UK supply voltage typically arrives above the level much equipment is designed for. Reducing it at the point of entry can reduce consumption on some equipment and does nothing at all on the rest. Which of those describes your site is a measurement question, not a product question.
Verification
- Verified as at:
- Source:
- Omnium method; statutory UK supply voltage range
- Last reviewed by:
- Omnium
Figures in this sheet were current at the verification date above. Regulated charges reset each April. If you are relying on a figure, check the source or ask us.
Designed A4 fact sheet, ready to print or circulate.
The premise
The UK nominal supply voltage is 230V, with a statutory range of 216V to 253V. Delivered voltage commonly sits toward the upper part of that range, around 242V.
Equipment designed for 230V and supplied at 242V draws more than it needs to. On voltage-dependent loads, that excess is wasted.
Which loads benefit, and which do not
Benefit
Older lighting, uncontrolled motors and pumps, heating elements, older refrigeration.
Do not benefit
Modern LED lighting, IT equipment, inverter-driven motors and most variable speed drives.
A modern, well-specified site may have almost no voltage-dependent load left, in which case optimisation saves close to nothing. A site full of older plant may have a great deal.
On the numbers the industry quotes
Savings of roughly 5 to 19 per cent of electricity consumption are claimed across the industry. That range is an industry claim rather than an Omnium figure, and it applies only to the voltage-dependent portion of a site’s load, not to the whole bill.
Anyone quoting a flat percentage without having seen your equipment is selling rather than advising. The honest method is to measure the actual incoming voltage over time, assess the load mix, and estimate the saving on the voltage-dependent portion alone.
A credible assessment also identifies which supplies would benefit and which would not, so a unit is sized to those rather than blanketing the whole site.
The order it comes in
Voltage optimisation is worth looking at after the lighting has been dealt with, not before. Replacing older lighting with LED removes much of the voltage-dependent load, which shrinks the voltage optimisation case at the same time.
Doing them in the wrong order means paying for a unit sized against a load you are about to remove.
Related sheets
- LED lighting
Why LED is usually the most straightforward project on a site, and why the specification matters more than the headline.
- Power factor and reactive charges
A poor power factor means a site draws more current than the work requires, and pays for it through reactive charges and inflated capacity.
- The net zero roadmap
The order to decarbonise a building or portfolio in, and why measuring and reducing before generating and offsetting costs less.
Take this sheet into a meeting
Voltage optimisation is available as a designed A4 fact sheet, dated and set for printing or circulation.
If this sheet raises a question about your own sites, speak to us.