Google tie-up lets you check power use

Power users can now buy an innovative device that lets them see how much power they are consuming, either by checking a display in their home or by logging on to Google's website.

The battery-powered device, made by British company CurrentCost, clips on to the wire leading out of an electricity meter and measures power consumption in real-time by detecting changes in the wire's magnetic field.

That information is sent wirelessly to a display panel which can be up to 30 metres away in the home or business.

The panel can be attached to a personal computer so consumption data can be uploaded to Google, allowing customers to keep tabs on their electricity consumption from anywhere.

The battery in the monitoring device needs to be replaced about every seven years.

About a million of the CurrentCost devices have been sold in Britain, North America and Australia.

Ian Ballantyne, technical director of Melbourne company SmartNow, which is now distributing them in New Zealand, says customers can use the information the monitors collect to detect waste and instantly see the effect of turning on or off any particular piece of equipment.

"Without real-time information, trying to reduce a power bill is like trying to reduce a monthly grocery bill without knowing any of the prices." He expects the monitors will appeal most to consumers, but that businesses will make the biggest savings.

Electricity retailers are installing "smart meters" in hundreds of thousands of homes and businesses, but they only record usage in half-hourly intervals and retailers do not at the moment let consumers see the data they gather.

Energy Efficiency and Conservation Authority research manager Robert Tromop says there is nothing new about the monitoring devices themselves, which are generically called CT (current transformer) clamps. But it is only recently that versions have been made that are suitable for use by consumers and he doubts many people would know that there are such tools to help them understand their power consumption.

"It is not that long ago these were industrial or commercial devices that electricians would use. The tip if you want to buy one of these is to make sure that the screen can tell you what you want to know."

Mr Ballantyne says CurrentCost's devices are accurate to within 2 or 3 per cent when customers are consuming less than a kilowatt (kW) and to between 5 and 8 per cent when electricity usage is between 1kW and 10kW.

SmartNow is shipping the devices from Australia for A$139 (NZ$171), but is in the process of appointing a New Zealand representative.

SmartNow recommends they be installed by an electrician, as clipping them on involves "operating in and around the electricity supply". Mr Tromop says that is prudent advice.

British utility company EON is providing the electricity monitors free-of-charge to customers as part of a conservation programme.

Google's not-for-profit arm Google.org, developed the Google PowerMeter software that is used to show electricity usage online. It is designed to an open standard, so it can display information from compatible devices made by other makers.

In August, CurrentCost will introduce a new panel display that can be plugged straight into an internet router, so customers can remotely monitor their power usage without having to leave their PC on.

- © Fairfax NZ News