What is Rooftop Solar?
Rooftop solar, also called distributed solar, refers to small-scale solar power systems that have been installed on the roofs of homes, businesses or organisations to offset a portion or all of the electricity used at the site where they are installed. This also includes solar panels installed over parking areas or in yards, but it is more common to utilise rooftops.
Rooftop solar has benefits and challenges when compared to utility scale solar.
Benefits
Rooftop solar utilises existing space & reduces land development
Rooftop systems are smaller and less complex, so require less design and planning to install individually and connect to the grid
Solar requires ongoing maintenance and monitoring to ensure maximum system efficiency and high-quality performance. Not all owners maintain their rooftop solar adequately, trim back shading trees or monitor for system faults. If not maintained correctly, the stability and reliability of the energy provided is impacted. Rooftop solar is not officially regulated in the Cayman Islands and CUC has limited ability to ensure that rooftop solar is high-quality, reliable, and working properly.
What is Utility Scale Solar?
Utility-scale solar, also called solar farms, are large solar power plants which provide the power they generate directly into the electric grid, which is then sold to customers.
Our analysis has determined that approximately 700 acres of land are needed for utility-scale solar for Grand Cayman within the energy mix we have proposed in our Integrated Resource Plan. This amount of land is available to support this development without disturbing mangroves or highly diverse habitats.
Once completed, utility-scale solar production will result in the equivalent to a 94% CO2 reduction compared to current sources of generation.
Utility-scale solar planning is influenced by several factors including the grid characteristics and geographic location. Utility-scale solar requires extensive planning, but presents incredible opportunities to make the biggest progress to transition electricity generation to renewable energy sources.
As with rooftop solar, there are benefits and challenges to be considered when it comes to utility scale solar.
Benefits
Lower cost energy: Due to economies of scale, optimized design and other factors, the cost per kilowatt hour of utility-scale solar is significantly lower than rooftop solar.
Stable supply: Dedicated care and maintenance of the system lead to reduced downtime resulting from failed equipment or suboptimal efficiency
Land use: Land is required to facilitate utility-scale solar development. However, there are growing opportunities to integrate multiple uses with land used for solar farms
So which option is best for Grand Cayman?
Utility-scale solar? Or rooftop solar? The answer: Both!
The combined methodologies will best provide what the country needs. Thoughtful deployment of a mix of these types of solar installations will help move Grand Cayman toward a greener grid while providing customers with affordable electricity.