MVP Southgate would supply Duke Energy Carolinas and Enbridge with gas, supplying power plants and gas customers.

South Dakota regulators approved a 7% increase in NorthWestern Energy's natural gas rates. (Photo by Getty Images) State regulators approved a settlement Tuesday in Pierre reducing NorthWestern ...

like Piedmont Natural Gas, to adjust rates on an annual basis. The utility estimates the fuel cost and then works with state regulators to tweak that rate periodically during the year. The same ...

South Dakota regulators approved a 7% increase in NorthWestern Energy's natural gas rates. (Photo by Getty Images) State regulators approved a settlement Tuesday in Pierre reducing NorthWestern Energy ...