Power Saver Plugs
- Plug-in energy saving devices will not reduce your household electricity bill
- These energy saving devices are a scam
- Independent tests have shown these devices have serious safety defects
With the recent increase in electricity prices, we are all looking at ways to reduce our energy bills. Power saver plugs claim to reduce your household electricity use by simply plugging the device into a socket. The description of how these devices operate is usually vague and they often use nonsense terms like ‘straightening the current’, or ‘cleaning the dirty voltage’. Sometimes they may also mention ‘balancing current’ and using capacitors. Like all good scams, there is a grain of truth behind this. The principle they are based on is Power Factor Correction. Power factor correction is a genuine method of reducing electricity bills for commercial and industrial consumers. Unfortunately, these scam devices will not make any savings on your household electricity bill.
Domestic Electricity Bills
Power factor correction will never reduce household electricity bills. Domestic customers are only ever charged for Real Power, measured in kW or kilowatts. The power factor of the load does not affect your electricity bill and using a power factor correction device will not make any difference to the amount of electricity you are charged for.
Commercial Electricity Bills
Commercial and industrial customers are charged differently for electricity use than domestic customers. Commercial electricity usage is based on Apparent Power, measured in kVA or kilo volt-amperes. Essentially this means that they are charged more if the equipment they use causes the current and voltage to become out of sync (out of phase). Industrial equipment that generates a magnetic field to operate, such as motors and transformers, causes the current to lag behind the voltage. By adding capacitors to the system, the current can be brought back in sync with the voltage. This is referred to Power Factor Correction and is done to reduce the amount of power they are charged for. Power factor correction requires the careful selection of capacitors to match the load on the system. This article by the IET gives a great technical explanation of Power Factor Correction.
Electrical Safety First, the electrical safety charity, commissioned a series of independent electrical safety and performance tests on a number of these energy saving devices. The investigation revealed serious safety hazards for all the products tested. You can download the full report from the Electrical Safety First website.