Engineering Timelines - how to make electricity

So, just how does electricity get from huge power stations to our power points at home?

Here, electrical engineer John Biscoe explains
the electricity generation, transmission and distribution process.

But we wanted to know more. We wanted to know about carbon emissions and about what's needed to get electricity into our houses so we can make a little more sense of what we see in the media.

So, we asked him some questions.
You can read our interview with him.
See .... an electrical conversion >

This feature is sponsored by

POWER STATIONS IN THE UK

listed by fuel source

first coal fired

Battersea Power Station ... 1939

first nuclear

Calder Hall [ Magnox ] ... 1956
Chapelcross [ Magnox ] ... 1959

first hydroelectric schemes

Godalming Power Station, site of ... 1881
Bonnington [ run-of-the-river ] ... 1927
Stonebyres [ run-of-the-river ] ... 1927
Ffestiniog Pumped Storage ... 1963

first oil fired

Littlebrook B ... converted from coal 1970

gas fired

in widespread use from 1990

first wind powered

Delabole Wind Farm ... 1991

Supplying electricity

by John Biscoe, Director, GDM — building services and environmental engineers

Illustrations : Paul Weston

You can eavesdrop on the conversation between the electrical engineer John Biscoe and engineering timelines that we used to make this page. We aked him about the ins and outs of electricity supply and whether we have any choices .... an electrical conversion >

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FUEL
• In the UK, six different energy sources are used as primary fuel for power generation.
• Each has pros and cons.
• Environmental impact is calculated by adding together DIRECT and EMBODIED energy costs — embodied energy is the energy it takes to extract and transport the fuel.
more on fuel >

GENERATION
• The fuel is used to heat water, which drives the motion of huge turbines. The ever-moving turbines produce the electricity.
• It is produced at a value of 25kV (25,000 volts).
• The newly-generated current is fed through a series of transformers that step the voltage up to 400kV — it's more efficient to distribute it at high rather than low voltage, since this minimizes energy losses.
• Electricity cannot be stored. It is transmitted as soon as it is produced. When consumer demand falls, power generation halts.
more on generation >

TRANSMISSION
• Electricity is transmitted across long distances via aluminium cables suspended on transmission towers (pylons).
• Overhead cables are more efficient than underground cables for transmitting at high voltages — underground cables must be insulated to prevent short circuiting.
• Transmission is at a higher voltage than generation or distribution, to maximize efficiency across the system.
more on transmission >

DISTRIBUTION
• The electricity is sent to bulk supply transformer stations, closer to end users.
• These transformers step the voltage down to 132kV or 110kV.
• At this voltage, it is distrubuted to individual or small groups of end users.
more on distribution >

CONSUMER
• In the UK, electricity is distributed to consumers at 230 volts (standard UK voltage).
• Transformers are used to step the voltage down from distrubution levels to consumer level.
• Energy losses increase with this drop in voltage, so larger cables used are used inside buildings to compensate.
more on consumer >