8 types of Solar PV mounting structures for your rooftop solar system

Solar PV mounting structures are an essential component of any solar rooftop system. They provide a stable and secure platform for solar panels, ensuring they are optimally positioned to receive sunlight and generate electricity. With a variety of mounting structures available, it can be challenging to choose the right one for your solar rooftop system. In this blog, we will explore the different types of solar PV mounting structures.

1. Fixed-Tilt Mounting Structures

2. Adjustable Tilt Mounting Structures

3. Tracking Mounting Structures

4. Ballasted Mounting Structures

5. Integrated Mounting Structures

6. Flush Mounted Structures

7. East-west mounting structures

8. High-rise or elevated structures

Fixed-Tilt Mounting Structures

Fixed-tilt mounting structures are the simplest and most common type of solar PV mounting structures used in solar installations. These structures are designed to keep the solar panels at a fixed angle, usually between 15 and 45 degrees, depending on the latitude and orientation of the rooftop. The optimal angle for fixed-tilt structures is typically determined by the location of the installation, with steeper angles used in locations with lower levels of sunlight and shallower angles used in locations with higher levels of sunlight.

Pros

1. Cost-effective

2. Easy to install

3. Low maintenance

Cons

1. Lower energy output as they are at a single angle

2. Limited flexibility

Adjustable Tilt Mounting Structures

Adjustable tilt mounting structures, also known as tilt-angle flexible structures, is a type of solar PV mounting structure that allows the angle of the solar panels to be adjusted manually according to the changing seasons and solar angles. The optimal tilt angles are periodically adjusted (monthly, seasonal, and semi-annual) depending on the sun’s position throughout the year.

Pros

1. Increased energy output

2. Better performance in shading conditions

3. Space-efficient

Cons

1. Higher installation and maintenance costs

2. More maintenance required

3. Manual effort required to tilt the panels

Tracking Mounting Structures:

Tracking mounting structures are designed to follow the sun's movement throughout the day, adjusting the angle of the solar panels to maximize energy generation. These structures can be designed as single-axis or dual-axis systems, and they offer the highest energy generation potential of any mounting structure.

Single-axis tracking structures rotate the solar panels along a single axis, usually from east to west, while dual-axis tracking structures rotate the solar panels along both the east-west and north-south axes. Dual-axis tracking structures are the most efficient, but they are also the most complex and expensive.

Tracking structures use motors and sensors to follow the sun's movement, and they require a reliable power source to operate. They are typically installed on the ground rather than on rooftops since they require more space and can be heavy. However, some tracking structures can be designed for rooftop installations.

Pros

Maximum energy output

Better performance in shading conditions

Space-efficient

Cons

Higher installation and maintenance costs

More maintenance required

Ballasted Mounting Structures

Ballasted mounting structures rely on weight to keep the solar panels in place on the rooftop. Rather than using penetrations to attach the mounting structure to the roof, ballasted systems use concrete blocks or other heavy materials to secure the panels in place. Ballasted systems are typically used in flat-roof installations, where penetrations are not feasible or desirable. The weight of the ballast must be sufficient to withstand wind and other environmental forces while ensuring that the panels remain securely in place.

Pros

1. No penetration required

2. Easy installation

3. Space-efficient

4. Minimal maintenance

Cons

1. Limited wind resistance

2. Limited adjustability

3. Increases dead weight on roof

Integrated Mounting Structures

Integrated mounting structures are a type of solar PV mounting structure that are designed to be integrated into the building's structure, rather than added as a separate component. These structures can include solar panels that also serve as the building's roof or solar panels that are integrated into the building's face. Integrated mounting structures offer several advantages, including their ability to provide both solar energy generation and building functionality in one system. They also have a more aesthetically pleasing appearance since they can be designed to blend seamlessly into the building's architecture.

Pros

1. Aesthetically pleasing

2. Durable

3. Easy installation

4. Space-efficient

Cons

1. Limited adjustability

2. Limited compatibility

3. Higher cost

4. Retrofitting can be challenging

Flush Mounted Structures

Flush-mounted structures are installed directly onto the roof surface, allowing solar panels to be installed at a low profile. These systems are typically used for flat roofs, where it is difficult to use other mounting systems. Flush-mounted structures are cost-effective and require low maintenance. However, they may not be suitable for all roof types and may not provide optimal energy production compared to other mounting systems.

Pros

1. Cost-effective

2. Low maintenance

3. Aesthetically pleasing

4. Suitable for flat roofs

5. Ideal for reducing the dead load on your roof,

6. Suitable for high wind areas,

Cons

1. Limited adjustability

2. Limited compatibility

3. Reduced energy production

4. Potential for roof damage

East-west mounting structures

East-west mounting structures are designed to maximize energy production during the morning and evening hours when the sun is low on the horizon. The solar panels are installed in rows running east to west, instead of the typical south-facing orientation. Half of the panels face east and half towards the west. These systems can increase energy output by up to 15% compared to south-facing systems. However, they may require more space and may not be suitable for all roof types.

Pros

1. They reduce wind loads on the panels

2. More space efficient as space between panels is reduced

3. Intra-row shading is low

4. A little more energy in the mornings and evenings when the sun is at a lower level.

Cons

1. Maintenance is difficult as the space between panels is less.

2. More expensive than fixed tilt

High-rise or elevated structures

High-rise or elevated structures are used when there is limited space on the roof for solar panels or when the roof is not suitable for mounting. These structures can be installed on poles or pillars to elevate the solar panels above the roof surface. Elevated structures can provide optimal sun exposure and can be customized to fit specific site conditions. However, they may be more expensive and require more maintenance compared to other mounting systems.

Pros

1. Space efficient as space under the elevation can be used for other purposes like seating, gardening or drying clothes.

2. About 20% increase in solar output capacity

Cons

1. Suffers from wind loading and is not suitable for windy areas.

Conclusion

Choosing the right solar PV mounting structure is critical to the success of a solar rooftop system. The type of structure you choose will depend on a variety of factors, including your location, wind speed, roof type, and budget.