Do you know in what way this is actually stated, in what regulation, what law, what directive, or so on?

I imagine that given how the rules are actually framed, there might be certain loopholes, like borrowing via the state, then having the state issue all the cash to the state-owned utility via a rights issue, and so on. I.E. keep all the debt with the sovereign and have the utility funded solely through equity.

Peak oil is not an energy crisis. It is a liquid fuel crisis.