Magic of Making - Electricity

Electricity. It cooks our food, lights up our lives, and can even bring us the very best in top quality entertainment. The huge furnace sends out a steady stream of the red hot liquid into a pair of heatproof shears. It's hard to imagine life without it. This poor chap has a very dangerous job. He has to keep all the moulds clean with an oily stick. The energy of our electricity often begins as heat, created in huge power stations here billowing steam from the cooling towers. Inside the power station, steam is being used in quite another way. When water is heated in a boiler, the steam it makes becomes pressurised, and that pressure gives it the power to push a piston. The piston works with a flywheel to produce a steady spin. In the generator, that spinning motion is used to make electricity. Voltage and current combine as power, and power lights the bulb. There are thousands of bulbs on this building, and why not, because this is a nuclear power station. The locals call it the cathedral. This place produces energy from the splitting of atoms, and the destruction of matter itself, all beneath a neatly tiled floor. The fuel comes in as long rods of uranium metal that are raised and lowered by the crane in the middle of the hall. Down below, the heat from the nuclear furnace is pumped out on gases, rushing furiously through these smart green pipes. This is the turbine hall, and it's a plumber's nightmare. The heat from the nuclear reaction has been used to boil water, producing superheated steam that drives the blades of turbines encased within great metal overcoats. And this is what the place is all about, the generator, producing a thousand million watts of electrical energy. To safely carry all that power around the country, we use the pylons and wires of the national grid. If we go back to our beautiful model, we can get an idea of what the turbines under all that metalwork actually look like. In the generator, the rotation turns magnets against coils of wire called stators. Now, when you drag a magnetic field over a wire, charged atomic particles known as electrons will move with the field, and the movement of electrons is electricity. The high voltages carried by pylons can leap through the air on sparks, so we use transformers to step the voltage down. This little boy knows never to play with plugs and sockets, because electricity can be deadly. He also knows that the power moving his motor began with movement in the generator. Magnificent wind turbines make a valuable and clean contribution to our electrical demands, but only while the wind blows. Oh dear. And this demonstrates why it is wise to generate from a variety of sources. Hidden among the Welsh mountains of Snowdonia is a power station that is driven by the falling waters of a man-made lake. Tumbling through the heart of Electric Mountain, the waters are emptied into Llyn Peris, the lake down below. The energy released by this great drop can quickly replace the output of a broken power station somewhere else on the grid. A control room alarm is sounding. Hello. Okay, no problem, it's coming up now. Word of our boy's train has come through. A massive 16 tonne counterweight helps a huge valve to swing open, and every second, one and a half million teacups of water come crashing down the pipes. Behind the red plates, the water is directed onto the rotating fins of turbine runners like this. How the world has changed since scientists first understood how to harness the power of the mighty electron. Nature has been making electricity since time began, inside planets and creatures like you and me, and them. I think we should thank them all every time we turn on a light. Don't you?