Helping homes and businesses save money and reduce their carbon footprint

VO4 is a voltage optimisation system designed specifically for single phase and smaller 3-phase premises.

Made in SheffieldEMSc


VO4 in the Domestic Sector

Voltage optimisation; the key to sustainable homes

  • Saves on average £150 per year
  • Typical reduction in CO2 emissions of 330lbs-500lbs
  • No change to electricity supplier needed

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VO4 in the Retail Sector

Voltage optimisation; Top of the shopping list

12 month independent study by MJ Energy Services

  • Annual energy reduction of 10%
  • Payback in less than one year!
  • Saving over 12 month trial: £985

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VO4 in the Hospitality Sector

Voltage optimisation; Catering for the industry

in to lunch

  • 11.1% saving in energy consumption
  • Simple installation, no change to supplier needed
  • Reduced carbon footprint

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VO4 in the Solar Sector

Combining Solar & Voltage optimisation saves £££’s

  • Increase lifespan of the inverter
  • Reduce cut out frequency
  • Reduce heat build up and consequent losses

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VO4 in the Office Sector

Voltage Optimisation; Powering Profitability

  • Delivers substantial energy and carbon savings
  • Average savings of 10%-12% in electricity consumption
  • Reduce electricity usage with no affect to business operations

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VO4 in the Health Care Sector

Voltage optimisation; Delivering healthy savings

  • Make savings which can then be invested in patient care
  • Extends life and reliability of critical equipment
  • Works on all circuits 24 / 7

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What is VO4HOME?


VO4 are a range of British designed single and three-phase voltage optimisation systems for use in homes and small businesses.

The premise behind VO4 is simple, there is a discrepancy between the voltage supplied to a building by the grid, and that needed by on-site equipment.

VO4 optimises the incoming voltage to the level required by on-site electrical equipment, which in turn reduces electrical consumption, cuts electricity bills and lessens the wear on appliances.

VO4 Product Range


Company Heritage


VO4 is fully designed and manufactured by EMSc (UK) Ltd, the company behind the Powerstar range of voltage optimisation systems.

VO4 has been granted a number of accreditation’s for the manufacturing processes, operational procedures, systems and supply chains used, including the prestigious Made in Sheffield Mark of  Excellence, an exclusive accreditation is awarded to Sheffield companies who uphold the cities standards of excellence.

Company Information


Image banner 540x280VO4 voltage optimisation systems save on average £150 a year* and reduce energy consumption by 12%. Typical customers to benefit from VO4 are sites using up to 300,000kWh per year.

These typically include residential, retail outlets, funeral parlours, hotels, restaurants, laundrettes, GP surgeries, cafes, health clubs, small industrial units, office facilities and garden centres.

A 10% savings guarantee on annual electricity consumption is offered with all single phase installations.

Savings Studies


Benefits image web banner (72dpi)2VO4 helps homes and businesses reduce carbon footprint and save money on electricity bills.

It is a fit and forget solution, which requires no change to lifestyle or business operation. The units operate on all circuits 24 hours a day, 7 days a week and no maintenance is required.

Installation is quick and simple with no change to electricity supplier needed. Savings are immediate with typical paybacks under 5 years.

Benefits of VO4



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Frederick University carry out testing of VO4 Voltage Optimisation

Frederick University in Cyprus has carried out independent tests on VO4 voltage optimisation. The tests were carried out on a […]