What Recommendations Exist for Grounding Wind and Solar Hybrid Systems?

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Shared Grounding Point Design A shared grounding point is used to connect both the solar and wind systems to a common grounding point, typically a grounding rod or plate. This point should be located as close as possible to the main service panel and should be sized according to the combined grounding requirements of both systems. A shared grounding point is usually designed to handle the maximum fault current of both systems, which can be estimated using the combined short-circuit current of each system. For example, if the solar system has a short-circuit current of 20kA and the wind system has a short-circuit current of 30kA, the shared grounding point should be sized to handle at least 50kA.
Isolated Grounding Points Isolated grounding points are used to connect each system to its own grounding point, typically a grounding rod or plate. These points should be located as close as possible to the system’s main electrical panel and should be sized according to the grounding requirements of each system. Isolated grounding points are typically used for system grounding and bonding, and should be sized to handle the maximum fault current of each system. For example, if the solar system has a short-circuit current of 20kA, the isolated grounding point for the solar system should be sized to handle at least 20kA.
Grounding System Sizing Grounding system sizing is critical to ensure safe operation of the wind and solar hybrid system. The sizing of the grounding system should be based on the combined grounding requirements of both systems and should take into account factors such as fault current, system voltage, and system configuration. A common guideline is to size the grounding system to handle at least 125% of the maximum fault current of the combined system. This ensures that the grounding system can safely handle fault currents and prevent electrical shock or other safety hazards.