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Dirty Electricity

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What is Dirty Electricity?

Dirty electricity (DE), also known as dirty mains, dirty power, or electrical pollution, is a term that describes the problem of electromagnetic noise being on the mains wiring of a house, when it isn't supposed to be. Basically, your electrical supply is supposed to have just a 50 Hz sine wave on it, but this is rarely the case. There are almost always significant 2nd and 3rd harmonics (100 and 150 Hz in Europe, 120 and 180 Hz in USA), but these are not thought to be any more harmful than the pure sine wave.

DE occupies a part of the spectrum in-between the power frequency fields created by powerlines and substations, and the microwaves produced by mobile phone masts and other modern wireless devices.

DE consists of high frequency "electrical noise" of 1000 Hz (1 kHz) and upwards that has become superimposed on your wires. It includes transient spikes from inductive loads like motors being switched on and off. Most of the published work on this uses the Stetzer Microsurge meter which measures noise between about 2 kHz and 120 kHz

dLAN network adapters also put RF signals on your mains wiring and it is good to switch them off at night. The levels are vanishingly tiny when compared with wLAN / WiFi signals, however they may affect electrosensitive people. Please note: dLANs use frequencies above 150 kHz that extend up to several MHz and are not detected by the Dirty Electricity meter.

Dirty Electricity can travel into your house on the local electricity supply, or it can be generated by devices in your home. In the UK, the incoming supply is normally quite clean, so the majority of DE is generated by internal devices, though large blocks of flats and similar multi-occupancy living spaces can have a lot of shared DE sources. Bad electrical connections in the external supply lines to your home, or arcing on high-voltage feeder lines, can bring DE into your home along with the electricity supply. If you have high readings when everything in the house is switched off, then you need the DE filters to be placed as close as possible to the incoming mains supply - usually close to your fuse box / consumer unit.

Common large contributors to DE include dimmer switches, televisions, fluorescent light bulbs (including the relatively new CFLs, or energy efficient bulbs) and computers. Any device that has a "switched mode power supply" will naturally create a lot of noise, but it's hard to tell exactly which devices do have them and which ones don't. It's fairly new technology, so most modern, energy efficient, electronic devices now have them. Older, non-electronic devices such as lamps, ovens, or devices that run on motors, don't normally create much DE.

Many links have been made associating Dirty Electricity with a wide variety of negative health effects, including cancer, asthma, chronic fatigue syndrome, diabetes, ADD, autism and a number of neurological disorders.

We must note that whilst large amounts of DE noise is undoubtedly placed on the mains cable, the electromagnetic fields it causes the wiring in your house to emit are extremely low. However, despite our lack of understanding of the mechanisms, there is a significant body of anecdotal and scientific evidence to support the correlation between DE and various negative health effects.

Dirty Electricity Meters

The Dirty Electricity (DE) Meter is designed to help you assess the level of DE present within your home. When plugged in, it will measure the amount of high frequency noise (Dirty Electricity) in the frequency range 2 kHz to about 120 kHz on your mains circuit, and give you a reading.

The first step in assessing the DE within your house is to measure how much dirty electricity is currently in your house. We believe that a sensible, achievable goal is to try to keep readings well under 200. Plug the DE meter in and take note of the readings at several points around the house to give you a clear idea of what you currently have. If you have readings over 100, you may need to make some changes to get the reading lower. Some of the published material suggest readings below 50 GS units are required - this is difficult to achieve and we are not convinced of the extra benefit of doing so.

The next step is to work out how much of the dirty electricity is created by devices within your home, and how much is coming in directly from your electricity supplier. To do this, unplug all of the electrical and electronic devices in your house, so that they can't put dirty electricity onto your wiring (many modern devices use power even when they appear to be "off"). This includes things such as chargers, alarm clocks, etc - basically, if you can unplug it, then do so. Also switch off all lights. Once this is done, take measurements in the same places as before, and you're measuring just the electricity being supplied to you by the local suppliers. Any differences are due to devices in your own home.

If the differences are large, then some of the devices in your home are creating a lot of dirty electricity. Leave the DE meter plugged in, and try plugging in devices one-by-one, to work out how much each device is creating. Typically high devices include PCs, sounds systems, TFT/Plasma TVs, and other power-hungry electronic devices. Switch lights on and off. Compact fluorescents bulbs (CFLs) and low-voltage halogen downlighters (with hidden switched-mode voltage converters) can be significant sources of DE.

If you find that a large proportion of the DE is being produced by a handful of internal devices, then the best solution for these (e.g. computer equipment or TV and video equipment) is to put them on a proper Mains Filter Socket Strip (that contains proper filters, not just surge protectors), which prevents the DE from spreading onto the house wiring, confining it to a very small area. For devices creating a lot of DE, one of these will often be much more effective than a number of Electropulse filters, especially if you can group many of the high-DE producing devices onto a few filtered mains socket strips.

For any background DE which is coming in from the electricity provider, an Electropulse filter is probably more effective. This should be fitted as close as possible to your electricity meter or consumer unit (fuse box). For DE produced by the devices around your home, an Electropulse filter should be fitted as close as possible to the device producing the DE. You shouldn't need more than a few of these for the entire house, especially if you have used mains filter strips thoughtfully.

Background to Dirty Electricity measurements:

The original suggestion for a meter came from a Professor of Electrical Engineering in the USA called Martin Graham. He filed a US Patent that suggested possible circuitry for a suitable meter and the theory behind it. He produced a practical meter with Dave Stetzer who runs an electrical company in the USA. It is measured in what have become known as GS units. The term DE units is usually taken to have the same meaning.

The capacitance of a human to the live wires will usually be less than 800 picofarads and the current through the human will be proportionately lower. The current flow through the human will also depend on how the capacitance of the human to the wire is distributed over the person. This is important since it is the current flowing inside the body and where it is flowing that determines the effect it will have on the human.

The Dirty Electricity Meter measures the current in a 800 picofarad capacitor connected across the terminals of the outlet into which it is plugged. One GS unit is .02 micro amperes. A meter reading of 50 would indicate a current of one microampere.

The frequency band covered by the Dirty Electricity Meter is about 10 kHz to 100 kHz. If only one frequency sine wave is present, the meter reading is 0.24 times the rms voltage in millivolts times the frequency in kilohertz. In current terms, one GS unit is equal to .02 micro amperes. 900 GS units would be equal to 18 micro amperes.

You can also browse some of the published health related research from the Stetzer website.