1 – How could I model the grid interconnection between two
separate regions? I would like to allow limited import/export of electricity
between two regions that are connected only by one High Voltage Link. Additionally, I would like to simulate a scenario where this link does not exist in the base year and is built a few years into the modelling scenario.

2 – Is it possible to set emission constraints at the
national level and then let the optimization software calculate the optimum
emission reduction in the separate regions? So far I managed to set
region-level emission constraints but I would like to set a national limit and
let the regions free to “set” their own limit. How could I do it?