The voltage supplied to your home or business needs to vary to ensure that the distribution network works effectively, offering the best supply to all users at all times. Across Europe the agreed statutory range for voltages is based on 230V +/-10% (207V to 253V). In the UK our voltages have historically been higher and whilst actual levels will vary during the day they typically average at around 245V.
The majority of appliances operate more efficiently at lower voltage (but still within the European statutory range). Voltage Optimisation is the control of voltage supplied to appliances to a set level (usually 220V). Presented below are example energy savings achieved in VPhase testing and based upon 245V to 220V voltage reduction.*
Appliances with motors and pumps
- 'A' rated freezer = 17% energy saving
- 'A' rated refrigerator = 16% energy saving
- 3 speed central heating pump = 15% to 18% energy saving
Lighting
- CFL lighting = 11% energy saving
- Incandescent bulb = 15% energy saving
- Low voltage halogen spot lights = 15% energy saving
It is important to note that there is some reduction in lighting levels as a result of lowering the voltage supplied, but typical consumer feedback reports that this is not an issue. Lighting is designed to work across a broad range of voltage supply according to the manufacturer’s specifications. As such, lowering the voltage will still be within the manufacturer’s guidelines and therefore the light output remains within an expected range of operation.
Consumer electronics
Results for consumer electronics vary widely, examples are given below:
- DAB radio = 5% energy saving
- DECT cordless phone base station = 30% energy saving
- ADSL modem and wireless router = 5% energy saving
- Personal Computer = 4% energy saving
- Hi-Fi = 13% energy saving
Electric heating
Closed loop (thermostatically controlled) heating will make no energy savings through the application of Voltage Optimisation. Reducing the voltage applied to an ohmic heating element will reduce the heat output from that element and the power drawn by that element however the element will remain on longer to achieve the same heating effect (and therefore consume the same amount of energy).
Whole house saving
There are many variables to determine the overall energy savings, however savings of between £50 and £135 a year off electricity bills have been demonstrated. If this were achieved in every house within the UK this would be the equivalent CO2 reduction of taking 2.3 million cars off the road every year.
Find out how much you could save by using our online savings calculator
*Based on back to back testing of a range of appliances by VPhase plc.
Actual results may vary depending on type of appliance, individual brand and incoming voltage.