Substation
[edit] Introduction
In electrical engineering, a substation is a facility housing equipment that switches, transforms or converts high voltage electricity from a generating station into lower voltages that are easier and safer to distribute to homes, shops, small businesses and other consumers. This is necessary as it would be uneconomical and possibly dangerous to connect consumers directly to the main distribution network – they use small amounts of electricity in relation to industry and commerce – so it is 'stepped down' to a suitable voltage (240V AC in the UK) for local distribution.
Substations may also transform low-voltage electricity into higher voltages where large amounts of electricity are required, e.g a neighbourhood with numerous multi-storey buildings.
Sub-stations vary in size according to the type and number of customers they serve – they are usually larger if they serve commercial and industrial units, and smaller for residential neighbourhoods.
The equipment is typically freestanding, unprotected from the weather and cordoned off with a wire fence. The public is explicitly forbidden from entering and is alerted by signs warning of possible death by electrocution. Some substations are very close to houses and others even on customers’ land.
[edit] Magnetic fields
The equipment inside a substation produces a magnetic field but this reduces rapidly with distance, and by the time it reaches the perimeter fence it approaching background levels (i.e very low levels measured in microteslas (µT) – an SI unit of magnetic flux density equal to 10−6 teslas). The electrical lines entering a substation, whether underground cables or overhead lines, produce the highest magnetic field around the substation.
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
The 5 elements of seiri, seiton, seiso, seiketsu and shitsuke.
Shading for housing, a design guide
A look back at embedding a new culture of shading.
The Architectural Technology Awards
The AT Awards 2025 are open for entries!
ECA Blueprint for Electrification
The 'mosaic of interconnected challenges' and how to deliver the UK’s Transition to Clean Power.
Grenfell Tower Principal Contractor Award notice
Tower repair and maintenance contractor announced as demolition contractor.
Passivhaus social homes benefit from heat pump service
Sixteen new homes designed and built to achieve Passivhaus constructed in Dumfries & Galloway.
CABE Publishes Results of 2025 Building Control Survey
Concern over lack of understanding of how roles have changed since the introduction of the BSA 2022.
British Architectural Sculpture 1851-1951
A rich heritage of decorative and figurative sculpture. Book review.
A programme to tackle the lack of diversity.
Independent Building Control review panel
Five members of the newly established, Grenfell Tower Inquiry recommended, panel appointed.
Welsh Recharging Electrical Skills Charter progresses
ECA progressing on the ‘asks’ of the Recharging Electrical Skills Charter at the Senedd in Wales.
A brief history from 1890s to 2020s.
CIOB and CORBON combine forces
To elevate professional standards in Nigeria’s construction industry.
Amendment to the GB Energy Bill welcomed by ECA
Move prevents nationally-owned energy company from investing in solar panels produced by modern slavery.
Gregor Harvie argues that AI is state-sanctioned theft of IP.
Experimental AI housing target help for councils
Experimental AI could help councils meet housing targets by digitising records.
BSRIA Occupant Wellbeing survey BOW
Occupant satisfaction and wellbeing tool inc. physical environment, indoor facilities, functionality and accessibility.