Why optimise your electricity supply?

The declared electricity supply in the United Kingdom is now, as a result of European Harmonisation, 230V with a tolerance of +10% to -6%. This means that effective voltage can be anywhere between 216V and 253V depending on local conditions. Most electrical equipment manufactured for Europe and the UK is rated at 220V and operates more efficiently at this level.

Operating electrical equipment at higher than optimum voltages leads to significantly higher energy consumption. Equipment like lighting and motors consume more power at higher voltages. “A 230V linear appliance used on a 240V supply will take 4.3% more current and will consume almost 9% more energy.”
(Electrician’s Guide 16th Edition BS7671)