The entire power grid has to be phased in sync to function. This requires substations and equipment AT EVERY POWER PLANT to work. The peaks and valleys ALL have to match- 60 times a second for U.S. power- or there WILL be an explosion somewhere in the grid. More powerplants CREATES waste as there is more energy lost in the phasing process.
The phasing of generators is done at the generator itself by synchronizing the actual mechanical rotation of the generator, NOT by substations adjusting phase.
It does NOT cause losses.
The rotation speed and position (physical angle relative to the AC voltage) of the actual generator shaft is how it is controlled.
Bringing a generator online requires aligning it to the local grid (actually slightly leading) and then connecting it.
It WILL snap into alignment at that point. If it lags it appears as a load to the grid and gets ‘pulled’ into alignment.
The fact that all the 'generators' are actually alternators (the magnetic field rotates and the output is taken from the stator windings) has some not obvious effects on operation, but they are secondary.
To further complicate power generation, the wavelength of 60 Hz power is ~5000 km, or ~3106 miles.
Strange things start to happen when your physical network size is a fraction of a major wavelength.
At a 90 degree phase shift an open circuit at one end of a line appears at the driving end as a short circuit.
90 degrees at 60 Hz (1/4 of a wavelength) is ~777 miles.
Long distance lines see these problems and have to deal with them.
Capacitor banks are used in the grid to adjust phase since the grid looks VERY inductive.
They do have some losses but they are actually very small.
The capacitors also help attenuate voltage disturbances on the line induced by lightning and switching of loads.
On long 3 phase transmission lines the 3 feeds are actually rotated in their tower positions periodically to make the impedance more uniform across the 3 conductors.
The main function of substations is increase and decrease the available voltage using transformers. They also provide control and overload protection (both voltage and current).
High voltage and low current save on transmission losses (both resistive and inductive).
We swap the high voltage for lower currents.
Even simple things like operating switches at very high currents is very difficult.
The magnetic fields cause all sorts of strange things to open as you try to open a switch.
We can prevent arcing from high voltage a lot better than we can deal with high magnetic fields from large currents.
If you have ever seen a power line fault you may have seen the lines feeding the fault actually move around and jump.
This is caused by the huge short circuit currents generating large magnetic fields that interacting with the earth’s magnetic field.
Even the typical 120/240 V house service requires an interrupt rating of 10,000 amps to ensure a short circuit WILL open under load.
) won't allow any more hydro-electric plants and push hard against fossil fuels. By be frank, nuclear is about the ONLY viable choice.