Support of grid
Especially in rural areas the power distribution is sometimes weak and due to a high impedance of the grid (esp. on single wire earth return systems see: www.ruralpower.org), the voltage is sometimes too low.
In this case you can use special alternators which support the grid.
If much power is recommended, the system will run as an alternator and it takes additional power out of a big lead acid battery (eg 24V/2000Ah).
When there is low demand on energy - especially during the night - the system will run as a battery charger and in the morning you will have a fully charged battery.
The fraron alternators can provide you with power from 3 kW singlephase up to 45 kW 3-phase additional current with a feeding line of only 1 to 6 kW single phase (or 3-phase where available).
Extra Low Voltage consumers like radio, TV , light and some special 24V DC refrigerators can be operated directly on the 24V DC grid.
Then you have more power for your 3-phase consumers left.
On the other side, it is possible to use solar pv modules and/or small DC wind turbines to charge the battery. Then you do not need so much energy out of the AC grid or you can have power when the powerline is down.
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