 The "Electrisave" (or "Centameter" as it was originally marketed in Australia) is an electricity metering device that uses wireless technology to bring the Energy Meter inside the house where the data can be easily monitored from the comfort of an armchair.
The device can show the electricity usage in KwH, monetary value or units of CO2. It also shows humidity and temperature (which is probably more relevant to those in warmer climates - like Australia, where air-conditioning usage is more common than it is in Northern Europe). The Brochure Claim is that the device can save you 25% off your electricity bills. Of course it does no such thing directly. The 25% claim comes from real research so it is in no way meant to be misleading, however its effect on people is to make them more conscious about their electricity usage. However, if you already are very conscious about your usage then this possibly has zero - or worse - negative effect upon your consumption. If you have lived a very wasteful life and walk around your house turning EVERYTHING on all the time then, sure, this will be an eye-opener. The research applies this kind of energy metering to homes and families who live a very average (read:- rich, western, northern or Australian) life. Yes, it should be very effective in raising your consciousness if you were previously completely careless about your usage. However, this doesn't mean we are cynical about the Electrisave. We just urge caution. It is designed to change your habits. If your habits had already changed then its effect is limited. Experiences shows that it provides interesting levels of information about household usage. For example, one sample house showed a continuous load of 0.4KwH at all times. This completely mystified the householder and lead to further lines of enquiry. So, it has its uses. Another good use is for householders with microgeneration systems. Although it cannot tell you the direction of electricity travel (in or out) you can generally guess. For example, if you have a Photovoltaic array on the roof and the sun comes out watch the Electrisave. If the value goes up then it is showing the net Export value. It can also provide a crude indication of the power usage of devices in your home for which there is no other way of measuring their power requirement. An example are the lights, central heating system, house alarm, and so on.  There a couple of drawbacks though. There is a 'Send' Unit and a Receiver/Display Unit. The Send Unit clamps around a cable in your Meter Box. however, it isn't that easy to find out which cable this is and we are sure many buyers would be initially frustrated to find that it doesn't work because they have the wrong cable. It isn't clear that you cannot clamp it to a cable with Live, Negative and Earth Cables inside. It must only be the Live Cable from Meter to House Main Fuse Board. If you know what that is then this is a good start.
The system requires lots of AA Batteries. It also drains these batteries very fast. Obviously you should use rechargeables but experience shows these do not last very long either. This is doubly a problem because the 'Send' Unit is clamped around a cable in your Meter Box which is likely to be outside the house! Hence it isn't always convenient to replace the batteries. What is even worse is that the Battery Compartment on the Send Unit has to be unscrewed. Hence you need a screwdriver. This would probably drive the average householder crazy and many would simply stop using it in frustration. Batteries cost money. The Electrisave costs money. Running it costs money and it consumes energy. Unless it is really useful to you then the money might be better spent elsewhere. | 
