Even when our power generation was state-owned, they still operated as a state owned enterprise model.
If the price of your product is going negative, you have well and truly saturated the market. Even if our generation was nationalised, no government is going to build something where you have to pay someone else to use the output.
Price is a very effective way to control demand though, it's a big part of the reason we have a spot price electricity market. Even when all out generators were state owned, they operated on a state owned enterprise model of operation.
yes that's just further explanation within the confines of our current economic system, where productivity and well being are outcomes only when they align with profit