# Why is electricity transported in high voltage but not in current?

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This is done in order to minimize power losses in the power distribution network due to the resistance of the transmitting cables. It should be noted that for a given cable resistance, voltage drop, and thus power dissipated in the cable and not available to use, is directly related to the current flow through the conductor.

According to the Power Law: P = I2 × R, that is power (in this case, power lost) is equal to current squared times resistance. To deliver power, it takes amps and volts. If you raise the volts, you can reduce the amps and still get the same power. If you reduce the amps, you lower the losses. Did you notice the squared term in the formula? That means if you reduce the current to one-tenth of the original value, your losses go down to one one-hundredth of what they were.

This is a huge issue for the utilities. Every kW lost is one they cannot collect money for, yet they still have to pay for fuel to generate it, they have to size the generator bigger to supply it, and they have to size the transmission system to carry it. There are other good reasons too (see below), but minimizing line loss is the \$main\$ one. A few transmission systems have been designed at 1.2 million volts. The utilities would have billion-volt systems if they could figure out how to do it.

A major reason is that, to carry the same amount of power, if the transmission voltage is made higher, then, even though a thinner cable has a higher resistance for a given length, the cables can be made thinner and lighter in weight.

Use of a higher transmission voltage saves a tremendous amount of money in many ways. For example for the expensive material used for the cables (often a steel multi-strand core wound with an outer skin of copper, aluminum, or similar good conducting wires) and for the weight and costs of construction and erection of the towers that carry the cables across the countryside.

To carry 400 kV (= 400 kilovolts = 400 thousand Volts) the steel towers have to be taller and the porcelain insulators have to be longer than they would have to be for cables carrying lower voltages but the cost of making the towers taller and the insulators longer is far less than the cost of the extra weight of the much thicker cables that would be needed to carry the same power at a lower voltage. *** (See Note below for more explanation)

There are many other costs which have to be reckoned when deciding what voltage to use for long-distance power distribution. For example the high cost of the massive power transformers and big switching stations that have to be included in the power distribution network; the power that is lost from the cables - radiated to the surrounding air as heat - because of the electrical resistance of the materials from which the cables are made.

The above answer just gives a very simplified overview of the kinds of things a skilled power transmission engineer has to work with and calculate when designing a new power transmission network.

Transmission and quantum of electricity can be considered analogous to hydraulics. Reckon voltage as pressure, the longer the distances, the higher the pressure required to pump. That is why for long distance transmission high pressure (voltage here) is required, failing which, the power will not reach the destined end. It will dissipate on the way. Reckon current as quantity which will be drawn from the pipeline (cables here) at the pressure/voltage required.

*** Note:
If we use the Electric Power Equation we can get an idea of what the descriptions given in the answers above really mean:

P = V × I or, in words:

P (power) = potential difference V (voltage) times current I (amperage)

So, using simple mathematics we can say that:

I = P / V or, in words:

Current I (amperage) = P (power) divided by potential difference V (voltage)

Now, as an example, if a small town needs to have a supply of power W of say 1 MW (= 1 megawatt = 1 million watts) to be delivered over cables from a power generation station:

Calculation A:
If the voltage V used for transmission through the cables is 1000 Volts then the current I in the cables would have to be:

P / V = 1,000,000 / 1,000 = 1,000 amps

which would require a very thick and heavy, and therefore very expensive, cable and associated support towers.

Calculation B:
If the voltage V used for transmission through the cables is 400 kV (= 400 kilovolts = 400,000 volts) then the current I in the cables would have to be:

P / V = 1,000,000 / 400,000 = 2.5 amps

which can be carried safely in a very much thinner, lighter and less expensive cable and support tower.

Line supports are mainly two types:

1. poles
Poles are classified as wood poles, concrete poles and steel/aluminum poles.

2. towers
Towers are classified as self supporting towers and stayed/guyed towers.
Self supporting towers are in two types: wide base and narrow base.
Stayed towers are classified as portal type and V-type.
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# What is electric current voltage?

Answer . At the typical U.S. home, the voltage at the wall outlet is somewhere between 110 and 120 Volts AC. Most U.S. homes also have 220 Volts (which is actually somewhere between 220 and 240 VAC) available, but not wired to most rooms.

# Which is more dangerous high-current or high-voltage?

current is the killer not volts, you can have thousands of volts but with out flow (current) the danger is minimal, but if you have voltage its very easy to induce current so be careful and let a professional take care of it if you do not know what you are doing.

# Is it possible to have a high current with low voltage?

It absolutely is-- to an amazing degree....! You can build a thermocouple junction with the junction shorted by a loop of copper or silver perhaps as thick as your arm and perhaps a foot in diameter. When you heat the thermocouple junction with a Bunsen burner flame, the thermocouple produces perha ( Full Answer )

# What is high voltage direct current?

I reckon this is mostly found in a wire connected to the picture tube of your TV. A flashligh battery is 1.5 volts. The DC on your pic tube may be 25 thousands volts or more.. Also, the term HVDC is a method of utility power transmission where buried cables use very high voltage DC instead of the u ( Full Answer )

# Why are low voltage electrical cables earthed and high voltage cables not in an electrical system?

The answer is more obvious if you use slightly different terminology to ask it. You could re-phrase the question as: Why are the low-voltage wires in a building earthed , but high-voltage transmission lines not? Wiring in a building or home that a person may come in contact with is earthed ( Full Answer )

# Why in high voltage electricity cables the current is carried by aluminum but the cable has a core of steel?

The reason for this is that aluminum has much higher electric conductivity than steel, but otherwise its mechanical properties are much worse. Steel core actually carries a cable.

# What converts high voltage electricity into low voltage electricity?

A transformer, . By appropriate selection of the numbers of turns, a transformer thus allows an alternating voltage to be stepped up - by making NS more than NP - or stepped down, by making it less. Transformers are some of the most efficient electrical 'machines,with some large units able to t ( Full Answer )

# The damaging effects of electric shock result from the current that flows in the body.Why then do signs read Danger-High Voltage rather than Danger-High Current?

It is true that the magnitude of current flow through the body determines the effects that occur. The path taken through the body is also responsible for the final outcome. For example the extremities will survive with higher current flow than the heart.. There are a lot of factors that effect the ( Full Answer )

# What is the difference between electric current and voltage?

Think of water in a pipe. Voltage is the pressure driving the water along the pipe. Current is how fast you send it along, how many gallons per minute. Voltage is measured in volts, current is measured in amps. One amp means an electrical charge of 1 coulomb goes through every second. A coulomb is ( Full Answer )

# Which electrical component regulates current and voltage?

People have used a ballast for current regulation and you can use a breakdown diode for voltage regulation.

# What is the electric current voltage in Egypt?

220V single phase (domestic) 380V three phase (industrial) Answer The voltage in Egypt is 220 V @ 50 Hz, compatible with most of Western Europe, but not with the US and Canada (which also have different plugs).

# Current always travels from high voltage to low voltage?

No. Current flows from a high potential to a low potential . 'Voltage' means 'potential difference ', not 'potential'.

# Why is electricity transmitted at a high voltage?

To reduce power losses. Power = voltage x current. Higher voltage means less current. Power loss is proportional to the square of the current.

# Why is electrical power transmitted in high voltage and not high current?

For any given load, the higher the supply voltage, the lower the resulting load current. A lower load current results in an acceptable voltage drop along the line, that conductors with lower cross-sectional areas can be utilised, and line losses are minimised. So high voltages are essential for en ( Full Answer )

# Why electrical power is transmitted in high voltage not in high current?

The wire used to transmit the electricity has a specific resistanceper unit length. Since power is equivalent to I^2 * R, the powerloss in the wire becomes greater as the current increases, whichresults in less energy to sell. It's more economical to transmit power at very high voltagesbecause of t ( Full Answer )

# Can air conduct high voltage electricity?

\nMost certainly. This is called an "arc" and is essential in the operation of some types of lamps. It is also the phenomenon that makes lightning possible.

# Is electric current a form of voltage?

No, electric current is the rate at which electrons flow in a conductor. The voltage is what makes the electrons move. They have different units of measurement It's a bit confusing and a bit of a cheat really Electrons are measured in units called Coulombs. And one coulomb is the number of ele ( Full Answer )

# Is Welding set a high voltage or high current load?

The arc utilized for arc welding is low voltage high current discharge. The voltage required for maintaining an arc is less than for striking the arc. Voltage drops & current increases as the arc is developed. The voltage required to strike DC arc is about 50-55 V & for AC is 80-90 V.It is difficult ( Full Answer )

# Why is it cheaper to transfer electrical power at high voltage and low current?

In general, it is cheaper to transport power long distances at higher voltage levels. Do not take this as a rule as always being cheaper, otherwise you would have a 500kV line into your home. The resistance in the power company's lines is not zero. There is always going to be some loss in quality w ( Full Answer )

# Is it possible to have electrical voltage exist but no electric current exist?

Yes. For example, a car battery always has a voltage of 12V (unless it gets completely unloaded, of course), between its terminals. But a current will only flow if cables are connected.\n

# What are high voltage electric wires made of?

Primary utility wiring uses an ACSR cable, (Aluminium Conductor Steel Reinforced). The multiple strands of aluminum wires are wound around a center steel cable. The steel center is used to allow longer spans between poles or towers. Ordinary aluminum wire can not be long spanned because its weight w ( Full Answer )

# How you would use the water flow to demonstrate a high voltage of electric current?

Electricity and water are often compared to help explain how electricity works. Voltage is like the speed of water in a river, and electrical current is like the amount of water in the river. Resistance can be compared to the physical width of the river. Power is voltage times current, or the spee ( Full Answer )

# Why the current is low when the voltage is high?

In principle it is possible to have any combination of voltage and current that you want, provided that you have the generating capacity to create it, however, it is also true that in some circumstances you get lower current with higher voltage, because you started with a moderate current at moderat ( Full Answer )

# What voltage is Japans electrical current?

"The voltage in Japan is 100 Volt" (japan-guide.com, 2007) "The frequency of electric current is 50 Hertz in Eastern Japan (including Tokyo, Yokohama, Tohoku, Hokkaido) and 60 Hertz in Western Japan (including Nagoya, Osaka, Kyoto, Hiroshima, Shikoku, Kyushu)" (japan-guide.com, 2007)

# Why electricity is transmitted at high voltages?

Electricity is transmitted at high voltages to minimize power losses due to the resistance of the wire. Power = Voltage * current, and Voltage = current * resistance. The resistance of the wire does not change with voltage level, so to power losses will be less for the same amount of power as voltag ( Full Answer )

# What causes electric shock current or voltage?

A spark from a metal door-knob, or from another person, or from a toy Van de Graf generator ... a high-voltage , low-current discharge ... can cause a startling surprise, but little lasting harm. An appreciable current passing through parts of the body, however, can burn flesh, cause dra ( Full Answer )

# Why is electricity distributed at high voltages?

Because distribution losses are lower at high voltages than at low voltages. Answer The answer provided above describes an advantage, rather than the reason, for transmitting energy at high voltages. The primary reason is that, by using high voltages, the resulting lower currents make it p ( Full Answer )

# What happens to electric current as voltage gets larger?

The electric current also increases(provided resistance remains constant) , as current is directionally proportional to voltage. V=IR(ohm's law)

# Why must electricity transmission lines be run at high voltage and low current?

Assume that only 120 volts is transmitted from the power stations throughout the whole distribution network. Then for 10 megawatt [as used by a VERY SMALL town ] the current would be have to be very high so the cables would have to be very thick and heavy - and therefore very expensive to buy and to ( Full Answer )

# Why is electrical power transmitted at high voltage?

To move the energy through the lines to reach the farthest user, electricity leaves the power plant at 24,000 volts to a transformer area, there it is increased to 304,000 volts which is used to move the energy through out the service area and reduced back down to be accepted in your house or place ( Full Answer )

# Why do you transmit alternating current at high voltage?

Because you can transfer high power without the cost of large conductors that would be needed if you transferred high current.

# What happens to electric currents if voltage becomes larger?

If the resistance of the load is kept more-or-less constant, then the current also becomes larger. On the other hand, if the power of the load is kept more-or-less constant, then the current becomes smaller.

# Why you transmit electricity over high voltages?

For a given load, the higher the supply voltage, the lower the resulting load current. If we didn't transmit electrical energy at very high voltages, the resulting line current would . require impractically-large conductors in terms of their cross-sectional area and weight. . cause a huge voltag ( Full Answer )

# What is voltage and current in electric arc welding?

I layman's terms Current is flow like water in a stream. Voltage is force, drive, power that pushes the current. Amperage is volume or amount of flow. Better described as in water in a hose. The higher the pressure the more the Voltage. The bigger the hose the more the Amperage. Both have flow.

# Who is responsible voltage or current for electric shock?

since both of them are responsible but the value of voltage must be more than that of the current. you can take the example of welding transformer, due to high current and low voltage welding is performed without giving any shock to the welder. so, for electric shock voltage is the most responsibl ( Full Answer )

# Who is resposible voltage or current for electric shock?

It is impossible to separate the two. The voltage determines the magnitude of the current, and the current causes the damage. So, they are both responsible for electric shock.

# How electricity transported in high voltage but not in current?

If electricity is transmit at high current then this will requires heavy conductors,be it copper or aluminium. This will increase the cost of transmission. Also, the heating effects i.e the energy lost due to head will increase as well. Thus, it's never ideal to transmit electricity at high current. ( Full Answer )

# Why is it important to select a high voltage and low current during trnsmission of electricity?

For a given load, the higher the supply voltage, the lower the load current. By using higher transmission voltages, the resulting lower currents ensure (a) minimal voltage drops along the lines, (b) conductors of practical size, and (c) less line losses.

# Can high voltage electricity be at home?

NO. No device or equipment at home are high voltage type. Hence it isnot necessary to have HV at home. Answer Devices that require high voltages, such as CRT television,electrostatic loudspeakers, etc., have transformers that increasethe supply voltage to that voltage.

# Why in transformer voltage is high and current is low?

An ideal transformer (one with no losses, and not a bad approximation for the real thing) has an input power equal to its output power. In simple terms, since power is the product of voltage and current, then for a given value of power, as the voltage goes up, the corresponding current will go down. ( Full Answer )

# What device uses the voltage in an electrical current?

A voltage , or potential difference , is what causes current to flow through a circuit. So all devices (called 'loads') require a voltage applied to them.

# What are the dangers of high voltage currents?

Electricity can be dangerous. You could get a fatal shock. The shock could fry skin as well as damage nerves. The shock might paralyze you. You could end up in the hospital for days.

# How many volts in high voltage electricity?

The value of high voltage is based on level of a spark produced and the level of a shock given. The standard numerical range in the US is any voltage over 600 The value of high voltage is based on level of a spark produced and the level of a shock given. The standard numerical range in the US is ( Full Answer )

# How do voltage and resistance effect electric current?

Voltage is the measure of electric potential, measure in volts. Resistance, measured in ohms, determined the resistance to the flowof current through a material. Current is the density of the flow of electrons past a point at agiven time, and is measured in amperes (or amps). Ohm's Law best describ ( Full Answer )

# What is a high voltage electric field?

Two plates with a voltage between them have an electric field inthe space between them equal to the voltage divided by thedistance. A single sphere at a high voltage has an electric fieldround it that decreases with distance. High voltage components havea strong electric field round them, and this c ( Full Answer )

# Why can't we generate electricity at high voltage?

We can up to 250,000 volts. That is almost always high enough, although if we could go higher it would be better for simulating lightning.

# Does the national grid transmit at high voltage or a high current?

Both. That way a lot of power can be transmitted. The largest UKgrid circuits work at 400 kV and a line of pylons can transmit upto 6000 MVA.

# What are high voltage electrical equipments?

In general equipment that runs on any voltage higher than normaldomestic and business supplies like the 400 v 3-phase standard inEurope. Examples are 3.3 kV and upwards.

# Is lightning a high-voltage electric current?

Yes, the clouds become electrically charged and when there isexcessive charge there is a big spark. The charge produces an electric field in the space under it, andwhen the field is high enough the gas atoms in the air break down,electrons are stripped off them and there is a plasma whichconducts el ( Full Answer )

# Why is voltage required for an electric current?

Because current won't flow unless there is a potential difference(voltage) between the two parts of the circuit. It's the potentialthat excites the electrons allowing them to move.