Does the voltage of alternating currents from a power plant need to be boosted or increased before it can enter a home?

Answer 1

The AC (alternating current) voltage from the power plant must be dropped, or transformed, down to an acceptable level before it can enter a home.

Power plants generate incredible amounts of power (electricity and current = power), that is difficult to distribute because of such massively high power. The method to do so is to generate the power with the highest voltage possible, which lowers the current proportionally. Hydro lines consist of wire conductors, all conductors pass electricity imperfectly due to resistance. Resistance converts power into heat as the electricity travels from the power plant to its destination. To minimise this loss, high voltage/lower current power is sent along the lines at voltages in excess of 220,000 volts along huge towers seen marching across the land.

This unusably high voltage must be converted into something more reasonable, so it ends up at a switching station as an important part of the electrical grid, at which point it is transformed to a much lower voltage at high current. Once it is distributed to area neighbourhoods, this voltage is again transformed to a lower voltage and much higher current.

Here's where a balancing act comes in. With the various voltages from "line loss" and the many transformer stations, it can result in a wide range of voltages when it reaches a given neighbourhood. Once it gets there, a transformer is matched to this end voltage that will provide the typical voltage of 220 and 115 volts. For factories, malls and industrial locations, voltages such as 600v, 480v, 277v, 220v, 208v and 110v is available.

A long answer to a short question - hope it's helpful.

Peace!

Dave

Comment

The main reason that energy is distributed at high voltages is to prevent enormous voltage drops from occurring along the line; a secondary reason is to enable us to use realistically-sized conductors; the reduction of energy or line losses is a bonus rather than a reason.