The National Grid - Electricity generation - OCR 21st Century - GCSE Physics (Single Science) Revision - OCR 21st Century - BBC Bitesize (2024)

FAQs

What is the National Grid in GCSE physics? ›

The National Grid connects power stations to homes, workplaces and public buildings all around the country. The electricity may be produced by a conventional power station turning a generator close generatorDevice that converts kinetic energy into electrical energy. or by another method.

Efficiency of the National Grid

The National Grid transfers electricity using a high potential difference and a low current. This is because the National Grid needs to transfer a very large amount of energy.

National Grid power sources

Electricity is generally generated and fed into the National grid in alternating current (AC), typically at 275 or 400 kilovolts (kV), via step-up transformers. In the UK our electricity comes from a range of sources and the exact mix varies on a daily basis.

To move power around the National Grid: before electrical power leaves a power station – it is transferred at high voltages by using 'step-up' transformers to increase the voltage to around 275,000 V. before electrical power enters homes and factories – the voltages are decreased by 'step-down' transformers to 230 V.

A level 4 is now considered as a low C grade and a 5 a high C grade, or low B grade. Level 6 is a solid B, 7 an A grade and a level 8 an A*.

GCSE physics specification at a glance:

The three main exam boards that examine GCSE physics are AQA, OCR and Edexcel. Each board has two papers with the option of taking the foundation level or the higher level exam.

National Grid Electricity Transmission is responsible for making sure electricity is transported safely and efficiently from where it's produced to where it's needed.

Our nation's electricity grid consists of four major components, each of which is detailed below. A variety of facilities generate electricity, including coal- and natural gas-burning power plants, hydroelectric dams, nuclear power plants, wind turbines, and solar panels.

Some electrical energy is dissipated by network components and equipment such as transformers or conductors as a result of being connected to the network and being energised. Even if no power is delivered to customers, the system has losses just because it is electrically energised.

The United States and Canada use a supply voltage of 120 volts ± 6%.

Why DC is not used in home? ›

DC current is not used in homes because of the following reasons: First of all, DC is difficult to generate because primarily it is generated by batteries and electrochemical of photovoltaic cells. Power loss during transmission is more in direct current as compared to alternating current.

The mains supply in the UK is an alternating current (ac) voltage at a frequency of 50 hertz (Hz) and a voltage of 230 volts (V). The power input for households is ac as the National Grid can only use ac input. This means that the direction of the current and voltage changes 100 times per second.

1 Ownership and Corporate Structure

National Grid plc's top ten shareholders range from global asset management firms BlackRock and Vanguard to public pension funds, notably those of Norway and the Abu Dhabi Investment Authority. As of 2022, BlackRock held close to 9% of total shares.

That power enters your home at about 240 volts. This 240 volts is split at the main circuit breaker panel into two 120 volt halves, called phases. The 120 volt level is commonly referred to as 110, 115, 120, or 125 volts and is used for lighting and ordinary outlets.

It is the UK's largest electricity distribution network and serves nearly 8 million customers in the East and West Midlands, South West and Wales, delivering essential power to millions of homes and businesses across its regions.

We own the national electricity transmission system in England and Wales. The system consists of approximately 4,500 miles of overhead line, over 900 miles of underground cable and over 300 substations.

grid, in an electron tube, an electrode that has openings for controlling the flow of electrons or ions through it. Unmodified, the term applies to a control grid that is ordinarily placed between the cathode and the anode (or plate) of an electron tube to vary the flow of current.

Pylons and Cables

Electricity is transmitted across the country via overhead cables on pylons. These pylons are part of the National Grid, carrying a high voltage of up to 400,000 volts.