Investigate the implementation of hurdle rates

In transmission system modeling, hurdle rates are economic parameters used to simulate the costs or disincentives associated with transferring electricity between different control areas or regions. They essentially act as a "toll charge" or a minimum savings criteria that must be met for power to flow across an inter-regional interchange.

While I don't think that it makes sense to be added to AC transmission objects, they can represent actual costs associated with using transmission lines between different areas, such as wheeling charges or explicit inter-area transfer fees. This ensures that the economic dispatch considers these transaction costs.

A proposed approach would be to add these costs to AreaInterchange models.