Ground mounted solar installations can potentially be more cost-effective compared to roof-mounted installations. There are a few factors that contribute to this:

1. Simplified installation: Ground mounted solar systems are typically easier to install as they don't require intricate measures for roof attachment or potential structural modifications.

2. Optimal orientation and tilt: Ground mounted systems can be designed to maximize solar exposure by adjusting the orientation and tilt angles, ensuring optimal sunlight capture throughout the day.

3. Reduced maintenance costs: Ground mounted systems are generally easier to access for maintenance and cleaning, reducing the associated costs.

4. Scalability: Ground installations offer more flexibility for expanding the solar array in the future, as there is usually more available space compared to a limited roof area.

However, it's important to consider site-specific factors such as land availability, shading, ground preparation requirements, and potential additional costs for wiring and trenching. The overall cost-effectiveness will depend on the specific circumstances of the project.