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Voltage optimisation

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Costs from £510+VAT, average bill reduction 12%, 4-7 year payback.

Key facts: Voltage Optimisation for homeowners

In line with CE and EU regulations, most of the UK’s electrical equipment is optimised to work at 220-230v. For historic reasons our electricity is supplied at an average of 242v but could be as high as 253v. It is a little known fact that the more voltage you apply to an appliance the more energy it consumes – costing you more and shortening the life of the device.

By matching your voltage supply to piece of equipment it is possible to make a substantial energy saving and prolong the life of appliances.  Most electronic equipment currently consumes more electricity than it needs to….

  • Typically reduces your electricity consumption by 10-12%.
  • Expected payback time 4-7 years.
  • Works well with Solar PV, wind turbines and heat pumps – some solar PV systems are cutting out because of the high incoming voltage and the system owner doesn’t know about it….
  • Prolongs the life of your electronic equipment: AAA rated appliances are rated at 220V, rather than 240V. They won’t behave as AAA rated at 240V, but that may not be clear when you buy the appliance.
  • Typical savings by appliance:
  • fluorescent lights 20%;
  • hairdryer 19%;
  • vacuum cleaner 18%;
  • microwave 16%;
  • fridge/freezer 10%;
  • patio heater 15%;
  • washing machine 7%;
  • dishwasher 5%.

Typical savings break down for a 4 bedroom household

The house has an average incoming voltage of 242v, and an annual load (pre-voltage optimisation) of 6,000 kWh.  Overall the system saves 700kWh per annum, being just under 12% of annual usage.  At a cost of just over 14p per kWh, that's a reduction in the bill of £100 per annum.

  Load (W) Hours per year Input voltage Reduced Voltage Annual kWh load % Saving Annual kWh saving
Mains lighting 1000 1825 242 223 1825 18.1% 331
Hairdryer 2200 39 242 223 86 18.1% 16
Vacuum cleaner 600 75 242 223 45 18.1% 8
Microwave 800 36.5 242 223 29 15.8% 5
Fridge 100 8760 242 223 876 10.3% 91
Freezer 200 8760 242 223 1752 10.3% 181
Washing machine 700 156 242 223 109 7.3% 8
Dryer 3000 117 242 223 351 7.3% 25
Dishwasher 1100 365 242 223 651 5.4% 36
Other         270    
Total         6000   701


Why Eco-max?

We install the Eco-Max system for several reasons:

  • As always, engineering excellence is at the top of the list. Eco-max engineers installed the first voltage optimisation system for British Steel in 2002, and have been perfecting their technology ever since.
  • Next comes customer service – the system has a 10 year no quibble guarantee, backed by first class customer service. Customers range from individual homeowners all the way to the big supermarkets.
  • UK made in Sheffield using durable, quality components.
  • Three settings for maximum control, depending on incoming voltage and load profile.
  • Fitted in a morning – works instantly.
  • No maintenance.
  • 10 year manufacturer’s warranty, expected life 20-30 years.

How much does it cost?

A voltage optimiser typically has an installed cost in the order of £510+VAT, so £612 inc VAT.  Depending on the level of your voltage, you can expect to make a 10% saving on your electricity bill. So if you are spending £1500 a year, that's a saving of £150.  So the system will pay for itself in just over 4 years.  With a small bill of around £800 a year, the payback time will be more like 7.5 years.  The voltage optimiser is warranted for 10 years and will last 20-30 years.

All projects are managed in house and installed by our solar panel installers. 


Call us on 0118 951 4490 for more information or request a quote online.

Homeowner Voltage Optimisation - Spirit Energy

Areas We Cover

For servicing and EV charging, we work within a 20 mile radius of Reading, Berkshire:


For PV and battery installations, please see our service area map.

Call us on 0118 951 4490 to discuss your project, or send in your plans for a free quotation.

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