Once electricity has been produced from the power station how does it get into the nat. grid?

Question

What form does it take and how does it get to our sockets?

Answer 1

The voltage gets transformed up to as much as 400,000 volts this enables it to travel long distances through the thin cables on the pylons.

Then at the other end it reaches sub stations and gets transformed back down again to your house voltage of around 250 volts. Then it travels underground in thick cables to your house.

Answer 2

The AC (alternating current) is actually produced by the generators in the power station, as they move a magnet (rotate) through a coil to induce a current. Therefore the national grid is directly linked to the generators. As others have said the number of windings on the coils determines the voltage produced, this is initially very high to prevent losses over the cables. Once transformed to the local voltage by the sub station the current drawn by you appliance will be several times greater than the resulting current drawn by the national grid.

i.e.

voltage and current are inversely proportional, so if you reduce the voltage from 10,000 volts to 240 volts, the current your kettle draws on the national grid will decrease by the same ratio. If we transported electricity at 240 volts the current (no. of electrons) travelling through the national grid would be huge, and the cables would heat up and loose all the energy (as heat) before it got to you in a similar way to how an electric heater works.

Answer 3

After generation, typically 25,000Volts, the voltage is stepped up to 400,000Volts(supergrid voltage) this means the currents in the powerlines are kept as low as possible as higher currents mean more losses and consequently lower efficiency. Most towns, depending on size, have a number of substations, which can usually be interlinked, which is useful for maintenance purposes(transformers can be taken out of service with no loss of power to customers). The voltages from super grid would be stepped down a number of times before it arrives at your local substation. 400,000-144,000- 12,000 for example. From a typical 10,000V-12,000V intake at your local substation it will then be stepped down again to 415V-440V. This is where it gets a little bit more complicated...In your home you will have ONE Live conductor ONE neutral conductor and a protective earth conductor. The live conductor will have a voltage of typically 230V + or - 5%. The substation has three lives(phases) coming out of it. The voltage between any two of these phases is the 415-440V mentioned earlier. Between any of the phases and the neutral conductor will be the 230V you expect to use in the home. If you can imagine a three bladed windmill, the three phases are generally depicted in this fashion, the point where the three blades meet is known as the 'star point' this is where the neutral is connected to at the substation. So between the star point and the end of blade will be your 230V. The cables that run down your street will contain all three phases and a conductor for the neutral (the earthing arrangements can vary widely). For a supply to work best, the current drawn on each phase should as equal as possible (otherwise the star point can theoretically 'move'). To this end, each dwelling will be on different phases e.g. on one side of the street, houses 2,4,6 will have L1, L2 and L3 respectively. Houses 8,10 and12 the sequence would repeat.
Once the supply has arrived within your dwelling, the live conductor is connected to one side of a fuse typically 80-125Amps, depending on the size of the property. The Neutral is connected into a Terminal block. The live and neutral is then connected into one side of a meter(supply side). On the other side of the meter (load side) there are connections to a consumer unit. The consumer unit has a number of overcurrent protection devices, if it's quite old these may be fuses. More modern installations will have MCBs (miniature circuit breakers). These will cause the supply to be cut to the relevant circuit if current exceeds it's design current. This is to prevent damage to the cicuit conductors and equipment.
The circuit(s) that supply your socket(s) may be arranged in a number of ways. The most common way is to have a number of sockets (within a pre-defined floor space) in a 'ring' arrangement. This means that a live, a neutral and an earth protective conductor comes from the consumer unit to the first socket, then loops onto the next socket and so on until the last socket. From the last socket a live, a neutral and earth protective conductor goes back to the consumer unit and is connected to the original live, neutral and earth, creating a 'ring main'. What this does, in effect, is double the size of the conductors involved.
The current carrying capacity of any cable is directly related to it's cross sectional area (csa). The Institution of electrical engineers stipulate minimum cable sizes and other criteria of all electrical installations.
Hope this helps, and please remember voltages mentioned above are for the uk and most of europe. If you are elswhere in the world the priciples will be the same but voltages might vary.

Answer 4

Generated at hi voltage probably 10,000volts AC you can only transform AC. This type of current can be imagined by swapping the ends of a battery over quickly, hence Alternating Current. It is then transformed up to say 66,000 volts and then possibly again to the grid at 128,000 volts. This is then tapped onto to give 33,000volt lines, and then 11,000 volt lines and then to 230 / 400volt local lines.

Answer 5

its loaded on the back of a truck n transported to where its needed, of course.......
what you thought it was sent down massive conducting cables to a power distribution plant, n then switched to various cables that run underground, or overhead cables that pass between pylons, carrying thousands of kilo-watts to various homes throughout the country,
dont be so gullible!

Answer 6

It takes the form of ... electricity, AC or DC, depending on witch side of the pond your on.

Answer 7

Review info at the following link:

http://www.energetics.com/gridworks/grid.html