> There are very few theories of business and/or economics where profits increase while costs are steady where prices don't increase.

There is a very specific and relevant one: The one in which supply is inelastic. In other words, the one in which it's hard to build new power plants.

When that happens, the cost of operating existing power plants hasn't changed, but demand goes up. In normal economics, demand going up causes the price (and therefore profit) to go up, which in turn attracts more suppliers that increase supply and mitigate the amount the price can increase.

If the supply can't go up then price does. That's econ 101 and it's happening just as it's expected to -- it's simply what happens if you make it hard to increase supply.