In the US this isn't even true. The costs of grid upgrades are paid new capacity up front, which actually means there is a queue for grid connections twice the US total production, with no costs to ongoing customers.
Grid upgrade costs are frequently socialized onto existing customers, especially for larger upgrades. Your central premise that interconnect charges cover everything is false.
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In the US this isn't even true. The costs of grid upgrades are paid new capacity up front, which actually means there is a queue for grid connections twice the US total production, with no costs to ongoing customers.
Your post is largely false, and quite confused.
Grid upgrade costs are frequently socialized onto existing customers, especially for larger upgrades. Your central premise that interconnect charges cover everything is false.
It varies by jurisdiction in the US.