So we have a an opportunity to build a number of DER or distributed generation sites running biogas + future solar; these are grid tied to the local power network. One of the connection challenges I have found is the cost of protection relays and generation control for a conventional AC mains parallel - mechanically governed generator; also on a technical level the variability of the gas production can be an issue.
Now the scale of the system would determine which design might be preferred based on ROI capex etc, and buffering the gas production with undersizing of the engine can generally solve the gas production challenge, but based on a) the power point tracking and/or b) the regulated protections that naturally come with inverters such as volt-var response / anti-islanding, overcurrent/earthfault etc, I consider an inverter/generator combination might be a good solution and a more compact simpler system from an installation-connection perspective,
So I have some questions:
- Is there an off the shelf option for a grid tied inverter with a coupled generator running constantly in parallel to the mains?
- Is this solution an AC or DC coupled generator governed by or via the inverter?
- Does there need to be batteries i.e. the biogas generator - charging batteries - batteries discharging via an inverter to the grid?
Like to hear others thoughts as well,
Happy to provide more information if required,