why generation and transmission of power in UK can only be achieved using A.C supplies?

Answer 1

Due to Joule heating, large amounts of electrical energy must be transmitted at high voltage and low current. It's quite easy to perform this transformation with AC current but rather difficult to do so with DC - thus AC is pretty much the world standard for electrical power distribution.

Answer 2

First responder is correct. Actually, it is possible to transmit power via DC, and there are some transmission lines in the US that do so. Corona losses from the power line increase rapidly as the voltage is raised, and the peak voltage on an AC line is 40% higher than the useful voltage, so if you want to move a lot of power a long distance, it can be economical to convert it to DC for transmission, and back to AC at the far end. But the conversion equipment is costly, so it would not be used for lines in the UK -- they just aren't long enough to make it pay.

Answer 3

Mr. Edison and Mr. Tesla had this out over a century ago. A.C. wins because it is orders of magnitude more efficient for transmission. D.C. is possible, if you don't mind paying about a hundred times what you do now.

Answer 4

Unlike DC, AC electricity can be converted by transformers from low voltage, high current to high voltage, low current. (Power is the same as Power = Volts x Amps).

Transmitting power at high voltage (low current) is efficient as the higher the current the more loss there is in the cable. So lower the current, lower the loss.

So electricity is transmitted overland in the UK at 275,000 volts (Supergrid) or about 110,000 volts (normal grid).

Transformers in substations reduce the grid voltage down to 230v for your house supply.

Answer 5

It can be achieved by dc, but would be VERY much less efficient, and a lot of energy would be wasted. It applies to all countries, not just the UK.