There are still a few regions that are fully vertically integrated and fully regulated with no market prices. However, much of the US is under a regional ISO that sets hourly day ahead prices and 5-minute nodal spot prices. Under an ISO the utility still handles distribution and often transmission, but generation decisions (like when should I turn on my plant and what should my output be) are handled by the ISOs optimization auction based off various inputs from the generator such as costs and constraints.
In theory, this ISO setup has saved untold millions of dollars (probably billions), by operating the grid regionally in a much more efficient manner than in the days of old. It is hard to tell though as you can't do a direct comparison very easily. The economists certainly like the price signals though, but there are numerous issues.
In theory, this ISO setup has saved untold millions of dollars (probably billions), by operating the grid regionally in a much more efficient manner than in the days of old. It is hard to tell though as you can't do a direct comparison very easily. The economists certainly like the price signals though, but there are numerous issues.