, Q275 can be supplied when required, but it is typically a customized solution and usually requires larger production quantities.
2. Rails: Why We Prefer S350GD + ZAM275
For roll-formed components such as solar rails that do not require welding, we normally recommend S350GD steel with ZAM275 (Zinc-Aluminium-Magnesium) coating.
Compared with conventional galvanized steel, ZAM offers several advantages:
· Excellent corrosion resistance
·Outstanding cut-edge self-healing performance
· A smoother and more attractive surface finish
These characteristics make it an ideal choice for long-term outdoor solar applications.
3. Fasteners: SUS304 or SUS316?
Fasteners are often overlooked, but they play an important role in long-term reliability.
For island or coastal projects like Aruba, SUS316 stainless steel is generally recommended whenever the budget permits, as it provides better resistance to chloride corrosion than SUS304.
4. Should the Entire Carport Be Made of SUS316?
Another question we often receive is:
"Can the entire solar carport be manufactured from SUS316 stainless steel?"
Technically, yes.
However, from an engineering and commercial perspective, it is usually not the most cost-effective solution.
Using SUS316 for the entire structure significantly increases material costs, while the improvement in structural performance is relatively small. In most projects, the additional investment does not translate into proportional long-term value.
Our Recommended Material Combination
After evaluating structural performance, corrosion resistance, service life and project cost, we typically recommend the following combination:
• Columns & Beams: Q235B carbon steel with hot-dip galvanizing (≥80 μm, preferably ≥100 μm for coastal environments)
• Solar Rails: S350GD + ZAM275
• Fasteners: SUS316 stainless steel
This combination provides an excellent balance between structural strength, corrosion resistance, durability and overall project cost, which is why it has become the preferred solution for many commercial and industrial solar carport projects.
Every project is different. The optimal material selection should always consider the local climate, structural requirements, design life and budget—not simply choosing the highest-grade material available.
Good engineering is about selecting the right material for the right application, rather than the most expensive one.
If you have a special need for solar mounting structure, feel free to contact us for the solutions.
CORIGY SOLAR more professional and flexible solar mounting solutions waiting for you here! CONTACT US!
Above news from CORIGY SOLAR Sales & Marketing department
Phone: +0086-592-6883200
E-mail: sales@corigy.com
IPv6 network supported
English
español
한국의
