National Grid.

The National Grid is a network of high voltage electricity supplies that covers the UK in the manner of a spider’s web. Each main power station is connected to the grid so that the supply can be protected in the event of a breakdown or cable failure at any location.
It is owned and maintained by National Grid.  Their job is to ensure that the supply meets demand on a minute to minute basis.

The highly visible power station and pylons network cover carry power in a high voltage form, from power station to points of delivery.  Once at the point of delivery substations, which are basically large transformers, step the power down to the 230 volts AC that we use in our homes and workplaces.

Because of the high voltages used, overhead cables are highly dangerous; people are constantly advised to keep away from them, especially when flying kites, a damp kite string can carry a lethal shock from the cable to earth, probably killing the person holding it.  They operate an emergency phone line for reporting incidents connected with the grid.   Should you see a cable break or a fault at a sub station keep well away and contact the 24-hour electricity Emergency Number 0800 40 40 90.

As well as supplying and transmitting power across the UK, The National Grid can exchange power between Ireland and Mainland Europe when demand requires.  Power is not stored in the system, thus making it important to have flexibility of supply